style(tui): frame recovery decisions

README.md

@@ -209,7 +209,13 @@ Use `nanobot gateway --background` for the same direct entry point without keepi
 nanobot agent
 ```
 
-This opens the native terminal client with the configured model and tools, using the launch directory as its workspace. Use `/sessions` to switch saved conversations, `/new-chat` to preserve this conversation and start another one, `/branch` to fork from a completed reply, `/context` to inspect the compacted summary and raw message suffix available to the agent, or `/diff` to review the latest turn's file changes. Type `@` to mention an installed app, configured MCP server, or saved session. While nanobot is working, `Enter` steers the current turn, `Tab` queues a visible follow-up for the next turn, and `Option+Up` on macOS (`Alt+Up` on Windows/Linux) returns the latest queued message for editing. Press `Shift+Enter` to add a newline; `Ctrl+J` is the universal fallback for terminals that cannot distinguish modified Enter keys. Use `PageUp` at the top to load earlier transcript pages. Each launch starts a new session; `--session` selects an existing WebSocket session, while `--workspace` overrides the launch directory. Use `--classic` to resume a session from another channel. The existing nanobot `/new` command keeps its original behavior: it resets the current chat. `nanobot agent` and `nanobot webui` share one on-demand local gateway: either command can start it, each launcher releases only its own client, and the last interactive launcher to exit stops it. Use `/detach` to close the TUI while keeping the gateway and any active agent turn running in the background; after the terminal is restored, nanobot prints the exact `nanobot gateway stop` command for that config and workspace. Use `nanobot gateway --background` to start persistently before opening a client. Type `exit` or press `Ctrl+C` when you are done; after the terminal is restored, nanobot prints a ready-to-run `nanobot agent --session ...` command that resumes the session. Use `nanobot agent --classic` for the legacy Python prompt.
+This opens the native terminal client with the launch directory as its workspace. It shares saved conversations and the local gateway with the WebUI.
+
+- Type `/` to discover commands, `/sessions` to switch conversations, or `@` to mention an app, MCP server, or saved session.
+- Press `Enter` to send or steer, `Tab` to queue a follow-up, and `Shift+Enter` to add a newline (`Ctrl+J` works in terminals that cannot distinguish modified Enter keys).
+- Use `/detach` to leave the current task running, or start with `nanobot gateway --background` when nanobot should stay online after all local clients exit.
+
+Each launch starts a new session by default. Use `--session` to resume one and `--workspace` to choose another workspace. See the [CLI reference](./docs/cli-reference.md#agent-cli) for session branching, diffs, history, shortcuts, gateway lifecycle, and compatibility options.
 
 For one request and an immediate exit, use:
 

nanobot/agent/loop.py

@@ -79,6 +79,15 @@ from nanobot.session.model_selection import (
     SESSION_MODEL_PRESET_METADATA_KEY,
     model_preset_from_metadata,
 )
+from nanobot.session.recovery import (
+    PENDING_FOLLOWUP_ID_KEY,
+    RECOVERY_INBOUND_METADATA_KEY,
+    RecoveryAdmission,
+    acknowledge_pending_followups,
+    record_pending_followup,
+    restore_pending_interruption,
+    restore_runtime_checkpoint,
+)
 from nanobot.session.summary import SessionSummary
 from nanobot.triggers.local_turns import LocalTriggerTurnCoordinator
 from nanobot.utils.cancellation import task_is_cancelling
@@ -291,12 +300,14 @@ class AgentLoop:
         restart_mode: str = "auto",
         local_trigger_store: LocalTriggerStore | None = None,
         idle_compact_check_interval_seconds: int = 0,
+        recovery_admission: RecoveryAdmission | None = None,
     ):
         from nanobot.config.schema import ToolsConfig
 
         _tc = tools_config or ToolsConfig()
         defaults = AgentDefaults()
         self.bus = bus
+        self._recovery_admission = recovery_admission
         if turn_delivery_factory is not None:
             if turn_delivery_factory.bus is not bus:
                 raise ValueError("turn delivery factory must use the agent message bus")
@@ -409,6 +420,7 @@ class AgentLoop:
         # When a session has an active task, new messages for that session
         # are routed here instead of creating a new task.
         self._pending_queues: dict[str, asyncio.Queue[InboundMessage]] = {}
+        self._preserve_inflight_turns_on_shutdown = False
         self._deferred_automation_turns: dict[str, list[InboundMessage]] = {}
         self._cron_turns = CronTurnCoordinator(
             publish_inbound=self.bus.publish_inbound,
@@ -726,6 +738,9 @@ class AgentLoop:
                 extra[RUNTIME_CONTEXT_HISTORY_META] = runtime_context_meta
             session.add_message("user", text, **extra)
             self._mark_pending_user_turn(session)
+            followup_id = msg.metadata.get(PENDING_FOLLOWUP_ID_KEY)
+            if isinstance(followup_id, str) and followup_id:
+                acknowledge_pending_followups(session, [followup_id])
             self.sessions.save(session)
             return True
         return False
@@ -1061,6 +1076,9 @@ class AgentLoop:
                         row["subagent_task_id"] = task_id
                     row[HIDDEN_HISTORY_META] = subagent_marker
                     row["injected_event"] = "subagent_result"
+                followup_id = metadata.get(PENDING_FOLLOWUP_ID_KEY)
+                if isinstance(followup_id, str) and followup_id:
+                    row[PENDING_FOLLOWUP_ID_KEY] = followup_id
                 return row
 
             items: list[dict[str, Any]] = []
@@ -1285,6 +1303,23 @@ class AgentLoop:
                         break
                 if deferred:
                     continue
+                routed_msg = msg
+                if effective_key != msg.session_key:
+                    routed_msg = dataclasses.replace(
+                        msg,
+                        session_key_override=effective_key,
+                    )
+                # A newer WebUI message must supersede an explicit recovery
+                # before it is injected into that recovery's pending queue.
+                # Without this admission point, a recovered turn could finish
+                # first and only then observe the user's newer request.
+                if (
+                    effective_key in self._pending_queues
+                    and msg.channel == "websocket"
+                    and self._recovery_admission is not None
+                    and not await self._recovery_admission.admit(routed_msg)
+                ):
+                    continue
                 # If this session already has an active pending queue (i.e. a task
                 # is processing this session), route the message there for mid-turn
                 # injection instead of creating a competing task.
@@ -1297,12 +1332,18 @@ class AgentLoop:
                             self.commands.dispatch,
                         )
                         continue
-                    pending_msg = msg
-                    if effective_key != msg.session_key:
+                    pending_msg = routed_msg
+                    session = self.sessions.get_or_create(effective_key)
+                    followup_id = record_pending_followup(session, pending_msg)
+                    if followup_id is not None:
                         pending_msg = dataclasses.replace(
-                            msg,
-                            session_key_override=effective_key,
+                            pending_msg,
+                            metadata={
+                                **pending_msg.metadata,
+                                PENDING_FOLLOWUP_ID_KEY: followup_id,
+                            },
                         )
+                        self.sessions.save(session)
                     try:
                         self._pending_queues[effective_key].put_nowait(pending_msg)
                     except asyncio.QueueFull:
@@ -1310,6 +1351,7 @@ class AgentLoop:
                             "Pending queue full for session {}, falling back to queued task",
                             effective_key,
                         )
+                        msg = pending_msg
                     else:
                         logger.info(
                             "Routed follow-up message to pending queue for session {}",
@@ -1319,17 +1361,45 @@ class AgentLoop:
                 # Compute the effective session key before dispatching
                 # This ensures /stop command can find tasks correctly when unified session is enabled
                 task = asyncio.create_task(self._dispatch(msg))
-                active_tasks = self._active_tasks.setdefault(effective_key, set())
+                active_tasks: set[asyncio.Task[Any]] = self._active_tasks.setdefault(
+                    effective_key,
+                    set(),
+                )
                 active_tasks.add(task)
                 task.add_done_callback(active_tasks.discard)
         finally:
             await self.aclose()
 
+    def preserve_inflight_turns_on_shutdown(self) -> None:
+        """Keep durable checkpoints when the owning gateway exits.
+
+        Normal cancellation intentionally materializes partial output so a
+        user-stopped turn leaves a readable conversation.  Gateway lifecycle
+        shutdown is different: RecoveryCoordinator needs the checkpoint intact
+        to safely offer the unfinished turn for explicit continuation later.
+        """
+        self._preserve_inflight_turns_on_shutdown = True
+
     async def _dispatch(self, msg: InboundMessage) -> None:
         """Process a message: per-session serial, cross-session concurrent."""
         session_key = self._effective_session_key(msg)
         if session_key != msg.session_key:
             msg = dataclasses.replace(msg, session_key_override=session_key)
+        recovery_task_registered = False
+        recovery_admission = self._recovery_admission
+        current_task: asyncio.Task[Any] | None = None
+        if recovery_admission is not None:
+            recovery_id = msg.metadata.get(RECOVERY_INBOUND_METADATA_KEY)
+            if isinstance(recovery_id, str) and recovery_id:
+                current_task = asyncio.current_task()
+                if current_task is not None:
+                    recovery_admission.register_recovery_task(session_key, current_task)
+                    recovery_task_registered = True
+            if not await recovery_admission.admit(msg):
+                logger.info("Skipped stale recovery for session {}", session_key)
+                if recovery_task_registered and current_task is not None:
+                    recovery_admission.unregister_recovery_task(session_key, current_task)
+                return
         lock = self._get_session_lock(session_key)
         gate = self._concurrency_gate or nullcontext()
 
@@ -1373,14 +1443,14 @@ class AgentLoop:
                             session_key,
                             exc_info=True,
                         )
-                    # Preserve partial context from the interrupted turn so
-                    # the user does not lose tool results and assistant
-                    # messages accumulated before /stop.  The checkpoint was
-                    # already persisted to session metadata by
-                    # _emit_checkpoint during tool execution; materializing
-                    # it into session history now makes it visible in the
-                    # next conversation turn.
-                    if session_key in self._discarding_sessions:
+                    # An explicit turn stop materializes partial context so
+                    # the next prompt can see completed tool results.  Gateway
+                    # shutdown keeps the durable checkpoint untouched instead,
+                    # allowing RecoveryCoordinator to offer Continue safely.
+                    if (
+                        session_key in self._discarding_sessions
+                        or self._preserve_inflight_turns_on_shutdown
+                    ):
                         raise
                     try:
                         key = self._effective_session_key(msg)
@@ -1437,6 +1507,12 @@ class AgentLoop:
                         await delivery.idle()
                     await self._publish_next_deferred_automation_turn(session_key)
         finally:
+            if (
+                recovery_task_registered
+                and current_task is not None
+                and recovery_admission is not None
+            ):
+                recovery_admission.unregister_recovery_task(session_key, current_task)
             if pending is None:
                 await delivery.idle()
                 await self._publish_next_deferred_automation_turn(session_key)
@@ -1738,7 +1814,10 @@ class AgentLoop:
 
         if self._restore_runtime_checkpoint(session):
             self.sessions.save(session)
-        if self._restore_pending_user_turn(session):
+        if (
+            RECOVERY_INBOUND_METADATA_KEY not in msg.metadata
+            and restore_pending_interruption(session)
+        ):
             self.sessions.save(session)
 
     async def _compact_session(self, ctx: TurnContext) -> None:
@@ -2093,8 +2172,21 @@ class AgentLoop:
             if m.get("role") == "tool" and m.get("tool_call_id")
         }
         last_assistant_idx: int | None = None
+        saved_followup_ids: set[str] = set()
         for m in messages[skip:]:
             entry = dict(m)
+            followup_id_value = cast(object, entry.pop(PENDING_FOLLOWUP_ID_KEY, None))
+            followup_ids = (
+                [followup_id_value]
+                if isinstance(followup_id_value, str)
+                else [
+                    followup_id
+                    for followup_id in cast(list[object], followup_id_value)
+                    if isinstance(followup_id, str)
+                ]
+                if isinstance(followup_id_value, list)
+                else []
+            )
             internal_meta = cast(object, entry.pop("_meta", None))
             runtime_context_meta = (
                 cast(dict[str, Any], internal_meta).get(
@@ -2147,6 +2239,8 @@ class AgentLoop:
                     entry[RUNTIME_CONTEXT_HISTORY_META] = runtime_context_meta
             entry.setdefault("timestamp", datetime.now().isoformat())
             session.messages.append(entry)
+            if role == "user":
+                saved_followup_ids.update(followup_id for followup_id in followup_ids if followup_id)
             if role == "assistant":
                 last_assistant_idx = len(session.messages) - 1
                 declared_tool_call_ids.update(
@@ -2161,6 +2255,8 @@ class AgentLoop:
                 )
         if turn_latency_ms is not None and last_assistant_idx is not None:
             session.messages[last_assistant_idx]["latency_ms"] = int(turn_latency_ms)
+        if saved_followup_ids:
+            acknowledge_pending_followups(session, saved_followup_ids)
         session.updated_at = datetime.now()
 
     def _persist_subagent_followup(self, session: Session, msg: InboundMessage) -> bool:
@@ -2195,7 +2291,7 @@ class AgentLoop:
     def _set_runtime_checkpoint(self, session: Session, payload: dict[str, Any]) -> None:
         """Persist the latest in-flight turn state into session metadata."""
         session.metadata[self._RUNTIME_CHECKPOINT_KEY] = payload
-        self.sessions.save(session)
+        self.sessions.save_runtime_checkpoint(session)
 
     def _mark_pending_user_turn(self, session: Session) -> None:
         session.metadata[self._PENDING_USER_TURN_KEY] = True
@@ -2207,136 +2303,9 @@ class AgentLoop:
         if self._RUNTIME_CHECKPOINT_KEY in session.metadata:
             session.metadata.pop(self._RUNTIME_CHECKPOINT_KEY, None)
 
-    @staticmethod
-    def _checkpoint_message_key(message: dict[str, Any]) -> tuple[Any, ...]:
-        return (
-            message.get("role"),
-            message.get("content"),
-            message.get("tool_call_id"),
-            message.get("name"),
-            message.get("tool_calls"),
-            message.get("reasoning_content"),
-            message.get("thinking_blocks"),
-        )
-
     def _restore_runtime_checkpoint(self, session: Session) -> bool:
         """Materialize an unfinished turn into session history before a new request."""
-        from datetime import datetime
-
-        checkpoint = cast(
-            object,
-            session.metadata.get(self._RUNTIME_CHECKPOINT_KEY),
-        )
-        if not isinstance(checkpoint, dict):
-            return False
-        checkpoint_data = cast(dict[str, Any], checkpoint)
-
-        assistant_message = cast(object, checkpoint_data.get("assistant_message"))
-        completed_tool_results = cast(
-            Iterable[object],
-            checkpoint_data.get("completed_tool_results") or [],
-        )
-        pending_tool_calls = cast(
-            Iterable[object],
-            checkpoint_data.get("pending_tool_calls") or [],
-        )
-
-        restored_messages: list[dict[str, Any]] = []
-        if isinstance(assistant_message, dict):
-            restored = dict(cast(dict[str, Any], assistant_message))
-            restored.setdefault("timestamp", datetime.now().isoformat())
-            restored_messages.append(restored)
-        for message in completed_tool_results:
-            if isinstance(message, dict):
-                restored = dict(cast(dict[str, Any], message))
-                restored.setdefault("timestamp", datetime.now().isoformat())
-                restored_messages.append(restored)
-        for tool_call in pending_tool_calls:
-            if not isinstance(tool_call, dict):
-                continue
-            tool_call_data = cast(dict[str, Any], tool_call)
-            tool_id = tool_call_data.get("id")
-            function_data = cast(
-                dict[str, Any],
-                tool_call_data.get("function") or {},
-            )
-            name = function_data.get("name") or "tool"
-            restored_messages.append(
-                {
-                    "role": "tool",
-                    "tool_call_id": tool_id,
-                    "name": name,
-                    "content": "Error: Task interrupted before this tool finished.",
-                    "timestamp": datetime.now().isoformat(),
-                }
-            )
-
-        overlap = 0
-        max_overlap = min(len(session.messages), len(restored_messages))
-        for size in range(max_overlap, 0, -1):
-            existing = session.messages[-size:]
-            restored = restored_messages[:size]
-            if all(
-                self._checkpoint_message_key(left) == self._checkpoint_message_key(right)
-                for left, right in zip(existing, restored)
-            ):
-                overlap = size
-                break
-        appended_messages = restored_messages[overlap:]
-        session.messages.extend(appended_messages)
-        assistant_message_data = (
-            cast(dict[str, Any], assistant_message)
-            if isinstance(assistant_message, dict)
-            else None
-        )
-        provider_state_is_synchronized = (
-            checkpoint_data.get(self._PROVIDER_STATE_CHECKPOINT_VERSION_KEY)
-            == self._PROVIDER_STATE_CHECKPOINT_VERSION
-        )
-        phase = checkpoint_data.get("phase")
-        exact_final_response = (
-            phase == "final_response"
-            and assistant_message_data is not None
-            and assistant_message_data.get("role") == "assistant"
-            and not bool(checkpoint_data.get("completed_tool_results"))
-            and not bool(checkpoint_data.get("pending_tool_calls"))
-        )
-        exact_completed_tools = (
-            phase == "tools_completed"
-            and assistant_message_data is not None
-            and assistant_message_data.get("role") == "assistant"
-            and not bool(checkpoint_data.get("pending_tool_calls"))
-        )
-        if not (
-            provider_state_is_synchronized
-            and (exact_final_response or exact_completed_tools)
-        ):
-            session.provider_state = None
-
-        self._clear_pending_user_turn(session)
-        self._clear_runtime_checkpoint(session)
-        return True
-
-    def _restore_pending_user_turn(self, session: Session) -> bool:
-        """Close a turn that only persisted the user message before crashing."""
-        from datetime import datetime
-
-        if not session.metadata.get(self._PENDING_USER_TURN_KEY):
-            return False
-
-        if session.messages and session.messages[-1].get("role") == "user":
-            session.messages.append(
-                {
-                    "role": "assistant",
-                    "content": "Error: Task interrupted before a response was generated.",
-                    "timestamp": datetime.now().isoformat(),
-                }
-            )
-            session.provider_state = None
-            session.updated_at = datetime.now()
-
-        self._clear_pending_user_turn(session)
-        return True
+        return restore_runtime_checkpoint(session)
 
     async def process_direct(
         self,

nanobot/agent/runner.py

@@ -37,6 +37,7 @@ from nanobot.runtime_context import (
     reattach_runtime_context,
 )
 from nanobot.session.history_visibility import is_hidden_history_message
+from nanobot.session.recovery import PENDING_FOLLOWUP_ID_KEY
 from nanobot.utils.helpers import (
     IncrementalThinkExtractor,
     build_assistant_message,
@@ -234,6 +235,23 @@ class AgentRunner:
                         merged.get("content"),
                         injection.get("content"),
                     )
+                followup_id = injection.get(PENDING_FOLLOWUP_ID_KEY)
+                if isinstance(followup_id, str) and followup_id:
+                    existing = cast(object, merged.get(PENDING_FOLLOWUP_ID_KEY))
+                    followup_ids = (
+                        [existing]
+                        if isinstance(existing, str)
+                        else [
+                            item
+                            for item in cast(list[object], existing)
+                            if isinstance(item, str)
+                        ]
+                        if isinstance(existing, list)
+                        else []
+                    )
+                    if followup_id not in followup_ids:
+                        followup_ids.append(followup_id)
+                    merged[PENDING_FOLLOWUP_ID_KEY] = followup_ids
                 messages[-1] = merged
                 continue
             messages.append(injection)

nanobot/bus/outbound_events.py

@@ -62,6 +62,15 @@ class TurnEndEvent(OutboundEvent):
     context_window_tokens: int | None = None
 
 
+@dataclass(frozen=True)
+class RecoveryStateEvent(OutboundEvent):
+    status: str
+    recovery_id: str
+    reason: str | None = None
+    attempts: int = 0
+    can_continue: bool | None = None
+
+
 @dataclass(frozen=True)
 class GoalStatusEvent(OutboundEvent):
     status: str

nanobot/channels/manager.py

@@ -104,6 +104,9 @@ class ChannelManager:
         webui_mcp_runtime_status: Callable[[], Mapping[str, str]] | None = None,
         webui_mcp_reload: Callable[[], Awaitable[dict[str, Any]]] | None = None,
         webui_skill_state_action: Callable[[set[str]], None] | None = None,
+        webui_recovery_action: (
+            Callable[[str, dict[str, Any]], Awaitable[dict[str, Any]]] | None
+        ) = None,
         config_path: Path | None = None,
     ):
         if config_path is None:
@@ -126,6 +129,7 @@ class ChannelManager:
         self._webui_mcp_runtime_status = webui_mcp_runtime_status
         self._webui_mcp_reload = webui_mcp_reload
         self._webui_skill_state_action = webui_skill_state_action
+        self._webui_recovery_action = webui_recovery_action
         self.channels: dict[str, BaseChannel] = {}
         self._channel_owners: dict[str, str] = {}
         self._channel_runtime_specs: dict[str, tuple[str, str]] = {}
@@ -197,6 +201,7 @@ class ChannelManager:
                 mcp_runtime_status=self._webui_mcp_runtime_status,
                 mcp_reload=self._webui_mcp_reload,
                 skill_state_action=self._webui_skill_state_action,
+                recovery_action=self._webui_recovery_action,
                 logger=logger,
             )
             kwargs["gateway"] = gateway
@@ -615,6 +620,12 @@ class ChannelManager:
         if target is None:
             logger.warning("Restart notice target channel is not enabled: {}", notice.channel)
             return
+        if notice.channel == "websocket":
+            # Reconnect and recovery are already represented by WebSocket
+            # protocol state. A generic restart-complete notice must not
+            # masquerade as a recovery transition and overwrite a real
+            # awaiting-user checkpoint in connected clients.
+            return
 
         while not target.is_running:
             remaining = deadline - loop.time()

nanobot/channels/websocket/runtime.py

@@ -32,6 +32,7 @@ from nanobot.bus.outbound_events import (
     GoalStateSyncEvent,
     GoalStatusEvent,
     ProgressEvent,
+    RecoveryStateEvent,
     RuntimeModelUpdatedEvent,
     SessionUpdatedEvent,
     TurnEndEvent,
@@ -55,6 +56,7 @@ from nanobot.security.workspace_access import (
 )
 from nanobot.session.goal_state import goal_state_ws_blob
 from nanobot.session.model_selection import model_preset_from_metadata
+from nanobot.session.recovery import recovery_state_from_metadata
 from nanobot.session.webui_turns import (
     clear_websocket_turn_if_current,
     clear_websocket_turns,
@@ -453,6 +455,9 @@ class WebSocketChannel(BaseChannel):
             self.logger.warning("ignoring invalid model preset metadata for chat_id={}", chat_id)
             fields["model_preset"] = None
         if isinstance(metadata, dict):
+            recovery_state = recovery_state_from_metadata(metadata)
+            if recovery_state is not None:
+                fields["recovery_state"] = recovery_state
             usage = metadata.get("_last_usage")
             if isinstance(usage, dict):
                 sanitized_usage: dict[str, int | float] = {}
@@ -1740,6 +1745,10 @@ class WebSocketChannel(BaseChannel):
                     provenance=event.provenance,
                 )
             return
+        if isinstance(event, RecoveryStateEvent):
+            if conns:
+                await self.send_recovery_state(msg.chat_id, event)
+            return
         if isinstance(event, GoalStateSyncEvent):
             if conns:
                 await self.send_goal_state(msg.chat_id, event.goal_state or {"active": False})
@@ -2057,6 +2066,27 @@ class WebSocketChannel(BaseChannel):
         for connection in conns:
             await self._safe_send_to(connection, raw, label=" turn_end ")
 
+    async def send_recovery_state(
+        self,
+        chat_id: str,
+        event: RecoveryStateEvent,
+    ) -> None:
+        """Publish one structured recovery transition without chat pollution."""
+        body: dict[str, Any] = {
+            "event": "recovery_state",
+            "chat_id": chat_id,
+            "status": event.status,
+            "recovery_id": event.recovery_id,
+            "attempts": event.attempts,
+        }
+        if event.reason:
+            body["reason"] = event.reason
+        if event.can_continue is not None:
+            body["can_continue"] = event.can_continue
+        raw = json.dumps(body, ensure_ascii=False)
+        for connection in list(self._subs.get(chat_id, ())):
+            await self._safe_send_to(connection, raw, label=" recovery_state ")
+
     async def send_goal_state(self, chat_id: str, blob: dict[str, Any]) -> None:
         """Push persisted goal-state snapshot for *chat_id* (multi-chat isolation)."""
         conns = list(self._subs.get(chat_id, ()))

nanobot/channels/websocket/tests/test_websocket_channel.py

@@ -27,6 +27,7 @@ from nanobot.bus.outbound_events import (
     GoalStateSyncEvent,
     GoalStatusEvent,
     ProgressEvent,
+    RecoveryStateEvent,
     RuntimeModelUpdatedEvent,
     SessionUpdatedEvent,
     TurnEndEvent,
@@ -2720,6 +2721,39 @@ async def test_send_turn_end_emits_turn_end_event() -> None:
     ]
 
 
+@pytest.mark.asyncio
+async def test_recovery_state_is_a_structured_event_not_assistant_text() -> None:
+    bus = MagicMock()
+    channel = WebSocketChannel(
+        {"enabled": True, "allowFrom": ["*"]},
+        bus,
+        gateway=_basic_handler(bus),
+    )
+    mock_ws = AsyncMock()
+    channel._attach(mock_ws, "chat-1")
+
+    await channel.send(OutboundMessage(
+        channel="websocket",
+        chat_id="chat-1",
+        content="",
+        event=RecoveryStateEvent(
+            status="awaiting_user",
+            recovery_id="recovery-1",
+            reason="tool_state_unknown",
+            attempts=1,
+        ),
+    ))
+
+    assert _sent_ws_payloads(mock_ws) == [{
+        "event": "recovery_state",
+        "chat_id": "chat-1",
+        "status": "awaiting_user",
+        "recovery_id": "recovery-1",
+        "reason": "tool_state_unknown",
+        "attempts": 1,
+    }]
+
+
 @pytest.mark.asyncio
 async def test_system_command_turn_end_only_refreshes_session_metadata() -> None:
     bus = MagicMock()

nanobot/channels/websocket/tests/test_websocket_http_routes.py

@@ -83,6 +83,7 @@ def _make_handler(
     channel_feature_action: Any | None = None,
     channel_runtime_status: Any | None = None,
     mcp_reload: Any | None = None,
+    recovery_action: Any | None = None,
 ) -> GatewayServices:
     config = WebSocketConfig.model_validate(cfg) if isinstance(cfg, dict) else cfg
     workspace = workspace_path or Path.cwd()
@@ -103,6 +104,7 @@ def _make_handler(
         channel_feature_action=channel_feature_action,
         channel_runtime_status=channel_runtime_status,
         mcp_reload=mcp_reload,
+        recovery_action=recovery_action,
     )
 
 
@@ -121,6 +123,7 @@ def _ch(
     channel_feature_action: Any | None = None,
     channel_runtime_status: Any | None = None,
     mcp_reload: Any | None = None,
+    recovery_action: Any | None = None,
     **extra: Any,
 ) -> WebSocketChannel:
     cfg: dict[str, Any] = {
@@ -145,6 +148,7 @@ def _ch(
         channel_feature_action=channel_feature_action,
         channel_runtime_status=channel_runtime_status,
         mcp_reload=mcp_reload,
+        recovery_action=recovery_action,
     )
     return InProcessHttpChannel(cfg, bus, gateway=gateway)
 
@@ -3242,6 +3246,28 @@ async def _webui_mutate(
     )
 
 
+@pytest.mark.asyncio
+async def test_recovery_mutation_uses_authenticated_websocket_action(bus: MagicMock) -> None:
+    recovery_action = AsyncMock(return_value={
+        "status": "resuming",
+        "recovery_id": "recovery-1",
+    })
+    channel = _ch(bus, recovery_action=recovery_action)
+
+    response = await _webui_mutate(
+        channel,
+        "recovery.continue",
+        {"chat_id": "chat-1", "recovery_id": "recovery-1"},
+    )
+
+    assert response.status_code == 200
+    assert response.json()["status"] == "resuming"
+    recovery_action.assert_awaited_once_with(
+        "continue",
+        {"chat_id": "chat-1", "recovery_id": "recovery-1"},
+    )
+
+
 @pytest.mark.asyncio
 async def test_workspace_folder_picker_is_local_authenticated_mutation(
     bus: MagicMock,

nanobot/cli/gateway_runtime.py

@@ -322,6 +322,7 @@ def _run_gateway(
     from nanobot.providers.fallback_provider import FallbackProvider
     from nanobot.providers.image_generation import image_gen_provider_configs
     from nanobot.session.manager import SessionManager
+    from nanobot.session.recovery import RecoveryCoordinator
     from nanobot.session.webui_turns import (
         WebuiTurnCoordinator,
         WebuiTurnRoutePolicy,
@@ -422,6 +423,12 @@ def _run_gateway(
     tools = ToolRegistry()
     mcp_provider = MCPProvider.from_config(config, tools)
 
+    recovery = RecoveryCoordinator(
+        sessions=session_manager,
+        bus=bus,
+        unified_session=config.agents.defaults.unified_session,
+    )
+
     # Create agent with cron service
     agent = AgentLoop.from_config(
         config, bus,
@@ -440,6 +447,7 @@ def _run_gateway(
         local_trigger_store=trigger_store,
         hook_factories=[create_file_edit_activity_hook],
         tool_registry=tools,
+        recovery_admission=recovery,
     )
     def _schedule_webui_background(awaitable: Awaitable[None]) -> None:
         agent.schedule_background(cast(Coroutine[Any, Any, None], awaitable))
@@ -448,6 +456,7 @@ def _run_gateway(
         bus=bus,
         sessions=session_manager,
         schedule_background=_schedule_webui_background,
+        recovery=recovery,
     )
     webui_turn_coordinator.subscribe(runtime_events)
     from nanobot.bus.events import OutboundMessage
@@ -683,6 +692,7 @@ def _run_gateway(
         webui_mcp_runtime_status=mcp_provider.runtime_status,
         webui_mcp_reload=mcp_provider.reload,
         webui_skill_state_action=_webui_skill_state_action,
+        webui_recovery_action=recovery.handle_action,
         config_path=Path(config_path),
     )
 
@@ -849,6 +859,7 @@ def _run_gateway(
         tasks: list[asyncio.Task[Any]] = []
         shutdown_task: asyncio.Task[Any] | None = None
         runtime_tasks: asyncio.Future[list[Any]] | None = None
+        startup_complete = False
         shutdown_event = asyncio.Event()
         cli_terminal._ensure_interactive_tty_mode()
         restore_shutdown_handlers = _install_gateway_shutdown_handlers(
@@ -861,6 +872,10 @@ def _run_gateway(
             await cron.start()
             # Re-read once on first admission to close the watcher subscription window.
             agent.runtime_resolver.invalidate()
+            # Recovery must finish before WebSocket and other channels begin
+            # accepting new input.  That makes a new user message reliably
+            # supersede an old recoverable turn instead of racing its queue.
+            await recovery.scan()
             async def _run_agent() -> None:
                 try:
                     await mcp_provider.connect()
@@ -915,6 +930,7 @@ def _run_gateway(
                     name="nanobot-webui-dev-server",
                 ))
             runtime_tasks = asyncio.gather(*tasks)
+            startup_complete = True
             shutdown_task = asyncio.create_task(
                 shutdown_event.wait(),
                 name="nanobot-gateway-shutdown",
@@ -936,6 +952,10 @@ def _run_gateway(
 
             console.print("\n[red]Error: Gateway crashed unexpectedly[/red]")
             console.print(traceback.format_exc())
+            if not startup_complete:
+                # Do not report a successful gateway command when startup
+                # failed before any runtime task or listener was created.
+                raise typer.Exit(1)
         finally:
             try:
                 if shutdown_task and not shutdown_task.done():
@@ -943,6 +963,10 @@ def _run_gateway(
                     with suppress(asyncio.CancelledError):
                         await shutdown_task
                 cron.stop()
+                # A gateway exit interrupts ownership of active turns; it is
+                # not the same as the user stopping a turn.  Keep checkpoints
+                # so the next gateway can offer an explicit Continue action.
+                agent.preserve_inflight_turns_on_shutdown()
                 agent.stop()
                 # Cancel runtime tasks first, then deterministically close
                 # exec/MCP resources while the event loop is still alive.

nanobot/session/manager.py

@@ -48,15 +48,21 @@ _SESSION_PREVIEW_MAX_CHARS = 120
 _SESSION_LIST_PREVIEW_MAX_RECORDS = 200
 _SESSION_LIST_PREVIEW_MAX_CHARS = 1_000_000
 _SESSION_DATA_ERRORS = (ValueError, TypeError, AttributeError, KeyError)
+_RUNTIME_CHECKPOINT_DATA_ERRORS = (OSError, *_SESSION_DATA_ERRORS)
 _PROVIDER_STATE_RECORD_TYPE = "provider_state"
 _PROVIDER_STATE_RECORD_PREFIX_RE = re.compile(
     r'^\s*\{\s*"_type"\s*:\s*"provider_state"\s*(?:,|\})'
 )
+_RUNTIME_CHECKPOINT_KEY = "runtime_checkpoint"
+_RUNTIME_CHECKPOINT_VERSION = 1
+_RUNTIME_CHECKPOINT_SUFFIX = ".checkpoint.json"
 _FORK_VOLATILE_METADATA_KEYS = {
     "goal_state",
     "pending_user_turn",
+    "pending_user_followups",
     "runtime_checkpoint",
     "session_handle",
+    "webui_recovery",
     "thread_goal",
     "title",
     "title_user_edited",
@@ -1001,6 +1007,9 @@ class JsonlSessionStore:
     def get_session_path(self, key: str) -> Path:
         return self.sessions_dir / f"{self.storage_key(key)}.jsonl"
 
+    def get_runtime_checkpoint_path(self, key: str) -> Path:
+        return self.sessions_dir / f"{self.storage_key(key)}{_RUNTIME_CHECKPOINT_SUFFIX}"
+
     def get_legacy_lossy_path(self, key: str) -> Path:
         return self.sessions_dir / f"{safe_filename(key.replace(':', '_'))}.jsonl"
 
@@ -1066,7 +1075,7 @@ class JsonlSessionStore:
                     else:
                         messages.append(data)
 
-            return Session(
+            session = Session(
                 key=key,
                 messages=messages,
                 created_at=created_at or datetime.now(),
@@ -1075,6 +1084,8 @@ class JsonlSessionStore:
                 last_consolidated=last_consolidated,
                 provider_state=provider_state,
             )
+            self._overlay_runtime_checkpoint_unlocked(session, path)
+            return session
         except _SESSION_DATA_ERRORS as e:
             logger.warning("Failed to load session {}: {}", key, e)
             repaired = self._repair_unlocked(key)
@@ -1159,7 +1170,7 @@ class JsonlSessionStore:
             if not messages and not metadata and provider_state is None:
                 return None
 
-            return Session(
+            session = Session(
                 key=key,
                 messages=messages,
                 created_at=created_at or datetime.now(),
@@ -1168,6 +1179,8 @@ class JsonlSessionStore:
                 last_consolidated=last_consolidated,
                 provider_state=provider_state,
             )
+            self._overlay_runtime_checkpoint_unlocked(session, path)
+            return session
         except _SESSION_DATA_ERRORS as e:
             logger.warning("Repair failed for session {}: {}", key, e)
             return None
@@ -1186,6 +1199,105 @@ class JsonlSessionStore:
         with self._session_files_lock:
             self._save_unlocked(session, fsync=fsync)
 
+    def save_runtime_checkpoint(self, session: Session) -> None:
+        """Atomically persist only the volatile in-flight turn state.
+
+        A checkpoint is written several times during a tool-heavy turn. Keeping it
+        beside the append history avoids copying the full transcript at each safe
+        recovery boundary.
+        """
+        with self._session_files_lock:
+            path = self.get_session_path(session.key)
+            if not path.exists():
+                # A user turn normally creates the session first. Internal callers
+                # may checkpoint a fresh session, so establish the durable base once.
+                self._save_unlocked(session)
+                return
+
+            checkpoint = session.metadata.get(_RUNTIME_CHECKPOINT_KEY)
+            if not isinstance(checkpoint, dict):
+                self.get_runtime_checkpoint_path(session.key).unlink(missing_ok=True)
+                return
+
+            payload: dict[str, Any] = {
+                "version": _RUNTIME_CHECKPOINT_VERSION,
+                "session_key": session.key,
+                "base_updated_at": session.updated_at.isoformat(),
+                "base_message_count": len(session.messages),
+                "checkpoint": checkpoint,
+                "provider_state": (
+                    session.provider_state.to_private_record()
+                    if session.provider_state is not None
+                    else None
+                ),
+            }
+            target = self.get_runtime_checkpoint_path(session.key)
+            tmp = target.with_name(f".{target.name}.{secrets.token_hex(8)}.tmp")
+            try:
+                with open(tmp, "x", encoding="utf-8") as handle:
+                    os.chmod(tmp, 0o600)
+                    json.dump(
+                        payload,
+                        handle,
+                        ensure_ascii=False,
+                        separators=(",", ":"),
+                    )
+                os.replace(tmp, target)
+            finally:
+                tmp.unlink(missing_ok=True)
+
+    def _overlay_runtime_checkpoint_unlocked(self, session: Session, main_path: Path) -> None:
+        checkpoint_path = self.get_runtime_checkpoint_path(session.key)
+        try:
+            checkpoint_stat = checkpoint_path.lstat()
+            if not stat.S_ISREG(checkpoint_stat.st_mode):
+                logger.warning(
+                    "Ignoring non-regular runtime checkpoint for session {}",
+                    session.key,
+                )
+                return
+            # A complete session save supersedes an older sidecar. This comparison
+            # closes the small crash window between replacing the JSONL and unlinking
+            # its previous checkpoint.
+            if main_path.stat().st_mtime_ns > checkpoint_stat.st_mtime_ns:
+                checkpoint_path.unlink(missing_ok=True)
+                return
+            raw = _json_object(json.loads(checkpoint_path.read_text(encoding="utf-8")))
+            if (
+                raw.get("version") != _RUNTIME_CHECKPOINT_VERSION
+                or raw.get("session_key") != session.key
+                or raw.get("base_updated_at") != session.updated_at.isoformat()
+                or raw.get("base_message_count") != len(session.messages)
+                or not isinstance(raw.get("checkpoint"), dict)
+            ):
+                checkpoint_path.unlink(missing_ok=True)
+                return
+            provider_record = raw.get("provider_state")
+            provider_state = (
+                None
+                if provider_record is None
+                else ProviderConversationState.from_private_record(provider_record)
+            )
+            if provider_record is not None and provider_state is None:
+                raise ValueError("invalid checkpoint provider state")
+            session.metadata[_RUNTIME_CHECKPOINT_KEY] = cast(
+                dict[str, Any], raw["checkpoint"]
+            )
+            session.provider_state = provider_state
+        except FileNotFoundError:
+            return
+        except _RUNTIME_CHECKPOINT_DATA_ERRORS as exc:
+            logger.warning(
+                "Ignoring invalid runtime checkpoint for session {}: {}",
+                session.key,
+                exc,
+            )
+            # Atomic writes mean a malformed target cannot become valid later.
+            # Remove it once so future loads do not repeatedly parse and log it.
+            with suppress(OSError):
+                if checkpoint_path.is_file() and not checkpoint_path.is_symlink():
+                    checkpoint_path.unlink()
+
     def _save_unlocked(self, session: Session, *, fsync: bool = False) -> None:
         path = self.get_session_path(session.key)
         tmp_path = path.with_name(f".{path.name}.{secrets.token_hex(8)}.tmp")
@@ -1215,6 +1327,10 @@ class JsonlSessionStore:
 
             os.replace(tmp_path, path)
 
+            # The full record now contains the authoritative checkpoint state (or
+            # its removal), so an older volatile overlay is no longer needed.
+            self.get_runtime_checkpoint_path(session.key).unlink(missing_ok=True)
+
             if fsync:
                 with suppress(PermissionError):
                     fd = os.open(str(path.parent), os.O_RDONLY)
@@ -1278,6 +1394,7 @@ class JsonlSessionStore:
     def _delete_unlocked(self, key: str) -> bool:
         paths = [
             self.get_session_path(key),
+            self.get_runtime_checkpoint_path(key),
             self.get_legacy_lossy_path(key),
             self.get_legacy_session_path(key),
         ]
@@ -1585,6 +1702,10 @@ class SessionManager:
         """Get the collision-resistant workspace path for a session."""
         return self._jsonl_store.get_session_path(key)
 
+    def _get_runtime_checkpoint_path(self, key: str) -> Path:
+        """Get the private in-flight checkpoint path for a session."""
+        return self._jsonl_store.get_runtime_checkpoint_path(key)
+
     def _get_legacy_lossy_path(self, key: str) -> Path:
         """Previous workspace session path using lossy ':' to '_' replacement."""
         return self._jsonl_store.get_legacy_lossy_path(key)
@@ -1653,6 +1774,18 @@ class SessionManager:
         self._store.save(session, fsync=fsync)
         self._remember(session)
 
+    def save_runtime_checkpoint(self, session: Session) -> None:
+        """Persist volatile recovery state without rewriting long history."""
+        if not session.policy.persist:
+            return
+        if self._store is self._jsonl_store:
+            self._jsonl_store.save_runtime_checkpoint(session)
+            self._remember(session)
+            return
+        # Third-party stores keep their existing all-or-nothing semantics until
+        # they opt into a dedicated checkpoint primitive.
+        self.save(session)
+
     def rename_model_preset(self, old_name: str, new_name: str) -> int:
         """Rename a session-scoped model preset across durable and live sessions."""
         if old_name == new_name:

nanobot/session/recovery.py

@@ -0,0 +1,939 @@
+"""Durable, side-effect-safe recovery for interrupted WebUI turns.
+
+The coordinator owns restart policy.  AgentLoop only exposes checkpoint
+materialization and an admission hook, so transport code never has to guess
+whether an interrupted tool call is safe to replay.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import dataclasses
+import json
+from collections.abc import Iterable, Mapping
+from datetime import datetime
+from typing import Any, Protocol, cast
+from uuid import uuid4
+
+from loguru import logger
+
+from nanobot.bus.events import InboundMessage
+from nanobot.bus.outbound_events import (
+    RecoveryStateEvent,
+    SessionUpdatedEvent,
+    outbound_message_for_event,
+)
+from nanobot.bus.queue import MessageBus
+from nanobot.session import turn_continuation
+from nanobot.session.keys import UNIFIED_SESSION_KEY, last_channel_from_metadata
+from nanobot.session.manager import Session, SessionManager
+from nanobot.webui.metadata import WEBUI_TURN_METADATA_KEY
+
+RUNTIME_CHECKPOINT_KEY = "runtime_checkpoint"
+PENDING_USER_TURN_KEY = "pending_user_turn"
+RECOVERY_METADATA_KEY = "webui_recovery"
+RECOVERY_INBOUND_METADATA_KEY = "_webui_recovery_id"
+PENDING_FOLLOWUPS_KEY = "pending_user_followups"
+PENDING_FOLLOWUP_ID_KEY = "_recovery_followup_id"
+PROVIDER_STATE_CHECKPOINT_VERSION_KEY = "provider_state_checkpoint_version"
+PROVIDER_STATE_CHECKPOINT_VERSION = "v1"
+
+_RECOVERY_STATUSES = frozenset({"resuming", "awaiting_user", "recovered", "failed"})
+_UNCERTAIN_TOOL_PHASES = frozenset({"awaiting_tools"})
+_KNOWN_CHECKPOINT_PHASES = frozenset(
+    {"final_response", "tools_completed", "awaiting_tools", "error"}
+)
+
+
+class RecoveryActionError(ValueError):
+    """A stale or malformed recovery action from an authenticated WebUI."""
+
+    def __init__(self, message: str, *, status: int = 400) -> None:
+        super().__init__(message)
+        self.status = status
+
+
+class RecoveryAdmission(Protocol):
+    """Narrow AgentLoop boundary for explicit recovery validation."""
+
+    async def admit(self, message: InboundMessage) -> bool: ...
+
+    def register_recovery_task(self, session_key: str, task: asyncio.Task[Any]) -> None: ...
+
+    def unregister_recovery_task(self, session_key: str, task: asyncio.Task[Any]) -> None: ...
+
+
+def record_pending_followup(session: Session, message: InboundMessage) -> str | None:
+    """Durably journal a WebUI follow-up before injecting it into a live turn."""
+    if message.channel != "websocket":
+        return None
+    try:
+        metadata_value: object = json.loads(json.dumps(message.metadata))
+    except (TypeError, ValueError):
+        logger.warning("Skipping non-serializable WebUI follow-up for recovery")
+        return None
+    if not isinstance(metadata_value, dict):
+        return None
+    metadata = cast(dict[str, Any], metadata_value)
+    existing_id = metadata.pop(PENDING_FOLLOWUP_ID_KEY, None)
+    followup_id = (
+        existing_id
+        if isinstance(existing_id, str) and existing_id
+        else uuid4().hex
+    )
+    records = _pending_followup_records(session)
+    if any(record.get("id") == followup_id for record in records):
+        return followup_id
+    records.append(
+        {
+            "id": followup_id,
+            "sender_id": message.sender_id,
+            "chat_id": message.chat_id,
+            "content": message.content,
+            "media": list(message.media or []),
+            "metadata": metadata,
+        }
+    )
+    # This journal is the recovery source of truth, not a mirror of the
+    # bounded in-memory injection queue.  A queued turn can receive more
+    # follow-ups than the live queue accepts; dropping older journal entries
+    # would make those acknowledged user messages unrecoverable after a
+    # gateway restart.  Entries are removed only once their user rows are
+    # committed by ``acknowledge_pending_followups``.
+    session.metadata[PENDING_FOLLOWUPS_KEY] = records
+    session.updated_at = datetime.now()
+    return followup_id
+
+
+def pending_followups(session: Session) -> list[InboundMessage]:
+    """Decode still-unacknowledged follow-ups from durable session metadata."""
+    messages: list[InboundMessage] = []
+    for record in _pending_followup_records(session):
+        followup_id = cast(object, record.get("id"))
+        sender_id = cast(object, record.get("sender_id"))
+        chat_id = cast(object, record.get("chat_id"))
+        content = cast(object, record.get("content"))
+        metadata = cast(object, record.get("metadata"))
+        if (
+            not isinstance(followup_id, str)
+            or not followup_id
+            or not isinstance(sender_id, str)
+            or not sender_id
+            or not isinstance(chat_id, str)
+            or not chat_id
+        ):
+            continue
+        if not isinstance(content, str) or not isinstance(metadata, dict):
+            continue
+        media_value = cast(object, record.get("media"))
+        media = (
+            [item for item in cast(list[object], media_value) if isinstance(item, str)]
+            if isinstance(media_value, list)
+            else []
+        )
+        messages.append(
+            InboundMessage(
+                channel="websocket",
+                sender_id=sender_id,
+                chat_id=chat_id,
+                content=content,
+                media=media,
+                metadata={**cast(dict[str, Any], metadata), PENDING_FOLLOWUP_ID_KEY: followup_id},
+                session_key_override=session.key,
+                require_existing_session=True,
+            )
+        )
+    return messages
+
+
+def acknowledge_pending_followups(session: Session, followup_ids: Iterable[str]) -> None:
+    """Remove journal entries whose user rows were committed to history."""
+    acknowledged = set(followup_ids)
+    if not acknowledged:
+        return
+    records = [record for record in _pending_followup_records(session) if record.get("id") not in acknowledged]
+    if records:
+        session.metadata[PENDING_FOLLOWUPS_KEY] = records
+    else:
+        session.metadata.pop(PENDING_FOLLOWUPS_KEY, None)
+
+
+def _pending_followup_records(session: Session) -> list[dict[str, Any]]:
+    raw = cast(object, session.metadata.get(PENDING_FOLLOWUPS_KEY))
+    if not isinstance(raw, list):
+        return []
+    values = cast(list[object], raw)
+    return [cast(dict[str, Any], value) for value in values if isinstance(value, dict)]
+
+
+def _checkpoint_message_key(message: Mapping[str, Any]) -> tuple[Any, ...]:
+    return (
+        message.get("role"),
+        message.get("content"),
+        message.get("tool_call_id"),
+        message.get("name"),
+        message.get("tool_calls"),
+        message.get("reasoning_content"),
+        message.get("thinking_blocks"),
+    )
+
+
+def _checkpoint_tool_call_ids(
+    value: object,
+    *,
+    result_rows: bool = False,
+) -> list[str] | None:
+    """Validate checkpoint tool rows and return their stable IDs."""
+    if not isinstance(value, list):
+        return None
+    ids: list[str] = []
+    for raw in cast(list[object], value):
+        if not isinstance(raw, dict):
+            return None
+        row = cast(dict[str, Any], raw)
+        id_key = "tool_call_id" if result_rows else "id"
+        call_id = cast(object, row.get(id_key))
+        if not isinstance(call_id, str) or not call_id:
+            return None
+        if result_rows:
+            if row.get("role") != "tool":
+                return None
+        else:
+            function_value = cast(object, row.get("function"))
+            if not isinstance(function_value, dict):
+                return None
+            function = cast(dict[str, Any], function_value)
+            name = cast(object, function.get("name"))
+            if not isinstance(name, str) or not name:
+                return None
+        ids.append(call_id)
+    return ids if len(ids) == len(set(ids)) else None
+
+
+def _runtime_checkpoint_is_well_formed(checkpoint: Mapping[str, Any]) -> bool:
+    """Return whether a checkpoint is safe to offer for continuation.
+
+    Restoration stays tolerant so Dismiss can always clear corrupt state.
+    Continue is stricter: silently dropping a malformed tool result could make
+    the model repeat an external side effect.
+    """
+    assistant_value = cast(object, checkpoint.get("assistant_message"))
+    if not isinstance(assistant_value, dict):
+        return False
+    assistant = cast(dict[str, Any], assistant_value)
+    if assistant.get("role") != "assistant":
+        return False
+
+    completed_ids = _checkpoint_tool_call_ids(
+        cast(object, checkpoint.get("completed_tool_results")),
+        result_rows=True,
+    )
+    pending_ids = _checkpoint_tool_call_ids(
+        cast(object, checkpoint.get("pending_tool_calls")),
+    )
+    if completed_ids is None or pending_ids is None:
+        return False
+    assistant_calls_value = cast(object, assistant.get("tool_calls"))
+    assistant_call_ids = (
+        []
+        if assistant_calls_value is None
+        else _checkpoint_tool_call_ids(assistant_calls_value)
+    )
+    if assistant_call_ids is None:
+        return False
+
+    phase = checkpoint.get("phase")
+    if phase == "final_response":
+        content = cast(object, assistant.get("content"))
+        return (
+            isinstance(content, str)
+            and bool(content.strip())
+            and not assistant_call_ids
+            and not completed_ids
+            and not pending_ids
+        )
+    if phase == "awaiting_tools":
+        return (
+            bool(assistant_call_ids)
+            and not completed_ids
+            and len(assistant_call_ids) == len(pending_ids)
+            and set(assistant_call_ids) == set(pending_ids)
+        )
+    if phase == "tools_completed":
+        return (
+            bool(assistant_call_ids)
+            and not pending_ids
+            and len(assistant_call_ids) == len(completed_ids)
+            and set(assistant_call_ids) == set(completed_ids)
+        )
+    # Error checkpoints have no current producer contract. Treat legacy or
+    # future instances as review-only until their exact persisted shape is
+    # specified; guessing here could make a partial side effect repeat.
+    return False
+
+
+def restore_runtime_checkpoint(session: Session) -> bool:
+    """Materialize the durable checkpoint exactly once and clear it.
+
+    Pending tool calls become explicit interrupted tool results.  They are
+    never executed here.  Provider-native state is retained only for the two
+    checkpoint shapes known to be synchronized with persisted history.
+    """
+    checkpoint = cast(object, session.metadata.get(RUNTIME_CHECKPOINT_KEY))
+    if not isinstance(checkpoint, dict):
+        return False
+    data = cast(dict[str, Any], checkpoint)
+    assistant = cast(object, data.get("assistant_message"))
+    completed_value = cast(object, data.get("completed_tool_results"))
+    pending_value = cast(object, data.get("pending_tool_calls"))
+    completed = cast(list[object], completed_value) if isinstance(completed_value, list) else []
+    pending = cast(list[object], pending_value) if isinstance(pending_value, list) else []
+
+    restored: list[dict[str, Any]] = []
+    if isinstance(assistant, dict):
+        assistant_row = cast(dict[str, Any], assistant)
+    else:
+        assistant_row = {}
+    if assistant_row.get("role") == "assistant":
+        row = dict(assistant_row)
+        row.setdefault("timestamp", datetime.now().isoformat())
+        restored.append(row)
+    for value in completed:
+        if not isinstance(value, dict):
+            continue
+        tool_result = cast(dict[str, Any], value)
+        if tool_result.get("role") != "tool":
+            continue
+        row = dict(tool_result)
+        row.setdefault("timestamp", datetime.now().isoformat())
+        restored.append(row)
+    for value in pending:
+        if not isinstance(value, dict):
+            continue
+        tool_call = cast(dict[str, Any], value)
+        tool_call_id = tool_call.get("id")
+        function_value = cast(object, tool_call.get("function"))
+        if not isinstance(tool_call_id, str) or not tool_call_id:
+            continue
+        function = (
+            cast(dict[str, Any], function_value)
+            if isinstance(function_value, dict)
+            else {}
+        )
+        name = function.get("name")
+        restored.append(
+            {
+                "role": "tool",
+                "tool_call_id": tool_call_id,
+                "name": name if isinstance(name, str) and name else "tool",
+                "content": "Error: Task interrupted before this tool finished.",
+                "timestamp": datetime.now().isoformat(),
+                "_recovery_interrupted": True,
+            }
+        )
+
+    overlap = 0
+    for size in range(min(len(session.messages), len(restored)), 0, -1):
+        if all(
+            _checkpoint_message_key(left) == _checkpoint_message_key(right)
+            for left, right in zip(session.messages[-size:], restored[:size])
+        ):
+            overlap = size
+            break
+    session.messages.extend(restored[overlap:])
+
+    assistant_data = cast(dict[str, Any], assistant) if isinstance(assistant, dict) else None
+    synchronized = (
+        data.get(PROVIDER_STATE_CHECKPOINT_VERSION_KEY)
+        == PROVIDER_STATE_CHECKPOINT_VERSION
+    )
+    phase = data.get("phase")
+    exact_final = (
+        phase == "final_response"
+        and assistant_data is not None
+        and assistant_data.get("role") == "assistant"
+        and not data.get("completed_tool_results")
+        and not data.get("pending_tool_calls")
+    )
+    exact_tools = (
+        phase == "tools_completed"
+        and assistant_data is not None
+        and assistant_data.get("role") == "assistant"
+        and not data.get("pending_tool_calls")
+    )
+    if not (synchronized and (exact_final or exact_tools)):
+        session.provider_state = None
+
+    session.metadata.pop(PENDING_USER_TURN_KEY, None)
+    session.metadata.pop(RUNTIME_CHECKPOINT_KEY, None)
+    session.updated_at = datetime.now()
+    return True
+
+
+def _discard_runtime_checkpoint(session: Session) -> bool:
+    """Drop checkpoint state that cannot be projected into valid history."""
+    if RUNTIME_CHECKPOINT_KEY not in session.metadata:
+        return False
+    session.metadata.pop(RUNTIME_CHECKPOINT_KEY, None)
+    session.provider_state = None
+    session.updated_at = datetime.now()
+    return True
+
+
+def restore_pending_interruption(session: Session, *, superseded: bool = False) -> bool:
+    """Close a persisted user-only turn without pretending it was answered."""
+    if not session.metadata.get(PENDING_USER_TURN_KEY):
+        return False
+    if session.messages and session.messages[-1].get("role") == "user":
+        content = (
+            "Task recovery was superseded by a newer message."
+            if superseded
+            else "Error: Task interrupted before a response was generated."
+        )
+        session.messages.append(
+            {
+                "role": "assistant",
+                "content": content,
+                "timestamp": datetime.now().isoformat(),
+                "_recovery_interrupted": True,
+            }
+        )
+        session.provider_state = None
+        session.updated_at = datetime.now()
+    session.metadata.pop(PENDING_USER_TURN_KEY, None)
+    return True
+
+
+def append_recovery_interruption(session: Session, *, superseded: bool = False) -> None:
+    """Close a restored partial turn whose last durable row is not the user message."""
+    if session.messages and session.messages[-1].get("_recovery_interrupted") is True:
+        return
+    session.messages.append(
+        {
+            "role": "assistant",
+            "content": (
+                "Task recovery was superseded by a newer message."
+                if superseded
+                else "Error: Task recovery was interrupted before completion."
+            ),
+            "timestamp": datetime.now().isoformat(),
+            "_recovery_interrupted": True,
+        }
+    )
+    session.provider_state = None
+    session.updated_at = datetime.now()
+
+
+def recovery_state_from_metadata(metadata: Mapping[str, Any] | None) -> dict[str, Any] | None:
+    """Return a sanitized recovery state suitable for the WebSocket wire."""
+    value = metadata.get(RECOVERY_METADATA_KEY) if metadata else None
+    if not isinstance(value, dict):
+        return None
+    state = cast(dict[str, Any], value)
+    status = state.get("status")
+    recovery_id = state.get("recovery_id")
+    if status not in _RECOVERY_STATUSES or not isinstance(recovery_id, str):
+        return None
+    payload: dict[str, Any] = {"status": status, "recovery_id": recovery_id}
+    reason = state.get("reason")
+    if isinstance(reason, str) and reason:
+        payload["reason"] = reason
+    attempts = state.get("attempts")
+    if isinstance(attempts, int) and attempts >= 0:
+        payload["attempts"] = attempts
+    can_continue = state.get("can_continue")
+    if isinstance(can_continue, bool):
+        payload["can_continue"] = can_continue
+    return payload
+
+
+@dataclasses.dataclass(slots=True)
+class RecoveryCoordinator:
+    """Classify, announce, and gate durable WebUI turn recovery."""
+
+    sessions: SessionManager
+    bus: MessageBus
+    unified_session: bool = False
+    _active_recovery_tasks: dict[str, asyncio.Task[Any]] = dataclasses.field(
+        default_factory=dict,
+        init=False,
+        repr=False,
+    )
+
+    def register_recovery_task(self, session_key: str, task: asyncio.Task[Any]) -> None:
+        """Track the task that owns an explicit recovery continuation."""
+        self._active_recovery_tasks[session_key] = task
+
+    def unregister_recovery_task(self, session_key: str, task: asyncio.Task[Any]) -> None:
+        """Drop a recovery task without removing a newer task for the same session."""
+        if self._active_recovery_tasks.get(session_key) is task:
+            self._active_recovery_tasks.pop(session_key, None)
+
+    async def _cancel_active_recovery(self, session_key: str) -> None:
+        """Stop an explicit continuation before accepting newer user input."""
+        task = self._active_recovery_tasks.get(session_key)
+        if task is None or task is asyncio.current_task() or task.done():
+            return
+        task.cancel()
+        # AgentLoop's cancellation path materializes any partial checkpoint and
+        # releases its pending queue. Wait for that ownership to be released
+        # before the newer message is routed.
+        await asyncio.gather(task, return_exceptions=True)
+
+    async def scan(self) -> None:
+        """Recover every interrupted WebUI session once at gateway startup."""
+        for key in self._recovery_candidates():
+            metadata_payload = self.sessions.read_session_metadata(key)
+            raw_metadata = metadata_payload.get("metadata") if metadata_payload else None
+            metadata = cast(dict[str, Any], raw_metadata) if isinstance(raw_metadata, dict) else {}
+            route = self._websocket_route_for(key, metadata)
+            if route is None:
+                continue
+            unfinished = self._has_unfinished_webui_transcript(key)
+            if not self._needs_recovery(metadata) and not unfinished:
+                continue
+            session = self.sessions.get_or_create(key)
+            try:
+                await self._recover_session(session, route[1])
+                await self._requeue_pending_followups(session)
+            except Exception:
+                logger.exception("failed to recover interrupted WebUI session {}", session.key)
+                state = recovery_state_from_metadata(session.metadata)
+                failed = self._set_state(
+                    session,
+                    status="failed",
+                    recovery_id=cast(str, state["recovery_id"]) if state else uuid4().hex,
+                    attempts=cast(int, state.get("attempts", 0)) if state else 0,
+                    reason="recovery_failed",
+                    can_continue=False,
+                )
+                self.sessions.save(session)
+                await self._publish(route[1], failed)
+
+    def _recovery_candidates(self) -> list[str]:
+        """Discover canonical and transcript-only WebUI sessions cheaply."""
+        candidates = dict.fromkeys(
+            key
+            for item in self.sessions.list_sessions()
+            if isinstance((key := item.get("key")), str)
+        )
+        try:
+            # Imported lazily because the sidebar index also projects recovery
+            # metadata.  The index is the owner of transcript-only discovery;
+            # duplicating its filename and migration rules here would drift.
+            from nanobot.webui.session_list_index import list_webui_sessions
+
+            for item in list_webui_sessions(self.sessions):
+                key = item.get("key")
+                if isinstance(key, str):
+                    candidates.setdefault(key, None)
+        except Exception:
+            # Canonical checkpoint recovery remains available even if the
+            # optional display-history index is corrupt or unavailable.
+            logger.exception("failed to discover transcript-only WebUI sessions")
+        return list(candidates)
+
+    @staticmethod
+    def _needs_recovery(metadata: Mapping[str, Any]) -> bool:
+        if metadata.get(PENDING_USER_TURN_KEY) is True:
+            return True
+        if isinstance(metadata.get(RUNTIME_CHECKPOINT_KEY), dict):
+            return True
+        followups = metadata.get(PENDING_FOLLOWUPS_KEY)
+        if isinstance(followups, list) and len(cast(list[object], followups)) > 0:
+            return True
+        state = recovery_state_from_metadata(metadata)
+        return bool(state and state["status"] in {"resuming", "awaiting_user", "failed"})
+
+    async def admit(self, message: InboundMessage) -> bool:
+        """Reject stale queued recoveries and let new user input supersede them."""
+        recovery_id = message.metadata.get(RECOVERY_INBOUND_METADATA_KEY)
+        if isinstance(recovery_id, str):
+            session = self.sessions.get_or_create(message.session_key)
+            state = recovery_state_from_metadata(session.metadata)
+            return bool(
+                state
+                and state["status"] == "resuming"
+                and state["recovery_id"] == recovery_id
+            )
+        if message.channel != "websocket":
+            return True
+        session = self.sessions.get_or_create(message.session_key)
+        state = recovery_state_from_metadata(session.metadata)
+        if state and state["status"] in {"resuming", "awaiting_user", "failed"}:
+            await self._cancel_active_recovery(message.session_key)
+            restore_runtime_checkpoint(session)
+            if not restore_pending_interruption(session, superseded=True):
+                append_recovery_interruption(session, superseded=True)
+            recovered = self._set_state(
+                session,
+                status="recovered",
+                recovery_id=cast(str, state["recovery_id"]),
+                attempts=cast(int, state.get("attempts", 0)),
+                reason="superseded",
+            )
+            self.sessions.save(session)
+            await self._publish(message.chat_id, recovered)
+        return True
+
+    async def turn_completed(self, session_key: str) -> None:
+        """Resolve a resuming state after the recovered turn commits."""
+        session = self.sessions.get_or_create(session_key)
+        state = recovery_state_from_metadata(session.metadata)
+        if not state or state["status"] != "resuming":
+            return
+        route = self._websocket_route(session)
+        if route is None:
+            return
+        recovered = self._set_state(
+            session,
+            status="recovered",
+            recovery_id=cast(str, state["recovery_id"]),
+            attempts=cast(int, state.get("attempts", 0)),
+            reason="continued",
+        )
+        self.sessions.save(session)
+        await self._publish(route[1], recovered)
+
+    async def handle_action(self, action: str, payload: dict[str, Any]) -> dict[str, Any]:
+        """Apply an authenticated continue/dismiss operation."""
+        chat_id = payload.get("chat_id")
+        recovery_id = payload.get("recovery_id")
+        if not isinstance(chat_id, str) or not chat_id:
+            raise RecoveryActionError("missing chat_id")
+        if not isinstance(recovery_id, str) or not recovery_id:
+            raise RecoveryActionError("missing recovery_id")
+        session = self.sessions.get_or_create(self._session_key(chat_id))
+        state = recovery_state_from_metadata(session.metadata)
+        if not state or state["recovery_id"] != recovery_id:
+            raise RecoveryActionError("recovery state is stale", status=409)
+
+        if action == "dismiss":
+            restore_runtime_checkpoint(session)
+            restore_pending_interruption(session)
+            next_state = self._set_state(
+                session,
+                status="recovered",
+                recovery_id=recovery_id,
+                attempts=cast(int, state.get("attempts", 0)),
+                reason="dismissed",
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, next_state)
+            return next_state
+        if action != "continue":
+            raise RecoveryActionError("unknown recovery action")
+        if state["status"] not in {"awaiting_user", "failed"}:
+            raise RecoveryActionError("recovery is not waiting for confirmation", status=409)
+        if state.get("can_continue") is False:
+            raise RecoveryActionError("recovery context is unavailable", status=409)
+        next_state = self._set_state(
+            session,
+            status="resuming",
+            recovery_id=recovery_id,
+            attempts=cast(int, state.get("attempts", 0)) + 1,
+            reason="user_confirmed",
+            resume_message_count=len(session.messages),
+        )
+        self.sessions.save(session)
+        await self._publish(chat_id, next_state)
+        await self._queue_continuation(session, chat_id, next_state)
+        return next_state
+
+    async def _recover_session(self, session: Session, chat_id: str) -> None:
+        checkpoint_value = cast(object, session.metadata.get(RUNTIME_CHECKPOINT_KEY))
+        checkpoint = (
+            cast(dict[str, Any], checkpoint_value)
+            if isinstance(checkpoint_value, dict)
+            else None
+        )
+        pending = session.metadata.get(PENDING_USER_TURN_KEY) is True
+        state = recovery_state_from_metadata(session.metadata)
+        if not pending and checkpoint is None:
+            if state and state["status"] == "resuming":
+                resume_count = self._resume_message_count(session)
+                if resume_count is not None and len(session.messages) > resume_count:
+                    next_state = self._set_state(
+                        session,
+                        status="recovered",
+                        recovery_id=cast(str, state["recovery_id"]),
+                        attempts=cast(int, state.get("attempts", 0)),
+                        reason="committed",
+                    )
+                else:
+                    next_state = self._set_state(
+                        session,
+                        status="awaiting_user",
+                        recovery_id=cast(str, state["recovery_id"]),
+                        attempts=cast(int, state.get("attempts", 1)),
+                        reason="loop_guard",
+                    )
+                self.sessions.save(session)
+                await self._publish(chat_id, next_state)
+            elif self._has_unfinished_webui_transcript(session.key):
+                # A normal last-client shutdown can materialize the checkpoint
+                # before the process exits.  In that path there is no pending
+                # marker left to classify, but the append-only transcript still
+                # contains an activity row without a turn_end.  Treat it as an
+                # interrupted turn instead of letting the UI resurrect it as a
+                # forever-running spinner.
+                can_continue = self._has_saved_continuation_context(session)
+                waiting = self._set_state(
+                    session,
+                    status="awaiting_user",
+                    recovery_id=uuid4().hex,
+                    attempts=0,
+                    reason=(
+                        "interrupted_with_saved_context"
+                        if can_continue
+                        else "interrupted_without_checkpoint"
+                    ),
+                    can_continue=can_continue,
+                )
+                self.sessions.save(session)
+                await self._publish(chat_id, waiting)
+            return
+        if state and state["status"] in {"awaiting_user", "failed"}:
+            await self._publish(chat_id, state)
+            return
+        if state and state["status"] == "resuming":
+            restore_runtime_checkpoint(session)
+            restore_pending_interruption(session)
+            waiting = self._set_state(
+                session,
+                status="awaiting_user",
+                recovery_id=cast(str, state["recovery_id"]),
+                attempts=cast(int, state.get("attempts", 1)),
+                reason="loop_guard",
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, waiting)
+            return
+
+        recovery_id = uuid4().hex
+        phase = checkpoint.get("phase") if checkpoint is not None else None
+        pending_calls = checkpoint.get("pending_tool_calls") if checkpoint is not None else None
+        if checkpoint is not None and phase not in _KNOWN_CHECKPOINT_PHASES:
+            _discard_runtime_checkpoint(session)
+            restore_pending_interruption(session)
+            waiting = self._set_state(
+                session,
+                status="awaiting_user",
+                recovery_id=recovery_id,
+                attempts=0,
+                reason="checkpoint_unknown",
+                can_continue=False,
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, waiting)
+            return
+        if checkpoint is not None and not _runtime_checkpoint_is_well_formed(checkpoint):
+            _discard_runtime_checkpoint(session)
+            restore_pending_interruption(session)
+            waiting = self._set_state(
+                session,
+                status="awaiting_user",
+                recovery_id=recovery_id,
+                attempts=0,
+                reason="checkpoint_invalid",
+                can_continue=False,
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, waiting)
+            return
+        if phase == "final_response":
+            restore_runtime_checkpoint(session)
+            recovered = self._set_state(
+                session,
+                status="recovered",
+                recovery_id=recovery_id,
+                attempts=0,
+                reason="answer_restored",
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, recovered)
+            return
+        if phase in _UNCERTAIN_TOOL_PHASES or pending_calls:
+            restore_runtime_checkpoint(session)
+            waiting = self._set_state(
+                session,
+                status="awaiting_user",
+                recovery_id=recovery_id,
+                attempts=0,
+                reason="tool_state_unknown",
+            )
+            self.sessions.save(session)
+            await self._publish(chat_id, waiting)
+            return
+        # A gateway restart is a lifecycle boundary.  Never enqueue model work
+        # implicitly: even a synchronized checkpoint may sit next to an
+        # external side effect that the user should review first.  The final
+        # answer path above only restores persisted output; it never executes.
+        restore_runtime_checkpoint(session)
+        waiting = self._set_state(
+            session,
+            status="awaiting_user",
+            recovery_id=recovery_id,
+            attempts=0,
+            reason="restart_requires_confirmation",
+        )
+        self.sessions.save(session)
+        await self._publish(chat_id, waiting)
+
+    async def _queue_continuation(
+        self,
+        session: Session,
+        chat_id: str,
+        state: Mapping[str, Any],
+    ) -> None:
+        recovery_id = cast(str, state["recovery_id"])
+        await self.bus.publish_inbound(
+            InboundMessage(
+                channel="websocket",
+                sender_id="system:recovery",
+                chat_id=chat_id,
+                content=(
+                    "Continue the interrupted request from the saved conversation context. "
+                    "Do not repeat completed work or mention the restart unless it affects the answer."
+                ),
+                metadata={
+                    "webui": True,
+                    "_wants_stream": True,
+                    WEBUI_TURN_METADATA_KEY: f"recovery:{recovery_id}",
+                    RECOVERY_INBOUND_METADATA_KEY: recovery_id,
+                    turn_continuation.INTERNAL_CONTINUATION_META: True,
+                    turn_continuation.SKIP_USER_PERSIST_META: True,
+                },
+                session_key_override=session.key,
+                require_existing_session=True,
+            )
+        )
+
+    async def _requeue_pending_followups(self, session: Session) -> None:
+        """Return durable live-turn follow-ups to the bus after a restart."""
+        for message in pending_followups(session):
+            await self.bus.publish_inbound(message)
+
+    @staticmethod
+    def _resume_message_count(session: Session) -> int | None:
+        raw_value = cast(object, session.metadata.get(RECOVERY_METADATA_KEY))
+        value = cast(dict[str, Any], raw_value) if isinstance(raw_value, dict) else None
+        if value is None:
+            return None
+        count = value.get("resume_message_count")
+        return count if isinstance(count, int) and count >= 0 else None
+
+    async def _publish(
+        self,
+        chat_id: str,
+        state: Mapping[str, Any],
+    ) -> None:
+        """Publish the recovery state and invalidate its sidebar projection."""
+        await self.bus.publish_outbound(
+            outbound_message_for_event(
+                channel="websocket",
+                chat_id=chat_id,
+                event=RecoveryStateEvent(
+                    status=cast(str, state["status"]),
+                    recovery_id=cast(str, state["recovery_id"]),
+                    reason=cast(str | None, state.get("reason")),
+                    attempts=cast(int, state.get("attempts", 0)),
+                    can_continue=cast(bool | None, state.get("can_continue")),
+                ),
+            )
+        )
+        await self.bus.publish_outbound(
+            outbound_message_for_event(
+                channel="websocket",
+                chat_id=chat_id,
+                event=SessionUpdatedEvent(scope="thread"),
+            )
+        )
+
+    @staticmethod
+    def _set_state(
+        session: Session,
+        *,
+        status: str,
+        recovery_id: str,
+        attempts: int,
+        reason: str,
+        resume_message_count: int | None = None,
+        can_continue: bool = True,
+    ) -> dict[str, Any]:
+        state = {
+            "status": status,
+            "recovery_id": recovery_id,
+            "attempts": max(0, attempts),
+            "reason": reason,
+            "updated_at": datetime.now().isoformat(),
+        }
+        if not can_continue:
+            state["can_continue"] = False
+        if resume_message_count is not None:
+            state["resume_message_count"] = max(0, resume_message_count)
+        session.metadata[RECOVERY_METADATA_KEY] = state
+        session.updated_at = datetime.now()
+        return state
+
+    def _session_key(self, chat_id: str) -> str:
+        return UNIFIED_SESSION_KEY if self.unified_session else f"websocket:{chat_id}"
+
+    @staticmethod
+    def _has_unfinished_webui_transcript(session_key: str) -> bool:
+        """Detect a stale WebUI activity tail after an unclean gateway stop.
+
+        The transcript is intentionally consulted only as a last-resort signal:
+        a durable pending turn or runtime checkpoint always takes precedence.
+        This keeps browser disconnects harmless while preventing a materialized
+        partial turn from being presented as active forever after a restart.
+        """
+        try:
+            from nanobot.webui.transcript import has_unfinished_transcript_tail
+
+            return has_unfinished_transcript_tail(session_key)
+        except (OSError, ValueError, TypeError):
+            # Recovery must fail closed if the optional display transcript is
+            # corrupt or unavailable; the normal checkpoint path still applies.
+            return False
+
+    @staticmethod
+    def _has_saved_continuation_context(session: Session) -> bool:
+        """Whether an interrupted turn left model-visible context to continue from."""
+        last_user = next(
+            (
+                index
+                for index in range(len(session.messages) - 1, -1, -1)
+                if session.messages[index].get("role") == "user"
+            ),
+            None,
+        )
+        if last_user is None:
+            return False
+        tail = session.messages[last_user + 1 :]
+        return bool(tail) and (
+            tail[-1].get("role") == "tool"
+            or any(message.get("_recovery_interrupted") is True for message in tail)
+            or any(
+                message.get("role") == "assistant" and bool(message.get("tool_calls"))
+                for message in tail
+            )
+        )
+
+    @staticmethod
+    def _websocket_route(session: Session) -> tuple[str, str] | None:
+        return RecoveryCoordinator._websocket_route_for(session.key, session.metadata)
+
+    @staticmethod
+    def _websocket_route_for(
+        session_key: str,
+        metadata: Mapping[str, Any],
+    ) -> tuple[str, str] | None:
+        if session_key.startswith("websocket:"):
+            chat_id = session_key.split(":", 1)[1]
+            return ("websocket", chat_id) if chat_id else None
+        if session_key == UNIFIED_SESSION_KEY:
+            route = last_channel_from_metadata(metadata)
+            if route and route[0] == "websocket":
+                return route
+        return None

nanobot/session/webui_turns.py

@@ -43,6 +43,7 @@ from nanobot.runtime_context import public_history_message
 from nanobot.session.goal_state import goal_state_ws_blob
 from nanobot.session.history_visibility import is_hidden_history_message
 from nanobot.session.manager import Session, SessionManager
+from nanobot.session.recovery import RecoveryCoordinator
 from nanobot.session.session_handles import session_handle_for_name
 from nanobot.session.session_messages import (
     SessionMessageEnvelope,
@@ -511,6 +512,7 @@ class WebuiTurnCoordinator:
     bus: MessageBus
     sessions: SessionManager
     schedule_background: Callable[[Awaitable[None]], None]
+    recovery: RecoveryCoordinator | None = None
 
     def subscribe(self, runtime_events: RuntimeEventBus) -> Callable[[], None]:
         """Subscribe this coordinator to runtime events."""
@@ -654,6 +656,8 @@ class WebuiTurnCoordinator:
                 event.runtime.context_window_tokens if event.runtime is not None else None
             ),
         )
+        if self.recovery is not None:
+            await self.recovery.turn_completed(event.context.session_key)
         self._schedule_title_update_from_event(event)
 
     async def _handle_goal_state_changed(self, event: GoalStateChanged) -> None:

nanobot/webui/gateway_services.py

@@ -69,6 +69,7 @@ def build_gateway_services(
     mcp_runtime_status: Callable[[], Mapping[str, str]] | None = None,
     mcp_reload: Callable[[], Awaitable[dict[str, Any]]] | None = None,
     skill_state_action: Callable[[set[str]], None] | None = None,
+    recovery_action: Callable[[str, dict[str, Any]], Awaitable[dict[str, Any]]] | None = None,
     logger: Any = default_logger,
 ) -> GatewayServices:
     settings = WebUISettingsServices.create(
@@ -131,6 +132,7 @@ def build_gateway_services(
         mcp_runtime_status=mcp_runtime_status,
         mcp_reload=mcp_reload,
         skill_state_action=skill_state_action,
+        recovery_action=recovery_action,
         log=logger,
     )
     return GatewayServices(

nanobot/webui/session_list_index.py

@@ -31,8 +31,9 @@ from nanobot.session.manager import (
     _metadata_title,  # pyright: ignore[reportPrivateUsage]
 )
 from nanobot.session.model_selection import model_preset_from_metadata
+from nanobot.session.recovery import recovery_state_from_metadata
 
-_INDEX_VERSION = 7
+_INDEX_VERSION = 8
 _INDEX_FILENAME = ".webui_session_index.json"
 _MODEL_PRESET_FIELD = "model_preset"
 _ROW_SOURCE_FIELD = "_source"
@@ -245,6 +246,7 @@ def _public_row(sessions_dir: Path, webui_dir: Path, row: dict[str, Any]) -> dic
         "title": row.get("title", ""),
         "preview": row.get("preview", ""),
         _MODEL_PRESET_FIELD: row.get(_MODEL_PRESET_FIELD),
+        "recovery_state": row.get("recovery_state"),
         _WORKSPACE_SCOPE_PRESENT_FIELD: row.get(_WORKSPACE_SCOPE_PRESENT_FIELD, False),
         _WORKSPACE_SCOPE_VALUE_FIELD: row.get(_WORKSPACE_SCOPE_VALUE_FIELD),
         "path": str(path),
@@ -485,6 +487,7 @@ def _indexed_row_for_session(session: Session, path: Path, webui_dir: Path) -> d
         "title": _metadata_title(session.metadata),
         "preview": _preview_from_messages(session.messages),
         _MODEL_PRESET_FIELD: model_preset_from_metadata(session.metadata),
+        "recovery_state": recovery_state_from_metadata(session.metadata),
         **_indexed_workspace_scope_fields(session.metadata),
         _ROW_SOURCE_FIELD: _SESSION_SOURCE,
         "file": path.name,
@@ -601,6 +604,7 @@ def _scan_transcript_row(
         "title": "",
         "preview": preview or fallback_preview,
         _MODEL_PRESET_FIELD: None,
+        "recovery_state": None,
         **_indexed_workspace_scope_fields({}),
         _ROW_SOURCE_FIELD: _TRANSCRIPT_SOURCE,
         "file": stem,
@@ -687,6 +691,7 @@ def _scan_session_row(
                 "title": _metadata_title(metadata),
                 "preview": preview or fallback_preview,
                 _MODEL_PRESET_FIELD: model_preset_from_metadata(metadata),
+                "recovery_state": recovery_state_from_metadata(metadata),
                 **_indexed_workspace_scope_fields(metadata),
                 _ROW_SOURCE_FIELD: _SESSION_SOURCE,
                 "file": path.name,

nanobot/webui/transcript.py

@@ -2541,6 +2541,19 @@ def has_pending_tool_calls(
     return False
 
 
+def has_unfinished_transcript_tail(session_key: str) -> bool:
+    """Return whether the active transcript ends in an unfinished turn.
+
+    Recovery runs at gateway startup and only needs the newest, still-active
+    turn. Completed turns are rotated into immutable segment files, so reading
+    every historical segment here would make restart cost grow with the full
+    conversation history.
+    """
+    return has_pending_tool_calls(
+        _read_transcript_file(webui_transcript_path(session_key))
+    )
+
+
 def completed_turn_ids(lines: list[dict[str, Any]]) -> list[str]:
     """Return stable identities for turns with an explicitly persisted completion."""
     completed: list[str] = []

nanobot/webui/ws_http.py

@@ -29,6 +29,7 @@ from nanobot.cron.session_turns import is_bound_cron_job
 from nanobot.cron.types import CronJob, CronSchedule
 from nanobot.security.workspace_access import WorkspaceScope
 from nanobot.session.manager import SessionManager
+from nanobot.session.recovery import RecoveryActionError
 from nanobot.session.session_handles import (
     SessionHandleResolver,
 )
@@ -145,6 +146,8 @@ _WEBUI_MUTATION_PATHS = {
     "skill.delete": "/api/webui/skills/delete",
     "sidebar.update": "/api/webui/sidebar-state/update",
     "workspace.pick_folder": "/api/workspaces/pick-folder",
+    "recovery.continue": "/api/webui/recovery/continue",
+    "recovery.dismiss": "/api/webui/recovery/dismiss",
     "settings.agent.update": "/api/settings/update",
     "settings.model_configuration.create": "/api/settings/model-configurations/create",
     "settings.model_configuration.update": "/api/settings/model-configurations/update",
@@ -323,6 +326,9 @@ class GatewayHTTPHandler:
         mcp_runtime_status: Callable[[], Mapping[str, str]] | None = None,
         mcp_reload: Callable[[], Awaitable[dict[str, Any]]] | None = None,
         skill_state_action: Callable[[set[str]], None] | None = None,
+        recovery_action: (
+            Callable[[str, dict[str, Any]], Awaitable[dict[str, Any]]] | None
+        ) = None,
         log: Any = logger,
     ) -> None:
         self.config = config
@@ -340,6 +346,7 @@ class GatewayHTTPHandler:
             disabled_skills if disabled_skills is not None else set()
         )
         self.skill_state_action = skill_state_action
+        self.recovery_action = recovery_action
         self._skill_install_lock = asyncio.Lock()
         self._folder_picker_lock = asyncio.Lock()
         self.cron_service = cron_service
@@ -454,6 +461,8 @@ class GatewayHTTPHandler:
             return True
         if re.match(r"^/api/webui/automations/(enable|disable|delete|run|update)$", path):
             return True
+        if path in {"/api/webui/recovery/continue", "/api/webui/recovery/dismiss"}:
+            return True
         return path in {
             "/api/webui/skills/install",
             "/api/webui/skills/update",
@@ -507,6 +516,11 @@ class GatewayHTTPHandler:
         if response is not None:
             return response
 
+        # Recovery routes
+        response = await self._dispatch_recovery_route(request, got)
+        if response is not None:
+            return response
+
         # Session routes
         response = await self._dispatch_session_routes(request, got)
         if response is not None:
@@ -700,6 +714,27 @@ class GatewayHTTPHandler:
 
         return None
 
+    async def _dispatch_recovery_route(
+        self,
+        request: WsRequest,
+        path: str,
+    ) -> Response | None:
+        match = re.fullmatch(r"/api/webui/recovery/(continue|dismiss)", path)
+        if match is None:
+            return None
+        if not getattr(request, _WEBUI_MUTATION_REQUEST_ATTR, False):
+            return _http_error(405, "WebUI recovery actions require an authenticated WebSocket")
+        if self.recovery_action is None:
+            return _http_error(503, "WebUI recovery is unavailable")
+        payload = _mutation_payload(request)
+        if payload is None:
+            return _http_error(400, "invalid recovery payload")
+        try:
+            result = await self.recovery_action(match.group(1), payload)
+        except RecoveryActionError as exc:
+            return _http_error(exc.status, str(exc))
+        return _http_json_response(result)
+
     async def _handle_session_context_get(self, request: WsRequest, key: str) -> Response:
         if not self.check_api_token(request):
             return _http_error(401, "Unauthorized")
@@ -746,6 +781,10 @@ class GatewayHTTPHandler:
                 for k, v in s.items()
                 if k != "path" and k not in WEBUI_SESSION_INDEX_INTERNAL_FIELDS
             }
+            # Keep the additive recovery field absent for ordinary sessions so
+            # older clients and compact list responses stay unchanged.
+            if row.get("recovery_state") is None:
+                row.pop("recovery_state", None)
             chat_id = key.split(":", 1)[1]
             started_at = websocket_turn_wall_started_at(chat_id)
             if started_at is not None:

tests/agent/test_loop_save_turn.py

@@ -36,6 +36,7 @@ from nanobot.session.keys import (
     UNIFIED_SESSION_KEY,
 )
 from nanobot.session.manager import Session
+from nanobot.session.recovery import PENDING_FOLLOWUP_ID_KEY, PENDING_FOLLOWUPS_KEY
 from nanobot.session.turn_continuation import (
     INTERNAL_CONTINUATION_META,
     INTERNAL_CONTINUATION_RUN_STARTED_AT_META,
@@ -161,6 +162,35 @@ def test_persist_cron_turn_uses_distinct_history_marker(tmp_path: Path) -> None:
     assert message["cron_prompt_ref"] == prompt_ref
 
 
+def test_persist_user_message_acknowledges_durable_followup(tmp_path: Path) -> None:
+    loop = _make_full_loop(tmp_path)
+    session = loop.sessions.get_or_create("websocket:chat")
+    session.metadata[PENDING_FOLLOWUPS_KEY] = [
+        {
+            "id": "followup-1",
+            "sender_id": "user",
+            "chat_id": "chat",
+            "content": "queued while busy",
+            "media": [],
+            "metadata": {},
+        }
+    ]
+
+    persisted = loop._persist_user_message_early(
+        InboundMessage(
+            channel="websocket",
+            sender_id="user",
+            chat_id="chat",
+            content="queued while busy",
+            metadata={PENDING_FOLLOWUP_ID_KEY: "followup-1"},
+        ),
+        session,
+    )
+
+    assert persisted is True
+    assert PENDING_FOLLOWUPS_KEY not in session.metadata
+
+
 def test_persist_local_trigger_turn_uses_hidden_automation_marker(tmp_path: Path) -> None:
     loop = _make_full_loop(tmp_path)
     session = loop.sessions.get_or_create("websocket:auto")
@@ -381,6 +411,34 @@ def test_save_turn_keeps_multimodal_runtime_context_for_model_replay() -> None:
     assert public_history_message(session.messages[0])["content"] == []
 
 
+def test_save_turn_acknowledges_every_merged_recovery_followup() -> None:
+    """Persisting a merged injected row retires every durable follow-up ID."""
+    loop = _mk_loop()
+    session = Session(
+        key="test:recovery-followups",
+        metadata={
+            PENDING_FOLLOWUPS_KEY: [
+                {"id": "first"},
+                {"id": "second"},
+            ]
+        },
+    )
+
+    loop._save_turn(
+        session,
+        [
+            {
+                "role": "user",
+                "content": "first\n\nsecond",
+                PENDING_FOLLOWUP_ID_KEY: ["first", "second"],
+            }
+        ],
+        skip=0,
+    )
+
+    assert PENDING_FOLLOWUPS_KEY not in session.metadata
+
+
 def test_save_turn_keeps_image_placeholder_and_runtime_context() -> None:
     loop = _mk_loop()
     session = Session(key="test:image")

tests/agent/test_runner_injections.py

@@ -26,7 +26,7 @@ def _make_injection_callback(queue: asyncio.Queue):
     return inject_cb
 
 
-def _make_loop(tmp_path):
+def _make_loop(tmp_path, *, recovery_admission=None):
     from nanobot.agent.loop import AgentLoop
     from nanobot.bus.queue import MessageBus
 
@@ -39,7 +39,12 @@ def _make_loop(tmp_path):
          patch("nanobot.agent.loop.SubagentManager") as mock_sub_mgr:
         mock_sub_mgr.return_value.cancel_by_session = AsyncMock(return_value=0)
         mock_sub_mgr.return_value.close = AsyncMock()
-        loop = AgentLoop(bus=bus, provider=provider, workspace=tmp_path)
+        loop = AgentLoop(
+            bus=bus,
+            provider=provider,
+            workspace=tmp_path,
+            recovery_admission=recovery_admission,
+        )
     return loop
 
 @pytest.mark.asyncio
@@ -759,6 +764,20 @@ async def test_runner_merges_multiple_injected_user_messages_without_losing_medi
     )
 
 
+def test_runner_merge_keeps_all_recovery_followup_ids() -> None:
+    """Merged follow-ups stay acknowledged together after a later save."""
+    from nanobot.agent.runner import AgentRunner
+    from nanobot.session.recovery import PENDING_FOLLOWUP_ID_KEY
+
+    messages = [{"role": "user", "content": "first", PENDING_FOLLOWUP_ID_KEY: "one"}]
+    AgentRunner._append_injected_messages(
+        messages,
+        [{"role": "user", "content": "second", PENDING_FOLLOWUP_ID_KEY: "two"}],
+    )
+
+    assert messages[-1][PENDING_FOLLOWUP_ID_KEY] == ["one", "two"]
+
+
 def test_runner_merge_preserves_runtime_markers_with_media() -> None:
     from nanobot.agent.runner import AgentRunner
     from nanobot.runtime_context import (
@@ -967,6 +986,71 @@ async def test_followup_routed_to_pending_queue(tmp_path):
     assert queued_msg.session_key == UNIFIED_SESSION_KEY
 
 
+@pytest.mark.asyncio
+async def test_websocket_followup_is_admitted_before_recovery_queue(tmp_path):
+    """Recovery admission runs before a newer WebUI message is injected."""
+    from nanobot.bus.events import InboundMessage
+
+    admission = MagicMock()
+    admission.admit = AsyncMock(return_value=True)
+    loop = _make_loop(tmp_path, recovery_admission=admission)
+    loop._dispatch = AsyncMock()  # type: ignore[method-assign]
+
+    session_key = "websocket:chat"
+    pending = asyncio.Queue(maxsize=20)
+    loop._pending_queues[session_key] = pending
+
+    run_task = asyncio.create_task(loop.run())
+    msg = InboundMessage(
+        channel="websocket",
+        sender_id="u",
+        chat_id="chat",
+        content="new request",
+    )
+    await loop.bus.publish_inbound(msg)
+
+    queued_msg = await asyncio.wait_for(pending.get(), timeout=2)
+    admission.admit.assert_awaited_once_with(msg)
+    assert queued_msg.content == msg.content
+    assert queued_msg.metadata["_recovery_followup_id"]
+
+    loop.stop()
+    await asyncio.wait_for(run_task, timeout=2)
+
+
+@pytest.mark.asyncio
+async def test_unified_websocket_followup_admits_effective_session(tmp_path):
+    """Recovery admission and the pending queue must use the same session key."""
+    from nanobot.bus.events import InboundMessage
+    from nanobot.session.keys import UNIFIED_SESSION_KEY
+
+    admission = MagicMock()
+    admission.admit = AsyncMock(return_value=True)
+    loop = _make_loop(tmp_path, recovery_admission=admission)
+    loop._unified_session = True
+    loop._dispatch = AsyncMock()  # type: ignore[method-assign]
+
+    pending = asyncio.Queue(maxsize=20)
+    loop._pending_queues[UNIFIED_SESSION_KEY] = pending
+
+    run_task = asyncio.create_task(loop.run())
+    msg = InboundMessage(
+        channel="websocket",
+        sender_id="u",
+        chat_id="chat",
+        content="new request",
+    )
+    await loop.bus.publish_inbound(msg)
+
+    queued_msg = await asyncio.wait_for(pending.get(), timeout=2)
+    admitted_msg = admission.admit.await_args.args[0]
+    assert admitted_msg.session_key == UNIFIED_SESSION_KEY
+    assert queued_msg.session_key == UNIFIED_SESSION_KEY
+
+    loop.stop()
+    await asyncio.wait_for(run_task, timeout=2)
+
+
 @pytest.mark.asyncio
 async def test_mid_turn_subagent_result_does_not_resolve_a_new_turn_route(tmp_path):
     """Injected results stay inside the active turn instead of opening a side turn."""
@@ -1314,6 +1398,51 @@ async def test_pending_queue_full_falls_back_to_queued_task(tmp_path):
     assert pending.qsize() == 1
 
 
+@pytest.mark.asyncio
+async def test_pending_queue_overflow_keeps_websocket_followup_durable(tmp_path):
+    """Fallback dispatch must not acknowledge a WebUI message before it commits."""
+    from nanobot.bus.events import InboundMessage
+    from nanobot.session.manager import Session
+    from nanobot.session.recovery import pending_followups
+
+    loop = _make_loop(tmp_path)
+    dispatched = asyncio.Event()
+    release_dispatch = asyncio.Event()
+
+    async def _dispatch(_msg):
+        dispatched.set()
+        await release_dispatch.wait()
+
+    loop._dispatch = AsyncMock(side_effect=_dispatch)  # type: ignore[method-assign]
+    session = Session(key="websocket:c")
+    loop.sessions.get_or_create.return_value = session
+    pending = asyncio.Queue(maxsize=1)
+    pending.put_nowait(
+        InboundMessage(channel="websocket", sender_id="u", chat_id="c", content="already queued")
+    )
+    loop._pending_queues["websocket:c"] = pending
+
+    run_task = asyncio.create_task(loop.run())
+    await loop.bus.publish_inbound(
+        InboundMessage(
+            channel="websocket",
+            sender_id="u",
+            chat_id="c",
+            content="durable follow-up",
+            metadata={"webui": True},
+        )
+    )
+    await asyncio.wait_for(dispatched.wait(), timeout=2)
+
+    assert [message.content for message in pending_followups(session)] == ["durable follow-up"]
+    dispatched_msg = loop._dispatch.await_args.args[0]
+    assert dispatched_msg.metadata["_recovery_followup_id"]
+
+    release_dispatch.set()
+    loop.stop()
+    await asyncio.wait_for(run_task, timeout=2)
+
+
 @pytest.mark.asyncio
 async def test_dispatch_republishes_leftover_queue_messages(tmp_path):
     """Messages left in the pending queue after _dispatch are re-published to the bus.

tests/agent/test_stop_preserves_context.py

@@ -161,3 +161,25 @@ async def test_dispatch_cancellation_restores_checkpoint():
         "Checkpoint metadata should be cleared after restore"
     assert loop.sessions.save.called, \
         "Session should be persisted so the restored state survives process restart"
+
+
+@pytest.mark.asyncio
+async def test_dispatch_cancellation_keeps_checkpoint_for_gateway_shutdown(tmp_path: Path) -> None:
+    """Gateway shutdown preserves the checkpoint; an explicit stop restores it."""
+    loop = _make_loop(tmp_path)
+    loop.preserve_inflight_turns_on_shutdown()
+    loop._restore_runtime_checkpoint = MagicMock()  # type: ignore[method-assign]
+
+    async def _cancel(*_args: object, **_kwargs: object) -> None:
+        raise asyncio.CancelledError()
+
+    loop._process_message = _cancel  # type: ignore[method-assign]
+
+    from nanobot.bus.events import InboundMessage
+
+    with pytest.raises(asyncio.CancelledError):
+        await loop._dispatch(
+            InboundMessage(channel="test", sender_id="u1", chat_id="c1", content="work")
+        )
+
+    loop._restore_runtime_checkpoint.assert_not_called()

tests/channels/test_channel_plugins.py

@@ -3721,6 +3721,27 @@ async def test_notify_restart_done_waits_until_channel_starts():
     assert sent_msg.content.startswith("Restart completed")
 
 
+@pytest.mark.asyncio
+async def test_websocket_restart_notice_does_not_overwrite_recovery_state():
+    """WebSocket attach/recovery events already own reconnect state."""
+    fake_config = SimpleNamespace(
+        channels=ChannelsConfig(),
+        providers=SimpleNamespace(groq=SimpleNamespace(api_key="")),
+    )
+    mgr = ChannelManager.__new__(ChannelManager)
+    mgr.config = fake_config
+    mgr.bus = MessageBus()
+    channel = _StartableChannel(fake_config, mgr.bus)
+    channel._running = True
+    mgr.channels = {"websocket": channel}
+    mgr._send_with_retry = AsyncMock()
+
+    notice = RestartNotice(channel="websocket", chat_id="chat", started_at_raw="100.0")
+    await mgr._send_restart_notice_when_started(notice)
+
+    mgr._send_with_retry.assert_not_awaited()
+
+
 @pytest.mark.asyncio
 async def test_restart_notice_retries_until_running_channel_accepts_delivery():
     """A running flag must not make an early transport failure final."""

tests/cli/test_commands.py

@@ -102,6 +102,19 @@ class _GatewayAgentContractStub:
     ) -> OutboundMessage | None:
         return None
 
+    def preserve_inflight_turns_on_shutdown(self) -> None:
+        return None
+
+
+class _EmptyGatewaySessionManager:
+    """Minimal session-manager contract for gateway assembly tests."""
+
+    def list_sessions(self) -> list[dict[str, object]]:
+        return []
+
+    def flush_all(self) -> int:
+        return 0
+
 
 def test_gateway_signal_handler_first_signal_stops_and_second_forces() -> None:
     class _FakeLoop:
@@ -2756,7 +2769,7 @@ def _patch_serve_runtime(monkeypatch, config: Config, seen: dict[str, object]) -
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
     )
     monkeypatch.setattr("nanobot.cli.commands.AgentLoop", _FakeAgentLoop)
     monkeypatch.setattr("nanobot.api.server.create_app", _fake_create_app)
@@ -2823,7 +2836,7 @@ def test_gateway_uses_workspace_directory_for_cron_store(monkeypatch, tmp_path:
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
         cron_service=_StopCron,
     )
 
@@ -3329,7 +3342,7 @@ def test_gateway_workspace_override_does_not_migrate_legacy_cron(
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
         cron_service=_StopCron,
         get_cron_dir=lambda: legacy_dir,
     )
@@ -3368,7 +3381,7 @@ def test_gateway_custom_config_workspace_does_not_migrate_legacy_cron(
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
         cron_service=_StopCron,
         get_cron_dir=lambda: legacy_dir,
     )
@@ -3569,7 +3582,7 @@ def test_gateway_health_endpoint_binds_and_serves_expected_responses(
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
     )
     monkeypatch.setattr("nanobot.cli.gateway_runtime.AgentLoop", _FakeAgentLoop)
     monkeypatch.setattr("nanobot.channels.manager.ChannelManager", _FakeChannelManager)
@@ -3702,6 +3715,9 @@ def test_gateway_agent_task_owns_initial_mcp_provider_close(
         async def aclose(self) -> None:
             seen["agent_closed"] = True
 
+        def preserve_inflight_turns_on_shutdown(self) -> None:
+            seen["inflight_turns_preserved"] = True
+
         def stop(self) -> None:
             seen["agent_stopped"] = True
 
@@ -3771,7 +3787,7 @@ def test_gateway_agent_task_owns_initial_mcp_provider_close(
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
     )
     monkeypatch.setattr("nanobot.cli.gateway_runtime.AgentLoop", _FakeAgentLoop)
     monkeypatch.setattr("nanobot.cli.gateway_runtime.MCPProvider", _FakeMCPProvider)
@@ -3783,6 +3799,7 @@ def test_gateway_agent_task_owns_initial_mcp_provider_close(
 
     assert result.exit_code == 0
     assert seen["agent_stopped"] is True
+    assert seen["inflight_turns_preserved"] is True
     assert seen["agent_closed"] is True
     assert seen["agent_task_cleaned_up"] is True
     assert seen["channels_stopped"] is True
@@ -3894,7 +3911,7 @@ def test_gateway_shutdown_event_exits_forever_runtime_tasks(
         monkeypatch,
         config,
         message_bus=lambda: object(),
-        session_manager=lambda _workspace: object(),
+        session_manager=lambda _workspace: _EmptyGatewaySessionManager(),
     )
     monkeypatch.setattr("nanobot.cli.gateway_runtime.AgentLoop", _FakeAgentLoop)
     monkeypatch.setattr("nanobot.channels.manager.ChannelManager", _FakeChannelManager)

tests/gateway/test_runtime.py

@@ -18,6 +18,7 @@ from nanobot.gateway import (
     GatewayRuntimePaths,
     GatewayStartOptions,
     GatewayStatus,
+    RuntimeResult,
 )
 from nanobot.gateway.runtime import monitor_gateway_clients
 from nanobot.process_runtime import process_is_running
@@ -454,6 +455,33 @@ def test_restart_does_not_detach_a_foreground_gateway(tmp_path, monkeypatch):
     assert result.message == "gateway_foreground_restart_required"
 
 
+def test_restart_stops_then_starts_the_background_gateway(tmp_path, monkeypatch):
+    runtime = GatewayRuntime(paths=_paths(tmp_path), platform_name="Linux")
+    status = GatewayStatus(
+        running=True,
+        pid=12345,
+        state_path=runtime.paths.state_path,
+        log_path=runtime.paths.log_path,
+        launch_mode="background",
+    )
+    monkeypatch.setattr(runtime, "status", lambda **_kwargs: status)
+
+    def stop(*, timeout_s: int):
+        assert timeout_s == 20
+        return SimpleNamespace(ok=True, message="gateway_stopped", status=status)
+
+    monkeypatch.setattr(runtime, "_stop", stop)
+    monkeypatch.setattr(
+        runtime,
+        "_start_background",
+        lambda _options: RuntimeResult(True, "gateway_started_background", status),
+    )
+
+    result = runtime.restart(GatewayStartOptions(port=18790))
+
+    assert result.ok is True
+
+
 def test_last_interactive_client_stops_an_on_demand_gateway(tmp_path, monkeypatch):
     runtime = GatewayRuntime(paths=_paths(tmp_path), platform_name="Linux")
     monkeypatch.setattr(runtime, "_process_identity", lambda pid: pid)

tests/session/test_recovery.py

@@ -0,0 +1,773 @@
+from __future__ import annotations
+
+import asyncio
+from pathlib import Path
+
+import pytest
+
+from nanobot.bus.events import InboundMessage
+from nanobot.bus.outbound_events import RecoveryStateEvent, SessionUpdatedEvent
+from nanobot.bus.queue import MessageBus
+from nanobot.session.manager import Session, SessionManager
+from nanobot.session.recovery import (
+    PENDING_FOLLOWUPS_KEY,
+    PENDING_USER_TURN_KEY,
+    RECOVERY_METADATA_KEY,
+    RUNTIME_CHECKPOINT_KEY,
+    RecoveryActionError,
+    RecoveryCoordinator,
+    acknowledge_pending_followups,
+    pending_followups,
+    record_pending_followup,
+)
+from nanobot.webui import session_list_index, transcript
+
+
+def _persist(manager: SessionManager, session: Session) -> None:
+    session.metadata["webui"] = True
+    manager.save(session)
+
+
+def _coordinator(workspace: Path) -> tuple[RecoveryCoordinator, MessageBus, SessionManager]:
+    bus = MessageBus()
+    sessions = SessionManager(workspace)
+    return RecoveryCoordinator(sessions, bus), bus, sessions
+
+
+@pytest.mark.asyncio
+async def test_restart_before_model_call_waits_for_confirmation(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "finish this"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    restored = restarted.get_or_create("websocket:chat")
+    assert restored.metadata[PENDING_USER_TURN_KEY] is True
+    assert restored.metadata[RECOVERY_METADATA_KEY]["status"] == "awaiting_user"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "restart_requires_confirmation"
+
+
+@pytest.mark.asyncio
+async def test_stale_incomplete_transcript_waits_for_confirmation(tmp_path: Path, monkeypatch) -> None:
+    """A materialized shutdown must not reappear as an endless Working state."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    _persist(sessions, session)
+    monkeypatch.setattr(
+        "nanobot.webui.transcript.has_unfinished_transcript_tail",
+        lambda _key: True,
+    )
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "interrupted_without_checkpoint"
+    event = bus.outbound.get_nowait().event
+    assert isinstance(event, RecoveryStateEvent)
+    assert event.status == "awaiting_user"
+
+
+@pytest.mark.asyncio
+async def test_materialized_interruption_can_continue_from_saved_context(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Older shutdowns may have cleared the checkpoint after saving partial history."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.extend(
+        [
+            {"role": "user", "content": "research this"},
+            {"role": "assistant", "content": "I will check."},
+            {"role": "tool", "tool_call_id": "search-1", "content": "saved result"},
+        ]
+    )
+    _persist(sessions, session)
+    monkeypatch.setattr(
+        "nanobot.webui.transcript.has_unfinished_transcript_tail",
+        lambda _key: True,
+    )
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "interrupted_with_saved_context"
+    assert "can_continue" not in state
+    event = bus.outbound.get_nowait().event
+    assert isinstance(event, RecoveryStateEvent)
+    assert event.can_continue is None
+
+    await coordinator.handle_action(
+        "continue",
+        {"chat_id": "chat", "recovery_id": state["recovery_id"]},
+    )
+
+    continuation = bus.inbound.get_nowait()
+    assert continuation.session_key_override == "websocket:chat"
+
+
+@pytest.mark.asyncio
+async def test_transcript_only_interruption_is_discovered_without_materializing_completed_history(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    webui_dir = tmp_path / "webui"
+    webui_dir.mkdir()
+    monkeypatch.setattr(session_list_index, "get_webui_dir", lambda: webui_dir)
+    monkeypatch.setattr(transcript, "get_webui_dir", lambda: webui_dir)
+    unfinished_key = "websocket:unfinished"
+    completed_key = "websocket:completed"
+    (webui_dir / f"{SessionManager.safe_key(unfinished_key)}.jsonl").write_text(
+        '{"event":"user","chat_id":"unfinished","text":"keep going"}\n'
+        '{"event":"message","chat_id":"unfinished","kind":"progress","text":"Working"}\n',
+        encoding="utf-8",
+    )
+    (webui_dir / f"{SessionManager.safe_key(completed_key)}.jsonl").write_text(
+        '{"event":"user","chat_id":"completed","text":"done"}\n'
+        '{"event":"message","chat_id":"completed","text":"finished"}\n'
+        '{"event":"turn_end","chat_id":"completed"}\n',
+        encoding="utf-8",
+    )
+    coordinator, bus, sessions = _coordinator(tmp_path / "workspace")
+
+    await coordinator.scan()
+
+    restored = sessions.get_or_create(unfinished_key)
+    assert restored.metadata[RECOVERY_METADATA_KEY]["status"] == "awaiting_user"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "interrupted_without_checkpoint"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["can_continue"] is False
+    assert sessions.read_session_metadata(completed_key) is None
+    event = bus.outbound.get_nowait().event
+    assert isinstance(event, RecoveryStateEvent)
+    assert event.status == "awaiting_user"
+    assert event.can_continue is False
+    assert bus.outbound.get_nowait().event.scope == "thread"
+    assert bus.outbound.empty()
+
+    with pytest.raises(RecoveryActionError, match="context is unavailable"):
+        await coordinator.handle_action(
+            "continue",
+            {"chat_id": "unfinished", "recovery_id": event.recovery_id},
+        )
+
+
+@pytest.mark.asyncio
+async def test_scan_loads_only_sessions_that_need_webui_recovery(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    sessions = SessionManager(tmp_path)
+    for key in ("telegram:idle", "discord:pending", "websocket:idle"):
+        session = sessions.get_or_create(key)
+        if key == "discord:pending":
+            session.metadata[PENDING_USER_TURN_KEY] = True
+        _persist(sessions, session)
+    pending = sessions.get_or_create("websocket:pending")
+    pending.metadata[PENDING_USER_TURN_KEY] = True
+    _persist(sessions, pending)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    loaded: list[str] = []
+    get_or_create = restarted.get_or_create
+
+    def tracked_get_or_create(key: str) -> Session:
+        loaded.append(key)
+        return get_or_create(key)
+
+    monkeypatch.setattr(restarted, "get_or_create", tracked_get_or_create)
+    monkeypatch.setattr(
+        "nanobot.webui.transcript.has_unfinished_transcript_tail",
+        lambda _key: False,
+    )
+
+    await coordinator.scan()
+
+    assert loaded == ["websocket:pending"]
+
+
+@pytest.mark.asyncio
+async def test_live_turn_followup_survives_restart_until_it_is_committed(tmp_path: Path) -> None:
+    """A message injected mid-turn is not lost between checkpoints."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    _persist(sessions, session)
+    followup_id = record_pending_followup(
+        session,
+        InboundMessage(
+            channel="websocket",
+            sender_id="user",
+            chat_id="chat",
+            content="also check the logs",
+            metadata={"webui": True},
+        ),
+    )
+    assert followup_id is not None
+    sessions.save(session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    queued = bus.inbound.get_nowait()
+    assert queued.content == "also check the logs"
+    assert queued.metadata["_recovery_followup_id"] == followup_id
+    restored = restarted.get_or_create("websocket:chat")
+    assert len(pending_followups(restored)) == 1
+
+    acknowledge_pending_followups(restored, [followup_id])
+    assert PENDING_FOLLOWUPS_KEY not in restored.metadata
+
+
+def test_followup_journal_keeps_every_uncommitted_message(tmp_path: Path) -> None:
+    """A live queue limit must never truncate durable WebUI follow-ups."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    followup_ids = [
+        record_pending_followup(
+            session,
+            InboundMessage(
+                channel="websocket",
+                sender_id="user",
+                chat_id="chat",
+                content=f"follow-up-{index}",
+                metadata={"webui": True},
+            ),
+        )
+        for index in range(21)
+    ]
+
+    assert all(followup_ids)
+    sessions.save(session)
+    restarted = SessionManager(tmp_path)
+    restored = restarted.get_or_create("websocket:chat")
+    assert [message.content for message in pending_followups(restored)] == [
+        f"follow-up-{index}" for index in range(21)
+    ]
+
+
+def test_requeued_followup_preserves_its_journal_id(tmp_path: Path) -> None:
+    """Routing a recovered follow-up into a live turn must remain idempotent."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    original_id = record_pending_followup(
+        session,
+        InboundMessage(
+            channel="websocket",
+            sender_id="user",
+            chat_id="chat",
+            content="also check the logs",
+            metadata={"webui": True},
+        ),
+    )
+    assert original_id is not None
+
+    recovered = pending_followups(session)[0]
+    assert record_pending_followup(session, recovered) == original_id
+    assert [record["id"] for record in session.metadata[PENDING_FOLLOWUPS_KEY]] == [
+        original_id
+    ]
+
+
+@pytest.mark.asyncio
+async def test_completed_tools_wait_for_confirmation_after_restart(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "inspect"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "tools_completed",
+        "assistant_message": {
+            "role": "assistant",
+            "content": "",
+            "tool_calls": [{"id": "call-1", "function": {"name": "read_file"}}],
+        },
+        "completed_tool_results": [
+            {
+                "role": "tool",
+                "tool_call_id": "call-1",
+                "name": "read_file",
+                "content": "saved result",
+            }
+        ],
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    restored = restarted.get_or_create("websocket:chat")
+    assert restored.messages[-1]["content"] == "saved result"
+    assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+    assert restored.metadata[RECOVERY_METADATA_KEY]["status"] == "awaiting_user"
+
+
+@pytest.mark.asyncio
+async def test_uncertain_tool_is_never_replayed(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "send it"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "awaiting_tools",
+        "assistant_message": {
+            "role": "assistant",
+            "content": "",
+            "tool_calls": [{"id": "call-1", "function": {"name": "send_email"}}],
+        },
+        "completed_tool_results": [],
+        "pending_tool_calls": [
+            {"id": "call-1", "function": {"name": "send_email"}}
+        ],
+    }
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    restored = restarted.get_or_create("websocket:chat")
+    assert restored.metadata[RECOVERY_METADATA_KEY]["status"] == "awaiting_user"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "tool_state_unknown"
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+    event = bus.outbound.get_nowait().event
+    assert isinstance(event, RecoveryStateEvent)
+    assert event.status == "awaiting_user"
+
+
+@pytest.mark.asyncio
+async def test_unknown_checkpoint_waits_for_confirmation(tmp_path: Path) -> None:
+    """Malformed or newer checkpoint phases fail closed pending confirmation."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "deploy it"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {"phase": "future_phase"}
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    restored = restarted.get_or_create("websocket:chat")
+    assert restored.metadata[RECOVERY_METADATA_KEY]["status"] == "awaiting_user"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "checkpoint_unknown"
+    assert restored.metadata[RECOVERY_METADATA_KEY]["can_continue"] is False
+    assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+    assert PENDING_USER_TURN_KEY not in restored.metadata
+    assert [message["role"] for message in restored.messages] == ["user", "assistant"]
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+
+    with pytest.raises(RecoveryActionError, match="context is unavailable"):
+        await coordinator.handle_action(
+            "continue",
+            {
+                "chat_id": "chat",
+                "recovery_id": restored.metadata[RECOVERY_METADATA_KEY]["recovery_id"],
+            },
+        )
+
+    dismissed = await coordinator.handle_action(
+        "dismiss",
+        {
+            "chat_id": "chat",
+            "recovery_id": restored.metadata[RECOVERY_METADATA_KEY]["recovery_id"],
+        },
+    )
+    assert dismissed["status"] == "recovered"
+
+
+@pytest.mark.asyncio
+async def test_malformed_checkpoint_can_always_be_dismissed(tmp_path: Path) -> None:
+    """Corrupt private state must not trap the user in a failed recovery notice."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "deploy it"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "future_phase",
+        "assistant_message": "invalid",
+        "completed_tool_results": 3,
+        "pending_tool_calls": [{"id": "call-1", "function": "invalid"}],
+    }
+    _persist(sessions, session)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+    restored = restarted.get_or_create("websocket:chat")
+    state = restored.metadata[RECOVERY_METADATA_KEY]
+
+    result = await coordinator.handle_action(
+        "dismiss",
+        {"chat_id": "chat", "recovery_id": state["recovery_id"]},
+    )
+
+    assert result["status"] == "recovered"
+    assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+
+
+@pytest.mark.asyncio
+async def test_known_but_malformed_checkpoint_cannot_continue(tmp_path: Path) -> None:
+    """A known phase does not make corrupt tool state safe to resume."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "send it"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "tools_completed",
+        "assistant_message": {"role": "assistant", "content": "working"},
+        "completed_tool_results": "missing durable results",
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+    restored = restarted.get_or_create("websocket:chat")
+    state = restored.metadata[RECOVERY_METADATA_KEY]
+
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "checkpoint_invalid"
+    assert state["can_continue"] is False
+    with pytest.raises(RecoveryActionError, match="context is unavailable"):
+        await coordinator.handle_action(
+            "continue",
+            {"chat_id": "chat", "recovery_id": state["recovery_id"]},
+        )
+
+
+@pytest.mark.asyncio
+async def test_malformed_final_response_is_not_reported_as_restored(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "answer"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "final_response",
+        "assistant_message": "not an answer row",
+        "completed_tool_results": [],
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "checkpoint_invalid"
+    assert state["can_continue"] is False
+    restored = restarted.get_or_create("websocket:chat")
+    assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+    assert PENDING_USER_TURN_KEY not in restored.metadata
+    assert [message["role"] for message in restored.messages] == ["user", "assistant"]
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+    assert all("tool_calls" not in message for message in restored.messages)
+
+
+@pytest.mark.asyncio
+async def test_checkpoint_with_missing_tool_result_cannot_continue(tmp_path: Path) -> None:
+    """Never resume when persisted results do not cover every requested tool."""
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "send both"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "tools_completed",
+        "assistant_message": {
+            "role": "assistant",
+            "content": "",
+            "tool_calls": [
+                {"id": "call-1", "function": {"name": "send_email"}},
+                {"id": "call-2", "function": {"name": "send_email"}},
+            ],
+        },
+        "completed_tool_results": [
+            {
+                "role": "tool",
+                "tool_call_id": "call-1",
+                "name": "send_email",
+                "content": "sent",
+            }
+        ],
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    restored = restarted.get_or_create("websocket:chat")
+    state = restored.metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "checkpoint_invalid"
+    assert state["can_continue"] is False
+    assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+    assert PENDING_USER_TURN_KEY not in restored.metadata
+    assert [message["role"] for message in restored.messages] == ["user", "assistant"]
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+    assert all("tool_calls" not in message for message in restored.messages)
+
+
+@pytest.mark.asyncio
+async def test_empty_final_response_is_not_reported_as_restored(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "answer"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "final_response",
+        "assistant_message": {"role": "assistant", "content": ""},
+        "completed_tool_results": [],
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, _, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "awaiting_user"
+    assert state["reason"] == "checkpoint_invalid"
+    assert state["can_continue"] is False
+
+
+@pytest.mark.asyncio
+async def test_final_answer_is_restored_without_model_call(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "answer"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "final_response",
+        "assistant_message": {"role": "assistant", "content": "already finished"},
+        "completed_tool_results": [],
+        "pending_tool_calls": [],
+    }
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    restored = restarted.get_or_create("websocket:chat")
+    assert restored.messages[-1]["content"] == "already finished"
+    first = bus.outbound.get_nowait().event
+    second = bus.outbound.get_nowait().event
+    assert isinstance(first, RecoveryStateEvent) and first.status == "recovered"
+    assert isinstance(second, SessionUpdatedEvent)
+
+
+@pytest.mark.asyncio
+async def test_explicit_recovery_continue_queues_once(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "continue"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+    assert bus.inbound.empty()
+
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    result = await coordinator.handle_action(
+        "continue",
+        {"chat_id": "chat", "recovery_id": state["recovery_id"]},
+    )
+    assert result["status"] == "resuming"
+    assert bus.inbound.get_nowait().metadata["_webui_recovery_id"] == state["recovery_id"]
+
+
+@pytest.mark.asyncio
+async def test_new_user_message_supersedes_waiting_recovery(tmp_path: Path) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.append({"role": "user", "content": "old request"})
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    _persist(sessions, session)
+    await coordinator.scan()
+
+    newer = InboundMessage(
+        channel="websocket",
+        sender_id="user",
+        chat_id="chat",
+        content="new request",
+    )
+    assert await coordinator.admit(newer) is True
+    restored = sessions.get_or_create("websocket:chat")
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+    assert sum(
+        message.get("_recovery_interrupted") is True
+        for message in restored.messages
+    ) == 1
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "superseded"
+
+
+@pytest.mark.asyncio
+async def test_new_user_message_cancels_active_recovery_task(tmp_path: Path) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "resuming",
+        "recovery_id": "active",
+        "attempts": 1,
+    }
+    _persist(sessions, session)
+
+    started = asyncio.Event()
+
+    async def _active_recovery() -> None:
+        started.set()
+        await asyncio.Event().wait()
+
+    task = asyncio.create_task(_active_recovery())
+    await started.wait()
+    coordinator.register_recovery_task("websocket:chat", task)
+
+    newer = InboundMessage(
+        channel="websocket",
+        sender_id="user",
+        chat_id="chat",
+        content="new request",
+    )
+    assert await coordinator.admit(newer) is True
+    assert task.cancelled()
+    restored = sessions.get_or_create("websocket:chat")
+    assert restored.metadata[RECOVERY_METADATA_KEY]["reason"] == "superseded"
+    assert restored.messages[-1]["_recovery_interrupted"] is True
+    first = bus.outbound.get_nowait().event
+    second = bus.outbound.get_nowait().event
+    assert isinstance(first, RecoveryStateEvent)
+    assert isinstance(second, SessionUpdatedEvent)
+    assert bus.outbound.empty()
+
+
+@pytest.mark.asyncio
+async def test_recovery_action_rejects_stale_page_and_continues_current_state(
+    tmp_path: Path,
+) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "awaiting_user",
+        "recovery_id": "current",
+        "attempts": 0,
+    }
+    _persist(sessions, session)
+
+    with pytest.raises(RecoveryActionError, match="stale"):
+        await coordinator.handle_action(
+            "continue",
+            {"chat_id": "chat", "recovery_id": "old"},
+        )
+
+    result = await coordinator.handle_action(
+        "continue",
+        {"chat_id": "chat", "recovery_id": "current"},
+    )
+    assert result["status"] == "resuming"
+    assert bus.inbound.get_nowait().metadata["_webui_recovery_id"] == "current"
+
+
+@pytest.mark.asyncio
+async def test_persisted_completion_wins_over_stale_resuming_marker(tmp_path: Path) -> None:
+    sessions = SessionManager(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.messages.extend(
+        [
+            {"role": "user", "content": "work"},
+            {"role": "assistant", "content": "done"},
+        ]
+    )
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "resuming",
+        "recovery_id": "recovery",
+        "attempts": 1,
+        "resume_message_count": 1,
+    }
+    _persist(sessions, session)
+
+    coordinator, bus, restarted = _coordinator(tmp_path)
+    await coordinator.scan()
+
+    assert bus.inbound.empty()
+    state = restarted.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "recovered"
+    assert state["reason"] == "committed"
+
+
+@pytest.mark.asyncio
+async def test_dismiss_does_not_queue_work(tmp_path: Path) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "awaiting_user",
+        "recovery_id": "current",
+        "attempts": 0,
+    }
+    _persist(sessions, session)
+
+    result = await coordinator.handle_action(
+        "dismiss",
+        {"chat_id": "chat", "recovery_id": "current"},
+    )
+
+    assert result["status"] == "recovered"
+    assert bus.inbound.empty()
+
+
+@pytest.mark.asyncio
+async def test_scan_failure_is_visible_instead_of_aborting_other_sessions(
+    tmp_path: Path,
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    _persist(sessions, session)
+
+    async def fail(*_args: object, **_kwargs: object) -> None:
+        raise RuntimeError("boom")
+
+    monkeypatch.setattr(RecoveryCoordinator, "_recover_session", fail)
+    await coordinator.scan()
+
+    state = sessions.get_or_create("websocket:chat").metadata[RECOVERY_METADATA_KEY]
+    assert state["status"] == "failed"
+    assert state["can_continue"] is False
+    assert isinstance(bus.outbound.get_nowait().event, RecoveryStateEvent)
+
+    with pytest.raises(RecoveryActionError, match="context is unavailable"):
+        await coordinator.handle_action(
+            "continue",
+            {"chat_id": "chat", "recovery_id": state["recovery_id"]},
+        )
+
+
+@pytest.mark.asyncio
+async def test_bus_remains_quiet_after_recovered_state(tmp_path: Path) -> None:
+    coordinator, bus, sessions = _coordinator(tmp_path)
+    session = sessions.get_or_create("websocket:chat")
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "recovered",
+        "recovery_id": "done",
+        "attempts": 1,
+    }
+    _persist(sessions, session)
+
+    await coordinator.scan()
+
+    await asyncio.sleep(0)
+    assert bus.inbound.empty()
+    assert bus.outbound.empty()

tests/session/test_session_store.py

@@ -1,6 +1,7 @@
 from unittest.mock import MagicMock
 
 import nanobot.session as session_api
+from nanobot.providers.base import ProviderConversationState
 from nanobot.session import Session, SessionManager
 from nanobot.session.manager import SessionStore
 from nanobot.session.model_selection import SESSION_MODEL_PRESET_METADATA_KEY
@@ -123,3 +124,93 @@ def test_manager_preserves_full_session_before_store_save(tmp_path) -> None:
     assert session.messages[0]["content"] == "0"
     assert session.messages[-1]["content"] == "2000"
     store.save.assert_called_once_with(session, fsync=False)
+
+
+def test_runtime_checkpoint_does_not_rewrite_long_session(tmp_path) -> None:
+    manager = SessionManager(tmp_path)
+    session = manager.get_or_create("websocket:long")
+    for index in range(256):
+        session.add_message("user", f"{index}:" + "x" * 4096)
+    manager.save(session)
+
+    main_path = manager._get_session_path(session.key)
+    main_before = main_path.read_bytes()
+    stat_before = main_path.stat()
+    session.metadata["runtime_checkpoint"] = {
+        "phase": "tools_completed",
+        "assistant_message": {"role": "assistant", "content": "working"},
+        "completed_tool_results": [],
+        "pending_tool_calls": [],
+    }
+    session.provider_state = ProviderConversationState(
+        kind="openai_responses",
+        provider="openai:test",
+        model="test-model",
+        version=1,
+        payload={"response_id": "private-response"},
+    )
+
+    manager.save_runtime_checkpoint(session)
+
+    checkpoint_path = manager._get_runtime_checkpoint_path(session.key)
+    assert main_path.read_bytes() == main_before
+    assert main_path.stat().st_ino == stat_before.st_ino
+    assert main_path.stat().st_mtime_ns == stat_before.st_mtime_ns
+    assert checkpoint_path.stat().st_size < len(main_before) // 100
+
+    restored = SessionManager(tmp_path).get_or_create(session.key)
+    assert restored.metadata["runtime_checkpoint"]["phase"] == "tools_completed"
+    assert restored.provider_state is not None
+    assert restored.provider_state.payload == {"response_id": "private-response"}
+
+
+def test_completed_session_supersedes_stale_checkpoint(tmp_path) -> None:
+    manager = SessionManager(tmp_path)
+    session = manager.get_or_create("websocket:completed")
+    session.add_message("user", "question")
+    manager.save(session)
+    session.metadata["runtime_checkpoint"] = {"phase": "awaiting_tools"}
+    manager.save_runtime_checkpoint(session)
+    checkpoint_path = manager._get_runtime_checkpoint_path(session.key)
+    stale_checkpoint = checkpoint_path.read_bytes()
+
+    session.metadata.pop("runtime_checkpoint")
+    session.add_message("assistant", "answer")
+    manager.save(session)
+    assert not checkpoint_path.exists()
+
+    # Emulate a process dying after the main record was committed but before an
+    # obsolete sidecar could be removed. The base fingerprint keeps it stale.
+    checkpoint_path.write_bytes(stale_checkpoint)
+    restored = SessionManager(tmp_path).get_or_create(session.key)
+    assert "runtime_checkpoint" not in restored.metadata
+    assert restored.messages[-1]["content"] == "answer"
+    assert not checkpoint_path.exists()
+
+
+def test_delete_session_removes_runtime_checkpoint(tmp_path) -> None:
+    manager = SessionManager(tmp_path)
+    session = manager.get_or_create("websocket:delete")
+    session.add_message("user", "question")
+    manager.save(session)
+    session.metadata["runtime_checkpoint"] = {"phase": "awaiting_tools"}
+    manager.save_runtime_checkpoint(session)
+    checkpoint_path = manager._get_runtime_checkpoint_path(session.key)
+    assert checkpoint_path.exists()
+
+    assert manager.delete_session(session.key) is True
+    assert not checkpoint_path.exists()
+
+
+def test_invalid_runtime_checkpoint_is_discarded(tmp_path) -> None:
+    manager = SessionManager(tmp_path)
+    session = manager.get_or_create("websocket:invalid-checkpoint")
+    session.add_message("user", "question")
+    manager.save(session)
+    checkpoint_path = manager._get_runtime_checkpoint_path(session.key)
+    checkpoint_path.write_text("{truncated", encoding="utf-8")
+
+    restored = SessionManager(tmp_path).get_or_create(session.key)
+
+    assert "runtime_checkpoint" not in restored.metadata
+    assert not checkpoint_path.exists()

tests/utils/test_webui_transcript.py

@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from pathlib import Path
+
 import nanobot.webui.transcript as transcript_module
 from nanobot.session.history_visibility import HIDDEN_HISTORY_META
 from nanobot.webui.transcript import (
@@ -554,6 +556,22 @@ def test_thread_response_marks_unfinished_tool_tail_pending(tmp_path, monkeypatc
     assert out["completed_turn_ids"] == []
 
 
+def test_recovery_tail_check_reads_only_the_active_transcript(tmp_path, monkeypatch) -> None:
+    monkeypatch.setattr("nanobot.config.paths.get_data_dir", lambda: tmp_path)
+    key = "websocket:recovery-tail"
+    active_path = transcript_module.webui_transcript_path(key)
+    reads: list[Path] = []
+
+    def read(path: Path) -> list[dict[str, object]]:
+        reads.append(path)
+        return [{"event": "message", "kind": "progress", "text": "running"}]
+
+    monkeypatch.setattr(transcript_module, "_read_transcript_file", read)
+
+    assert transcript_module.has_unfinished_transcript_tail(key) is True
+    assert reads == [active_path]
+
+
 def test_thread_response_reports_active_registry_without_transcript(
     tmp_path,
     monkeypatch,

tests/webui/test_gateway_webui_smoke.py

@@ -15,6 +15,9 @@ import httpx
 import pytest
 import websockets
 
+from nanobot.session.manager import SessionManager
+from nanobot.session.recovery import PENDING_USER_TURN_KEY, RUNTIME_CHECKPOINT_KEY
+
 _BOOTSTRAP_SECRET = "smoke-secret"
 
 
@@ -206,3 +209,84 @@ async def test_gateway_webui_bootstrap_message_and_thread_hydration(tmp_path: Pa
         assert any("shell-ok" in text for text in contents)
     finally:
         _stop_gateway(process)
+
+
+def test_gateway_restart_restores_a_completed_answer_without_replaying_model(
+    tmp_path: Path,
+) -> None:
+    """Exercise recovery through two real gateway processes and durable files."""
+    ws_port = _free_port()
+    gateway_port = _free_port()
+    workspace = tmp_path / "workspace"
+    workspace.mkdir()
+    config_path = tmp_path / "config.json"
+    first_log = tmp_path / "gateway-first.log"
+    second_log = tmp_path / "gateway-second.log"
+    _write_smoke_config(
+        config_path,
+        workspace=workspace,
+        ws_port=ws_port,
+        gateway_port=gateway_port,
+    )
+    base_url = f"http://127.0.0.1:{ws_port}"
+
+    first = _start_gateway(config_path, first_log)
+    try:
+        _wait_for_bootstrap(base_url, first, first_log)
+    finally:
+        _stop_gateway(first)
+
+    sessions_root = tmp_path / "sessions"
+    sessions = SessionManager(workspace, sessions_root=sessions_root)
+    session = sessions.get_or_create("websocket:recovery-smoke")
+    session.messages.append({"role": "user", "content": "recover this answer"})
+    session.metadata["webui"] = True
+    session.metadata[PENDING_USER_TURN_KEY] = True
+    session.metadata[RUNTIME_CHECKPOINT_KEY] = {
+        "phase": "final_response",
+        "assistant_message": {
+            "role": "assistant",
+            "content": "restored without another model request",
+        },
+        "completed_tool_results": [],
+        "pending_tool_calls": [],
+    }
+    sessions.save(session, fsync=True)
+
+    second = _start_gateway(config_path, second_log)
+    try:
+        bootstrap = _wait_for_bootstrap(base_url, second, second_log)
+        deadline = time.monotonic() + 20
+        restored = None
+        while time.monotonic() < deadline:
+            restored = SessionManager(
+                workspace,
+                sessions_root=sessions_root,
+            ).get_or_create("websocket:recovery-smoke")
+            if any(
+                message.get("content") == "restored without another model request"
+                for message in restored.messages
+            ):
+                break
+            time.sleep(0.1)
+        else:
+            logs = second_log.read_text(encoding="utf-8", errors="replace")
+            raise AssertionError(f"answer was not recovered after restart\n{logs}")
+
+        assert restored is not None
+        assert PENDING_USER_TURN_KEY not in restored.metadata
+        assert RUNTIME_CHECKPOINT_KEY not in restored.metadata
+        assert restored.metadata["webui_recovery"]["reason"] == "answer_restored"
+
+        async def assert_attach_state() -> None:
+            ws_url = f'{bootstrap["ws_url"]}?token={bootstrap["token"]}&client_id=recovery-smoke'
+            async with websockets.connect(ws_url) as ws:
+                await _recv_until(ws, "ready")
+                await ws.send(json.dumps({"type": "attach", "chat_id": "recovery-smoke"}))
+                attached = await _recv_until(ws, "attached")
+                assert attached["recovery_state"]["status"] == "recovered"
+                assert attached["recovery_state"]["reason"] == "answer_restored"
+
+        asyncio.run(assert_attach_state())
+    finally:
+        _stop_gateway(second)

tests/webui/test_session_list_index.py

@@ -18,6 +18,7 @@ from nanobot.session.automation_turns import AUTOMATION_HISTORY_META
 from nanobot.session.history_visibility import HIDDEN_HISTORY_META
 from nanobot.session.manager import SessionManager
 from nanobot.session.model_selection import SESSION_MODEL_PRESET_METADATA_KEY
+from nanobot.session.recovery import RECOVERY_METADATA_KEY
 
 
 @pytest.fixture(autouse=True)
@@ -66,6 +67,30 @@ def test_webui_session_list_refreshes_after_model_preset_rename(tmp_path: Path)
     assert list_webui_sessions(manager)[0]["model_preset"] == "Codex"
 
 
+def test_webui_session_list_surfaces_pending_recovery_state(tmp_path: Path) -> None:
+    manager = SessionManager(tmp_path)
+    session = manager.get_or_create("websocket:needs-attention")
+    session.add_message("user", "the interrupted task")
+    session.metadata[RECOVERY_METADATA_KEY] = {
+        "status": "awaiting_user",
+        "recovery_id": "recovery-123",
+        "reason": "uncertain_tool_state",
+        "attempts": 1,
+        # Private checkpoint details must never leak into the sidebar index.
+        "checkpoint": {"tool_args": "secret"},
+    }
+    manager.save(session)
+
+    row = list_webui_sessions(manager)[0]
+
+    assert row["recovery_state"] == {
+        "status": "awaiting_user",
+        "recovery_id": "recovery-123",
+        "reason": "uncertain_tool_state",
+        "attempts": 1,
+    }
+
+
 def test_webui_session_index_uses_unique_temp_file(tmp_path: Path) -> None:
     manager = SessionManager(tmp_path)
     session = manager.get_or_create("websocket:unique-index-temp")

tui/src/app.test.ts

@@ -7,7 +7,12 @@ import {
 } from "@opentui/core/testing"
 
 import { NanobotTui, sessionExitMessage, type AppOptions } from "./app"
-import type { MessageOptions, SlashCommand, WorkspaceScopePayload } from "./protocol"
+import type {
+  MessageOptions,
+  RecoveryState,
+  SlashCommand,
+  WorkspaceScopePayload,
+} from "./protocol"
 import type { HostAgentState, HostMetadata, TuiHost } from "./host"
 
 const options: AppOptions = {
@@ -91,6 +96,13 @@ function client(
     setWorkspaceScope(scope: WorkspaceScopePayload) {
       scopes.push(scope)
     },
+    updateRecovery(
+      _action: "continue" | "dismiss",
+      _chatId: string,
+      recoveryId: string,
+    ): Promise<RecoveryState> {
+      return Promise.resolve({ status: "recovered" as const, recovery_id: recoveryId })
+    },
   }
 }
 
@@ -555,6 +567,97 @@ describe("NanobotTui layout", () => {
     }
   })
 
+  test("switches away from a running session without losing its queued follow-ups", async () => {
+    setup = await createRenderer({ width: 80, height: 24, screenMode: "alternate-screen" })
+    const original = globalThis.fetch
+    globalThis.fetch = ((input: string | URL | Request) => {
+      const url = String(input)
+      if (url.endsWith("/api/sessions")) {
+        return Promise.resolve(new Response(JSON.stringify({
+          sessions: [
+            { key: "websocket:chat", title: "Running chat", run_started_at: 1_700_000_000 },
+            { key: "websocket:other", title: "Other chat" },
+          ],
+        })))
+      }
+      if (url.endsWith("/api/webui/sidebar-state")) {
+        return Promise.resolve(new Response(JSON.stringify({})))
+      }
+      return Promise.resolve(new Response(JSON.stringify({
+        messages: [],
+        page: { has_more_before: false },
+      })))
+    }) as typeof fetch
+    const sent: string[] = []
+    const attached: string[] = []
+    let activeChatId = "chat"
+    const base = client(sent, attached)
+    const transport = {
+      ...base,
+      get activeChatId() { return activeChatId },
+      attach(chatId: string) {
+        attached.push(chatId)
+        activeChatId = chatId
+      },
+    }
+    const app = NanobotTui.mount(
+      setup.renderer,
+      { ...options, apiUrl: "http://nanobot.test", apiToken: "secret" },
+      transport,
+      new MockTreeSitterClient({ autoResolveTimeout: 0 }),
+    )
+    const ui = app as unknown as {
+      ready: boolean
+      activeTurn: boolean
+      composer: TextareaRenderable
+      sessionMenu: { visible: boolean }
+      queuePreview: { root: { visible: boolean } }
+      status: { plainText: string }
+    }
+
+    try {
+      app.accept({ event: "attached", chat_id: "chat" })
+      await waitUntil(() => ui.ready)
+      app.accept({ event: "goal_status", chat_id: "chat", status: "running", turn_id: "turn" })
+      ui.composer.setText("follow up in chat")
+      setup.mockInput.pressTab()
+      await waitUntil(() => ui.composer.plainText === "")
+      expect(ui.queuePreview.root.visible).toBe(true)
+
+      ui.composer.setText("/sessions")
+      ui.composer.submit()
+      await waitUntil(() => ui.sessionMenu.visible)
+      await Bun.sleep(120)
+      expect(ui.status.plainText).toContain("2 sessions")
+
+      ui.composer.setText("other")
+      ui.composer.submit()
+      await waitUntil(() => attached.at(-1) === "other")
+      app.accept({ event: "attached", chat_id: "other" })
+      await waitUntil(() => ui.ready)
+      expect(ui.activeTurn).toBe(false)
+      expect(ui.queuePreview.root.visible).toBe(false)
+
+      ui.composer.setText("/sessions")
+      ui.composer.submit()
+      await waitUntil(() => ui.sessionMenu.visible)
+      ui.composer.setText("running")
+      ui.composer.submit()
+      await waitUntil(() => attached.at(-1) === "chat")
+      app.accept({ event: "attached", chat_id: "chat" })
+      app.accept({ event: "goal_status", chat_id: "chat", status: "running", turn_id: "turn" })
+      await waitUntil(() => ui.ready && ui.activeTurn)
+      expect(ui.queuePreview.root.visible).toBe(true)
+      expect(sent).toEqual([])
+
+      app.accept({ event: "turn_end", chat_id: "chat", turn_id: "turn" })
+      await waitUntil(() => sent.length === 1)
+      expect(sent).toEqual(["follow up in chat"])
+    } finally {
+      globalThis.fetch = original
+    }
+  })
+
   test("refreshes expired API credentials before opening sessions", async () => {
     setup = await createRenderer({ width: 80, height: 24, screenMode: "alternate-screen" })
     const original = globalThis.fetch
@@ -903,6 +1006,127 @@ describe("NanobotTui layout", () => {
     }
   })
 
+  test("offers clickable recovery actions without letting a late response revive stale state", async () => {
+    setup = await createRenderer({ width: 96, height: 24, screenMode: "alternate-screen" })
+    const calls: Array<{ action: string; chatId: string; recoveryId: string }> = []
+    let deferredResolve: ((state: RecoveryState) => void) | undefined
+    const recoveryClient = client()
+    recoveryClient.updateRecovery = (action, chatId, recoveryId) => {
+      calls.push({ action, chatId, recoveryId })
+      if (recoveryId === "recovery-1") {
+        return Promise.resolve({ status: "resuming", recovery_id: recoveryId })
+      }
+      if (action === "dismiss") {
+        return Promise.resolve({ status: "recovered", recovery_id: recoveryId })
+      }
+      return new Promise((resolve) => { deferredResolve = resolve })
+    }
+    const app = NanobotTui.mount(
+      setup.renderer,
+      options,
+      recoveryClient,
+      new MockTreeSitterClient({ autoResolveTimeout: 0 }),
+    )
+    app.accept({
+      event: "attached",
+      chat_id: "chat",
+      recovery_state: {
+        status: "awaiting_user",
+        recovery_id: "recovery-1",
+        reason: "tool execution interrupted",
+      },
+    })
+    const ui = app as unknown as {
+      activeTurn: boolean
+      composer: TextareaRenderable
+      recoveryNotice: {
+        visible: boolean
+        dismiss: TextRenderable
+        resume: TextRenderable
+      }
+      status: TextRenderable
+    }
+
+    await waitUntil(() => (app as unknown as { ready: boolean }).ready)
+    await setup.renderOnce()
+    expect(setup.captureCharFrame()).toContain("⚠ Task interrupted")
+    expect(setup.captureCharFrame()).toContain("Tools will not replay automatically")
+    expect(ui.status.plainText).toContain("continue or dismiss")
+    expect(ui.activeTurn).toBe(false)
+    expect(ui.composer.focused).toBe(true)
+
+    await setup.mockMouse.click(ui.recoveryNotice.resume.x + 1, ui.recoveryNotice.resume.y)
+    await waitUntil(() => calls.length === 1 && ui.activeTurn)
+    expect(calls[0]).toEqual({
+      action: "continue",
+      chatId: "chat",
+      recoveryId: "recovery-1",
+    })
+    expect(ui.recoveryNotice.visible).toBe(false)
+    expect(ui.status.plainText).toContain("Continuing")
+
+    app.accept({
+      event: "recovery_state",
+      chat_id: "chat",
+      status: "awaiting_user",
+      recovery_id: "recovery-2",
+    })
+    await setup.renderOnce()
+    await setup.mockMouse.click(ui.recoveryNotice.resume.x + 1, ui.recoveryNotice.resume.y)
+    await waitUntil(() => calls.length === 2)
+    app.accept({
+      event: "recovery_state",
+      chat_id: "chat",
+      status: "recovered",
+      recovery_id: "recovery-2",
+    })
+    deferredResolve?.({ status: "resuming", recovery_id: "recovery-2" })
+    await Bun.sleep(1)
+
+    expect(ui.recoveryNotice.visible).toBe(false)
+    expect(ui.activeTurn).toBe(false)
+    expect(ui.composer.focused).toBe(true)
+
+    app.accept({
+      event: "recovery_state",
+      chat_id: "chat",
+      status: "awaiting_user",
+      recovery_id: "recovery-unavailable",
+      can_continue: false,
+    })
+    await setup.renderOnce()
+    const unavailableFrame = setup.captureCharFrame()
+    expect(unavailableFrame).toContain("can’t be resumed safely")
+    expect(unavailableFrame).not.toContain("Continue")
+    expect(ui.status.plainText).toContain("dismiss to start a new message")
+
+    app.accept({
+      event: "recovery_state",
+      chat_id: "chat",
+      status: "awaiting_user",
+      recovery_id: "recovery-3",
+    })
+    await setup.renderOnce()
+    await setup.mockMouse.click(ui.recoveryNotice.dismiss.x + 1, ui.recoveryNotice.dismiss.y)
+    await waitUntil(() => calls.length === 3 && !ui.recoveryNotice.visible)
+    expect(calls[2]).toEqual({
+      action: "dismiss",
+      chatId: "chat",
+      recoveryId: "recovery-3",
+    })
+
+    app.accept({
+      event: "recovery_state",
+      chat_id: "chat",
+      status: "awaiting_user",
+      recovery_id: "recovery-4",
+      can_continue: false,
+    })
+    await setup.renderOnce()
+    expect(ui.recoveryNotice.resume.visible).toBe(false)
+    expect(ui.recoveryNotice.dismiss.visible).toBe(true)
+  })
+
   test("preserves gateway slash lifecycle while local navigation stays in the same menu", async () => {
     setup = await createRenderer({ width: 80, height: 24, screenMode: "alternate-screen" })
     const sent: string[] = []

tui/src/app.ts

@@ -34,6 +34,7 @@ import {
   type InboundEvent,
   type MentionCandidate,
   type MessageOptions,
+  type RecoveryState,
   type SlashCommand,
   type SessionSummary,
   type TokenUsage,
@@ -70,6 +71,7 @@ import {
 } from "./mention-menu"
 import { PromptQueue, type QueuedPrompt } from "./prompt-queue"
 import { QueuePreview, type QueuePreviewTheme } from "./queue-preview"
+import { RecoveryNotice, type RecoveryNoticeTheme } from "./recovery-notice"
 import { RuntimeControls } from "./runtime-controls"
 import {
   contextualFooterHints,
@@ -107,6 +109,11 @@ interface ChatClient {
   newChat(scope?: WorkspaceScopePayload): void
   forkChat?(sourceChatId: string, beforeUserIndex: number, title?: string): void
   setWorkspaceScope(scope: WorkspaceScopePayload): void
+  updateRecovery(
+    action: "continue" | "dismiss",
+    chatId: string,
+    recoveryId: string,
+  ): Promise<RecoveryState>
 }
 
 interface Palette {
@@ -118,6 +125,7 @@ interface Palette {
   accent: string
   link: string
   success: string
+  warning: string
   error: string
   user: string
   userBackground: string
@@ -134,6 +142,7 @@ const DARK: Palette = {
   accent: "#EF8E30",
   link: "#60A5FA",
   success: "#5CC489",
+  warning: "#F5C451",
   error: "#F87171",
   user: "#EF8E30",
   // Codex-style turn anchor: 12% white over the reference dark background.
@@ -151,6 +160,7 @@ const LIGHT: Palette = {
   accent: "#B94D0B",
   link: "#1D4ED8",
   success: "#166534",
+  warning: "#A16207",
   error: "#B91C1C",
   user: "#B94D0B",
   // Codex-style turn anchor: 4% black over the reference light background.
@@ -164,6 +174,7 @@ const ACTIVE_COMPOSER_PLACEHOLDER = "Steer this turn…"
 const SHIMMER_PAUSE = 16
 const SHIMMER_BAND = 4
 const SHIMMER_INTERVAL_MS = 80
+const SESSION_REFRESH_INTERVAL_MS = 1_000
 const LOCAL_COMMANDS: TuiCommand[] = [
   {
     command: "/sessions",
@@ -252,6 +263,8 @@ function commandMenuTheme(palette: Palette): CommandMenuTheme {
     text: palette.text,
     muted: palette.muted,
     border: palette.border,
+    accent: palette.accent,
+    warning: palette.warning,
     selectedBackground: palette.userBackground,
   }
 }
@@ -295,6 +308,17 @@ function queuePreviewTheme(palette: Palette): QueuePreviewTheme {
   }
 }
 
+function recoveryNoticeTheme(palette: Palette): RecoveryNoticeTheme {
+  return {
+    text: palette.text,
+    muted: palette.muted,
+    border: palette.border,
+    accent: palette.accent,
+    warning: palette.warning,
+    error: palette.error,
+  }
+}
+
 function footerHintTheme(palette: Palette): FooterHintTheme {
   return {
     accent: palette.accent,
@@ -380,6 +404,7 @@ export class NanobotTui {
   private readonly contextPanel: ContextPanel
   private readonly diffViewer: DiffViewer
   private readonly queuePreview: QueuePreview
+  private readonly recoveryNotice: RecoveryNotice
   private readonly client: ChatClient
   private readonly shell: BoxRenderable
   private readonly title: BoxRenderable
@@ -390,7 +415,8 @@ export class NanobotTui {
   private readonly meta: TextRenderable
   private readonly host: TuiHost
   private readonly draft = new ComposerDraft()
-  private readonly promptQueue = new PromptQueue()
+  private readonly promptQueues = new Map<string, PromptQueue>()
+  private currentChatId = ""
   private palette: Palette
   private activeThemeMode: ThemeMode
   private backgroundKnown: boolean
@@ -436,6 +462,8 @@ export class NanobotTui {
   private quitting = false
   private sessionLoadId = 0
   private sessionLoading = false
+  private sessionRefreshPending = false
+  private sessionRefreshTimer: ReturnType<typeof setInterval> | null = null
   private readonly commandTurns = new Map<string, ResolvedSlashCommandLifecycle>()
   private readonly modelCommandTurns = new Set<string>()
   private readonly silentCommandTurns = new Set<string>()
@@ -444,6 +472,8 @@ export class NanobotTui {
   private currentTask = ""
   private currentAction = ""
   private hostBlocked = false
+  private recoveryState: RecoveryState | null = null
+  private recoveryPending = false
   private hostWorkspace: string
   private hostBranch: string
   private readonly apiReauthenticator: ApiReauthenticator | undefined
@@ -495,6 +525,14 @@ export class NanobotTui {
       treeSitterClient,
     )
     this.queuePreview = new QueuePreview(renderer, queuePreviewTheme(this.palette))
+    this.recoveryNotice = new RecoveryNotice(
+      renderer,
+      recoveryNoticeTheme(this.palette),
+      {
+        onContinue: () => void this.updateRecovery("continue"),
+        onDismiss: () => void this.updateRecovery("dismiss"),
+      },
+    )
     this.client = client || new NanobotClient({
       ...(options.bootstrapUrl
         ? {
@@ -723,6 +761,7 @@ export class NanobotTui {
     this.shell.add(this.runtimeControls.menuRoot)
     if (!host.hosted) this.shell.add(this.title)
     this.shell.add(this.queuePreview.root)
+    this.shell.add(this.recoveryNotice.root)
     this.shell.add(this.composerFrame)
     this.shell.add(statusRow)
     this.shell.add(this.diffViewer.root)
@@ -831,6 +870,12 @@ export class NanobotTui {
       this.quit()
       return
     }
+    if (["/continue", "/dismiss"].includes(visibleContent.toLowerCase())) {
+      this.clearComposer()
+      this.commandMenu.hide()
+      void this.updateRecovery(visibleContent.toLowerCase() === "/continue" ? "continue" : "dismiss")
+      return
+    }
     const completion = this.commandMenu.completion(visibleContent)
     if (completion) {
       this.setComposer(completion)
@@ -925,6 +970,8 @@ export class NanobotTui {
 
   accept(event: InboundEvent): void {
     if (event.event === "attached") {
+      const switchedSession = Boolean(this.currentChatId && this.currentChatId !== event.chat_id)
+      this.currentChatId = event.chat_id
       this.host.reportSession(event.chat_id)
       if (event.usage) this.lastUsage = event.usage
       if (event.model_preset !== undefined) {
@@ -946,7 +993,11 @@ export class NanobotTui {
       }
       const hydrationId = ++this.hydrationId
       void this.prepareChat(event.chat_id, restoring, hydrationId).then(() => {
-        if (hydrationId === this.hydrationId) this.flushPendingEvents()
+        if (hydrationId !== this.hydrationId) return
+        this.applyRecoveryState(event.recovery_state ?? null)
+        this.flushPendingEvents()
+        this.syncQueuePreview()
+        if (switchedSession) this.sendNextFollowUp()
       })
       return
     }
@@ -1083,6 +1134,9 @@ export class NanobotTui {
         this.applyHostGoalState(event.goal_state)
         if (!this.activeTurn) this.reportHostResting()
         return
+      case "recovery_state":
+        this.applyRecoveryState(event)
+        return
       case "turn_model_updated":
         if (typeof event.context_window_tokens === "number") {
           this.contextWindowTokens = event.context_window_tokens
@@ -1191,6 +1245,87 @@ export class NanobotTui {
     for (const event of events || []) this.accept(event)
   }
 
+  private clearRecoveryState(): void {
+    this.recoveryState = null
+    this.recoveryPending = false
+    this.recoveryNotice.hide()
+  }
+
+  private applyRecoveryState(state: RecoveryState | null): void {
+    if (!state) {
+      this.clearRecoveryState()
+      return
+    }
+    this.recoveryState = state
+    this.recoveryPending = false
+    if (state.status === "resuming") {
+      this.recoveryNotice.hide()
+      this.hostBlocked = false
+      this.activeLabel = "Continuing"
+      this.setCurrentAction("Continuing interrupted task")
+      this.setActive(true)
+      this.reportHostWorking()
+      return
+    }
+    if (state.status === "awaiting_user" || state.status === "failed") {
+      this.activeTurnId = null
+      this.setActive(false)
+      this.hostBlocked = true
+      this.recoveryNotice.show(state)
+      const detail = state.reason || (state.status === "failed"
+        ? "Recovery failed"
+        : "Task interrupted")
+      this.setCurrentAction(detail)
+      this.status.content = state.can_continue === false
+        ? "Interrupted · dismiss to start a new message"
+        : "Interrupted · continue or dismiss"
+      this.host.reportState("blocked", detail)
+      this.composer.focus()
+      return
+    }
+    this.clearRecoveryState()
+    this.activeTurnId = null
+    this.hostBlocked = false
+    this.setActive(false)
+    if (this.ready) this.status.content = this.readyStatus()
+    this.reportHostResting()
+  }
+
+  private async updateRecovery(action: "continue" | "dismiss"): Promise<void> {
+    const state = this.recoveryState
+    if (
+      !state
+      || (state.status !== "awaiting_user" && state.status !== "failed")
+      || (action === "continue" && state.can_continue === false)
+    ) {
+      this.status.content = "No interrupted task"
+      this.composer.focus()
+      return
+    }
+    if (this.recoveryPending) return
+    this.recoveryPending = true
+    this.recoveryNotice.setBusy(true)
+    this.status.content = action === "continue" ? "Continuing…" : "Dismissing…"
+    try {
+      const next = await this.client.updateRecovery(
+        action,
+        this.client.activeChatId,
+        state.recovery_id,
+      )
+      if (this.recoveryState?.recovery_id === state.recovery_id) {
+        this.applyRecoveryState(next)
+      }
+    } catch (error) {
+      if (this.recoveryState?.recovery_id !== state.recovery_id) return
+      this.recoveryPending = false
+      this.recoveryNotice.setBusy(false)
+      this.status.content = error instanceof Error ? error.message : String(error)
+      this.host.reportState("blocked", state.reason || "Task interrupted")
+    } finally {
+      this.composer.focus()
+    }
+  }
+
   private updateGatewayApiConnection(apiUrl: string, apiToken: string): void {
     this.options.apiUrl = apiUrl
     this.options.apiToken = apiToken
@@ -1282,6 +1417,7 @@ export class NanobotTui {
   }
 
   private renderActiveStatus(): void {
+    if (this.sessionLoading || this.sessionMenu.visible) return
     const elapsed = formatElapsed(Date.now() - this.activeStartedAt)
     const navigation = this.transcriptNavigation.awayFromBottom ? " · Ctrl+End latest" : ""
     const queued = this.promptQueue.length ? ` · ${this.promptQueue.length} queued` : ""
@@ -1311,6 +1447,16 @@ export class NanobotTui {
     this.sendPrompt(prompt)
   }
 
+  private get promptQueue(): PromptQueue {
+    const chatId = this.currentChatId || this.client.activeChatId
+    let queue = this.promptQueues.get(chatId)
+    if (!queue) {
+      queue = new PromptQueue()
+      this.promptQueues.set(chatId, queue)
+    }
+    return queue
+  }
+
   private restoreQueuedPrompts(): void {
     const queued = this.promptQueue.restore()
     if (!queued.length) return
@@ -1576,6 +1722,7 @@ export class NanobotTui {
     this.contextPanel.setTheme(contextPanelTheme(this.palette))
     this.diffViewer.setTheme(diffViewerTheme(this.palette, this.backgroundKnown))
     this.queuePreview.setTheme(queuePreviewTheme(this.palette))
+    this.recoveryNotice.setTheme(recoveryNoticeTheme(this.palette))
     this.updateComposerAppearance()
     this.composer.textColor = this.palette.text
     this.composer.focusedTextColor = this.palette.text
@@ -1858,7 +2005,7 @@ export class NanobotTui {
 
   private closeTransientMenus(): void {
     this.commandMenu.hide()
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.mentionMenu.hide()
     this.branchMenu.hide()
     this.contextPanel.hide()
@@ -1912,7 +2059,7 @@ export class NanobotTui {
       return
     }
     this.commandMenu.hide()
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.contextPanel.hide()
     this.clearComposer()
     this.status.content = "Loading branch points…"
@@ -1974,10 +2121,6 @@ export class NanobotTui {
   }
 
   private async openSessions(): Promise<void> {
-    if (this.activeTurn) {
-      this.status.content = "Wait for the current turn or press Ctrl+C"
-      return
-    }
     this.commandMenu.hide()
     this.dismissRuntimeControls()
     this.mentionMenu.hide()
@@ -2001,10 +2144,17 @@ export class NanobotTui {
         this.sessionTitle = sessionLabel(current)
         this.applySessionModel(current)
         this.applySessionScope(current)
+        this.applyRecoveryState(current.recoveryState ?? null)
         this.updateTitle()
       }
       const limit = this.renderer.height >= 20 ? 8 : 4
-      this.sessionMenu.open(sessions, this.client.activeChatId, limit)
+      this.sessionMenu.open(
+        sessions,
+        this.client.activeChatId,
+        limit,
+        this.defaultModelPreset,
+      )
+      this.startSessionRefresh()
       this.renderTitleColor()
       this.sessionMenu.update(this.composer.plainText, limit)
       this.syncComposerPlaceholder()
@@ -2019,17 +2169,14 @@ export class NanobotTui {
   }
 
   private switchSession(session: SessionSummary): void {
-    if (this.activeTurn) {
-      this.status.content = "Wait for the current turn or press Ctrl+C"
-      return
-    }
+    this.sessionMenu.markRead(session.chatId)
     if (session.chatId === this.client.activeChatId) {
       this.sessionTitle = sessionLabel(session)
       this.applySessionModel(session)
       this.applySessionScope(session)
+      this.applyRecoveryState(session.recoveryState ?? null)
       this.updateTitle()
       this.closeSessions()
-      this.status.content = this.readyStatus()
       return
     }
     if (!this.ready) {
@@ -2039,7 +2186,10 @@ export class NanobotTui {
     this.closeSessions()
     try {
       this.ready = false
-      this.clearPromptQueue()
+      this.activeTurnId = null
+      this.setActive(false)
+      this.clearRecoveryState()
+      this.queuePreview.update([])
       this.sessionMetadataId += 1
       this.clearHostContext()
       this.sessionTitle = sessionLabel(session)
@@ -2066,13 +2216,14 @@ export class NanobotTui {
       return
     }
     this.commandMenu.hide()
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.mentionMenu.hide()
     this.branchMenu.hide()
     this.contextPanel.hide()
     this.clearComposer()
     try {
       this.ready = false
+      this.clearRecoveryState()
       this.clearPromptQueue()
       this.sessionMetadataId += 1
       this.clearHostContext()
@@ -2173,18 +2324,65 @@ export class NanobotTui {
   private closeSessions(): void {
     this.sessionLoadId += 1
     this.sessionLoading = false
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.renderTitleColor()
     this.clearComposer()
     this.syncComposerPlaceholder()
     this.composer.focus()
-    if (!this.activeTurn && this.ready) this.status.content = this.readyStatus()
+    if (this.activeTurn) this.renderActiveStatus()
+    else if (this.ready) this.status.content = this.readyStatus()
     this.updateMeta()
   }
 
+  private hideSessionMenu(): void {
+    this.stopSessionRefresh()
+    this.sessionMenu.hide()
+  }
+
+  private startSessionRefresh(): void {
+    if (this.sessionRefreshTimer) return
+    this.sessionRefreshTimer = setInterval(() => {
+      if (!this.sessionMenu.visible) {
+        this.stopSessionRefresh()
+        return
+      }
+      void this.refreshSessionMenu()
+    }, SESSION_REFRESH_INTERVAL_MS)
+    ;(this.sessionRefreshTimer as unknown as { unref?: () => void }).unref?.()
+  }
+
+  private stopSessionRefresh(): void {
+    if (this.sessionRefreshTimer) clearInterval(this.sessionRefreshTimer)
+    this.sessionRefreshTimer = null
+  }
+
+  private async refreshSessionMenu(): Promise<void> {
+    if (this.sessionRefreshPending || !this.sessionMenu.visible || this.quitting) return
+    this.sessionRefreshPending = true
+    const loadId = this.sessionLoadId
+    try {
+      const sessions = await fetchSessions(
+        this.options.apiUrl,
+        this.options.apiToken,
+        this.apiReauthenticator,
+      )
+      if (this.quitting || loadId !== this.sessionLoadId || !this.sessionMenu.visible) return
+      this.sessionMenu.replace(
+        sessions,
+        this.client.activeChatId,
+        this.defaultModelPreset,
+      )
+      this.status.content = sessions.length ? `${sessions.length} sessions` : "No saved sessions"
+    } catch {
+      // Keep the existing picker usable during a transient refresh failure.
+    } finally {
+      this.sessionRefreshPending = false
+    }
+  }
+
   private async openContext(): Promise<void> {
     this.commandMenu.hide()
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.mentionMenu.hide()
     this.branchMenu.hide()
     this.clearComposer()
@@ -2256,7 +2454,7 @@ export class NanobotTui {
 
   private openDiff(): void {
     this.commandMenu.hide()
-    this.sessionMenu.hide()
+    this.hideSessionMenu()
     this.mentionMenu.hide()
     this.branchMenu.hide()
     this.contextPanel.hide()
@@ -2320,6 +2518,7 @@ export class NanobotTui {
     this.quitting = true
     this.submitGeneration += 1
     this.submitPending = false
+    this.stopSessionRefresh()
     this.host.release()
     this.client.close()
     this.renderer.destroy()
@@ -2330,6 +2529,7 @@ export class NanobotTui {
 
   private handleDestroy = (): void => {
     if (this.shimmerTimer) clearInterval(this.shimmerTimer)
+    this.stopSessionRefresh()
     this.transcript.destroy()
     this.diffViewer.destroy()
     this.host.release()

tui/src/picker-menu.ts

@@ -1,22 +1,27 @@
 import {
   BoxRenderable,
   RGBA,
+  StyledText,
   TextAttributes,
   TextRenderable,
   type CliRenderer,
+  type TextChunk,
 } from "@opentui/core"
 
 export interface PickerMenuTheme {
   text: string
   muted: string
   border: string
+  accent?: string
+  warning?: string
   selectedBackground?: string
 }
 
 interface PickerMenuOptions<T> {
   id: string
+  key?: (item: T) => string
   searchText: (item: T) => string
-  render: (item: T) => string
+  render: (item: T, selected: boolean) => string | TextChunk[]
   emptyText?: string
   maxWidth?: number
   onSelect?: (item: T) => void
@@ -68,9 +73,21 @@ export class PickerMenu<T> {
     this.update(query, limit)
   }
 
+  replace(items: T[]): void {
+    if (!this.visible) return
+    this.items = items
+    this.update(this.query, this.limit)
+  }
+
+  redraw(): void {
+    if (this.visible) this.render()
+  }
+
   update(query: string, limit = this.limit): void {
     if (!this.visible) return
     const changed = query !== this.query
+    const previous = this.matches[this.selected]
+    const previousKey = previous === undefined ? null : this.options.key?.(previous)
     this.query = query
     this.limit = Math.max(1, limit)
     const words = query.trim().toLocaleLowerCase().split(/\s+/u).filter(Boolean)
@@ -80,7 +97,18 @@ export class PickerMenu<T> {
         return words.every((word) => haystack.includes(word))
       })
       .slice(0, this.limit)
-    this.selected = changed ? 0 : Math.min(this.selected, Math.max(0, this.matches.length - 1))
+    if (changed) {
+      this.selected = 0
+    } else {
+      const preserved = previous === undefined
+        ? -1
+        : previousKey === null || previousKey === undefined
+          ? this.matches.indexOf(previous)
+          : this.matches.findIndex((item) => this.options.key?.(item) === previousKey)
+      this.selected = preserved >= 0
+        ? preserved
+        : Math.min(this.selected, Math.max(0, this.matches.length - 1))
+    }
     this.render()
   }
 
@@ -125,9 +153,16 @@ export class PickerMenu<T> {
     }
     for (const [index, item] of this.matches.entries()) {
       const selected = index === this.selected
+      const rendered = this.options.render(item, selected)
+      const content = typeof rendered === "string"
+        ? `${selected ? "›" : " "} ${rendered}`
+        : new StyledText([
+            chunk(`${selected ? "›" : " "} `, selected ? this.theme.text : this.theme.muted),
+            ...rendered,
+          ])
       this.root.add(new TextRenderable(this.renderer, {
         id: `${this.options.id}-${index}`,
-        content: `${selected ? "›" : " "} ${this.options.render(item)}`,
+        content,
         width: "100%",
         height: 1,
         wrapMode: "none",
@@ -161,3 +196,11 @@ export class PickerMenu<T> {
     }
   }
 }
+
+function chunk(text: string, color: string): TextChunk {
+  return {
+    __isChunk: true,
+    text,
+    fg: RGBA.fromHex(color),
+  }
+}

tui/src/protocol.test.ts

@@ -595,6 +595,62 @@ describe("gateway protocol", () => {
     }
   })
 
+  test("sends stale-safe recovery mutations and validates their response", async () => {
+    const original = globalThis.WebSocket
+    let socket: FakeSocket | undefined
+    Object.defineProperty(globalThis, "WebSocket", {
+      configurable: true,
+      value: class extends FakeSocket {
+        constructor() {
+          super()
+          socket = this
+        }
+      },
+    })
+
+    try {
+      const statuses: string[] = []
+      const client = new NanobotClient({
+        url: "ws://nanobot.test/ws",
+        onEvent: () => undefined,
+        onStatus: (status, detail) => statuses.push(`${status}:${detail || ""}`),
+      })
+      client.connect()
+      if (!socket) throw new Error("socket was not created")
+
+      const result = client.updateRecovery("continue", "chat", "recovery-1")
+      const request = JSON.parse(socket.sent.at(-1) || "{}") as {
+        request_id: string
+        action: string
+        payload: Record<string, string>
+      }
+      expect(request).toMatchObject({
+        type: "webui_request",
+        action: "recovery.continue",
+        payload: { chat_id: "chat", recovery_id: "recovery-1" },
+      })
+      socket.emit("message", { data: JSON.stringify({
+        event: "webui_response",
+        request_id: request.request_id,
+        ok: true,
+        result: { status: "resuming", recovery_id: "recovery-1", attempts: 1 },
+      }) })
+      expect(await result).toEqual({
+        status: "resuming",
+        recovery_id: "recovery-1",
+        attempts: 1,
+      })
+      expect(statuses).not.toContain("error:gateway sent an invalid event")
+
+      const interrupted = client.updateRecovery("dismiss", "chat", "recovery-2")
+      socket.emit("close")
+      await expect(interrupted).rejects.toThrow("gateway connection closed")
+      client.close()
+    } finally {
+      Object.defineProperty(globalThis, "WebSocket", { configurable: true, value: original })
+    }
+  })
+
   test("reports when the bounded history snapshot omits earlier turns", async () => {
     const original = globalThis.fetch
     let requested = ""

tui/src/protocol.ts

@@ -54,6 +54,16 @@ export interface RuntimeControls {
   canUseFullAccess: boolean
 }
 
+export type RecoveryStatus = "resuming" | "awaiting_user" | "recovered" | "failed"
+
+export interface RecoveryState {
+  status: RecoveryStatus
+  recovery_id: string
+  reason?: string
+  attempts?: number
+  can_continue?: boolean
+}
+
 export type InboundEvent =
   | { event: "ready"; chat_id: string; client_id: string }
   | {
@@ -61,6 +71,7 @@ export type InboundEvent =
       chat_id: string
       model_preset?: string | null
       usage?: TokenUsage
+      recovery_state?: RecoveryState
     }
   | {
       event: "message_accepted"
@@ -118,6 +129,7 @@ export type InboundEvent =
       turn_id?: string
     }
   | { event: "goal_state"; chat_id: string; goal_state: Record<string, unknown> }
+  | ({ event: "recovery_state"; chat_id: string } & RecoveryState)
   | {
       event: "session_updated"
       chat_id: string
@@ -139,6 +151,12 @@ type OutboundEvent =
   | { type: "fork_chat"; source_chat_id: string; before_user_index: number; title?: string }
   | { type: "attach"; chat_id: string }
   | { type: "set_workspace_scope"; chat_id: string; workspace_scope: WorkspaceScopePayload }
+  | {
+      type: "webui_request"
+      request_id: string
+      action: string
+      payload: Record<string, unknown>
+    }
   | {
       type: "message"
       chat_id: string
@@ -271,6 +289,7 @@ export interface SessionSummary {
   updatedAt: string | null
   runStartedAt: number | null
   modelPreset: string | null
+  recoveryState?: RecoveryState | null
   workspaceScope?: WorkspaceScopePayload | null
   pinned: boolean
   archived: boolean
@@ -297,6 +316,7 @@ const CHAT_EVENTS = new Set([
   "turn_end",
   "goal_status",
   "goal_state",
+  "recovery_state",
   "session_updated",
   "turn_model_updated",
   "error",
@@ -377,6 +397,34 @@ function isWorkspaceScope(value: unknown): value is WorkspaceScopePayload {
     && optional(value.restrict_to_workspace, "boolean")
 }
 
+function isRecoveryState(value: unknown): value is RecoveryState {
+  return isRecord(value)
+    && ["resuming", "awaiting_user", "recovered", "failed"].includes(String(value.status))
+    && typeof value.recovery_id === "string"
+    && optional(value.reason, "string")
+    && optional(value.attempts, "number")
+    && optional(value.can_continue, "boolean")
+}
+
+interface WebUIResponseEvent {
+  event: "webui_response"
+  request_id: string
+  ok: boolean
+  result?: unknown
+  error?: { status: number; message: string }
+}
+
+function decodeWebUIResponse(value: unknown): WebUIResponseEvent | null | undefined {
+  if (!isRecord(value) || value.event !== "webui_response") return undefined
+  if (typeof value.request_id !== "string" || typeof value.ok !== "boolean") return null
+  if (value.ok) return value as unknown as WebUIResponseEvent
+  return isRecord(value.error)
+    && typeof value.error.status === "number"
+    && typeof value.error.message === "string"
+    ? value as unknown as WebUIResponseEvent
+    : null
+}
+
 function decodeInboundEvent(value: unknown): InboundEvent | null | undefined {
   if (!isRecord(value)) return null
   const record = value
@@ -407,7 +455,8 @@ function decodeInboundEvent(value: unknown): InboundEvent | null | undefined {
     && ((record.model_preset !== undefined
       && record.model_preset !== null
       && typeof record.model_preset !== "string")
-      || (record.usage !== undefined && !isTokenUsage(record.usage)))
+      || (record.usage !== undefined && !isTokenUsage(record.usage))
+      || (record.recovery_state !== undefined && !isRecoveryState(record.recovery_state)))
   ) return null
   if (
     ["user_message", "message", "delta", "reasoning_delta"].includes(name)
@@ -452,6 +501,7 @@ function decodeInboundEvent(value: unknown): InboundEvent | null | undefined {
   ) return null
   if (name === "goal_status" && record.status !== "running" && record.status !== "idle") return null
   if (name === "goal_state" && !isRecord(record.goal_state)) return null
+  if (name === "recovery_state" && !isRecoveryState(record)) return null
   if (
     name === "session_updated"
     && (!optional(record.scope, "string")
@@ -700,6 +750,9 @@ export async function fetchSessions(
       modelPreset: typeof value.model_preset === "string" && value.model_preset.trim()
         ? value.model_preset.trim()
         : null,
+      ...(isRecoveryState(value.recovery_state)
+        ? { recoveryState: value.recovery_state }
+        : {}),
       ...(isWorkspaceScope(value.workspace_scope) ? { workspaceScope: value.workspace_scope } : {}),
       pinned: pinned.has(value.key),
       archived: archived.has(value.key),
@@ -855,6 +908,11 @@ export class NanobotClient {
   private closedByClient = false
   private opening = false
   private connectedOnce = false
+  private readonly pendingMutations = new Map<string, {
+    resolve: (value: unknown) => void
+    reject: (error: Error) => void
+    timer: ReturnType<typeof setTimeout>
+  }>()
 
   constructor(private readonly options: ClientOptions) {}
 
@@ -916,6 +974,7 @@ export class NanobotClient {
     socket.addEventListener("close", () => {
       if (this.socket !== socket) return
       this.socket = null
+      this.rejectPendingMutations("gateway connection closed")
       if (this.closedByClient) {
         this.options.onStatus("closed")
         return
@@ -931,6 +990,7 @@ export class NanobotClient {
     const socket = this.socket
     this.socket = null
     socket?.close()
+    this.rejectPendingMutations("gateway connection closed")
   }
 
   send(content: string, options: MessageOptions = {}): string {
@@ -975,6 +1035,63 @@ export class NanobotClient {
     this.write({ type: "set_workspace_scope", chat_id: this.chatId, workspace_scope: scope })
   }
 
+  updateRecovery(
+    action: "continue" | "dismiss",
+    chatId: string,
+    recoveryId: string,
+  ): Promise<RecoveryState> {
+    return this.requestMutation<unknown>(`recovery.${action}`, {
+      chat_id: chatId,
+      recovery_id: recoveryId,
+    }).then((result) => {
+      if (!isRecoveryState(result)) throw new Error("gateway returned an invalid recovery state")
+      return result
+    })
+  }
+
+  private requestMutation<T>(
+    action: string,
+    payload: Record<string, unknown> = {},
+    timeoutMs = 20_000,
+  ): Promise<T> {
+    if (!this.socket || this.socket.readyState !== WebSocket.OPEN) {
+      return Promise.reject(new Error("gateway connection is not open"))
+    }
+    const requestId = crypto.randomUUID()
+    const frame = JSON.stringify({
+      type: "webui_request",
+      request_id: requestId,
+      action,
+      payload,
+    } satisfies OutboundEvent)
+    return new Promise<T>((resolve, reject) => {
+      const timer = setTimeout(() => {
+        this.pendingMutations.delete(requestId)
+        reject(new Error(`gateway request timed out after ${timeoutMs}ms`))
+      }, timeoutMs)
+      this.pendingMutations.set(requestId, {
+        resolve: (value) => resolve(value as T),
+        reject,
+        timer,
+      })
+      try {
+        this.socket?.send(frame)
+      } catch {
+        clearTimeout(timer)
+        this.pendingMutations.delete(requestId)
+        reject(new Error("could not send gateway request"))
+      }
+    })
+  }
+
+  private rejectPendingMutations(message: string): void {
+    for (const pending of this.pendingMutations.values()) {
+      clearTimeout(pending.timer)
+      pending.reject(new Error(message))
+    }
+    this.pendingMutations.clear()
+  }
+
   private handleMessage(raw: string): void {
     let value: unknown
     try {
@@ -983,6 +1100,20 @@ export class NanobotClient {
       this.options.onStatus("error", "gateway sent invalid JSON")
       return
     }
+    const response = decodeWebUIResponse(value)
+    if (response === null) {
+      this.options.onStatus("error", "gateway sent an invalid event")
+      return
+    }
+    if (response) {
+      const pending = this.pendingMutations.get(response.request_id)
+      if (!pending) return
+      clearTimeout(pending.timer)
+      this.pendingMutations.delete(response.request_id)
+      if (response.ok) pending.resolve(response.result)
+      else pending.reject(new Error(response.error?.message || "gateway request failed"))
+      return
+    }
     const event = decodeInboundEvent(value)
     if (event === undefined) return
     if (event === null) {

tui/src/recovery-notice.ts

@@ -0,0 +1,177 @@
+import {
+  BoxRenderable,
+  RGBA,
+  StyledText,
+  TextAttributes,
+  TextRenderable,
+  type CliRenderer,
+  type TextChunk,
+} from "@opentui/core"
+
+import type { RecoveryState } from "./protocol"
+
+export interface RecoveryNoticeTheme {
+  text: string
+  muted: string
+  border: string
+  accent: string
+  warning: string
+  error: string
+}
+
+interface RecoveryNoticeOptions {
+  onContinue: () => void
+  onDismiss: () => void
+}
+
+/** A quiet action surface for a gateway-owned interrupted turn. */
+export class RecoveryNotice {
+  readonly root: BoxRenderable
+  private readonly title: TextRenderable
+  private readonly detail: TextRenderable
+  private readonly dismiss: TextRenderable
+  private readonly resume: TextRenderable
+  private state: RecoveryState | null = null
+  private busy = false
+
+  constructor(
+    renderer: CliRenderer,
+    private theme: RecoveryNoticeTheme,
+    options: RecoveryNoticeOptions,
+  ) {
+    this.root = new BoxRenderable(renderer, {
+      id: "nanobot-tui-recovery-notice",
+      width: "100%",
+      height: 4,
+      flexShrink: 0,
+      flexDirection: "column",
+      border: true,
+      borderStyle: "rounded",
+      borderColor: theme.border,
+      paddingLeft: 1,
+      paddingRight: 1,
+      visible: false,
+      backgroundColor: RGBA.defaultBackground(),
+    })
+    const header = new BoxRenderable(renderer, {
+      id: "nanobot-tui-recovery-header",
+      width: "100%",
+      height: 1,
+      flexDirection: "row",
+      alignItems: "center",
+      gap: 2,
+    })
+    this.title = new TextRenderable(renderer, {
+      id: "nanobot-tui-recovery-title",
+      width: "auto",
+      minWidth: 0,
+      flexGrow: 1,
+      height: 1,
+      truncate: true,
+      selectable: false,
+    })
+    this.detail = new TextRenderable(renderer, {
+      id: "nanobot-tui-recovery-detail",
+      width: "100%",
+      height: 1,
+      truncate: true,
+      selectable: false,
+    })
+    this.dismiss = this.action(renderer, "dismiss", "Dismiss", options.onDismiss)
+    this.resume = this.action(renderer, "continue", "Continue", options.onContinue, true)
+    header.add(this.title)
+    header.add(this.dismiss)
+    header.add(this.resume)
+    this.root.add(header)
+    this.root.add(this.detail)
+  }
+
+  get visible(): boolean {
+    return this.root.visible
+  }
+
+  show(state: RecoveryState): void {
+    this.state = state
+    this.busy = false
+    this.root.visible = true
+    this.render()
+  }
+
+  hide(): void {
+    this.state = null
+    this.busy = false
+    this.root.visible = false
+  }
+
+  setBusy(busy: boolean): void {
+    this.busy = busy
+    if (this.visible) this.render()
+  }
+
+  setTheme(theme: RecoveryNoticeTheme): void {
+    this.theme = theme
+    this.root.borderColor = theme.border
+    if (this.visible) this.render()
+  }
+
+  private action(
+    renderer: CliRenderer,
+    id: string,
+    label: string,
+    callback: () => void,
+    primary = false,
+  ): TextRenderable {
+    return new TextRenderable(renderer, {
+      id: `nanobot-tui-recovery-${id}`,
+      content: label,
+      width: label.length,
+      height: 1,
+      flexShrink: 0,
+      selectable: false,
+      onMouseOver: () => {
+        if (this.busy) return
+        const target = primary ? this.resume : this.dismiss
+        target.attributes = TextAttributes.BOLD | TextAttributes.UNDERLINE
+      },
+      onMouseOut: () => this.render(),
+      onMouseDown: (event) => {
+        if (event.button !== 0 || this.busy) return
+        event.preventDefault()
+        event.stopPropagation()
+        renderer.clearSelection()
+        callback()
+      },
+    })
+  }
+
+  private render(): void {
+    if (!this.state) return
+    const failed = this.state.status === "failed"
+    const contextUnavailable = this.state.can_continue === false
+    const title = failed ? "Recovery failed" : "Task interrupted"
+    const detail = failed
+      ? "Review the saved task before continuing."
+      : contextUnavailable
+        ? "This task can’t be resumed safely. Dismiss to start a new message."
+        : "Review the saved context. Tools will not replay automatically."
+    this.title.content = new StyledText([
+      chunk("⚠ ", failed ? this.theme.error : this.theme.warning),
+      chunk(title, this.theme.text, true),
+    ])
+    this.detail.content = new StyledText([chunk(`  ${detail}`, this.theme.muted)])
+    this.dismiss.fg = RGBA.fromHex(this.busy ? this.theme.muted : this.theme.text)
+    this.resume.visible = !contextUnavailable
+    this.resume.fg = RGBA.fromHex(this.busy ? this.theme.muted : this.theme.accent)
+    this.dismiss.attributes = 0
+    this.resume.attributes = TextAttributes.BOLD
+  }
+}
+
+function chunk(text: string, color: string, bold = false): TextChunk {
+  return {
+    __isChunk: true,
+    text,
+    fg: RGBA.fromHex(color),
+    attributes: bold ? TextAttributes.BOLD : 0,
+  }
+}

tui/src/session-menu.test.ts

@@ -24,6 +24,11 @@ const sessions: SessionSummary[] = [
     updatedAt: "2026-08-12T10:00:00Z",
     runStartedAt: null,
     modelPreset: null,
+    recoveryState: {
+      status: "awaiting_user",
+      recovery_id: "recovery-two",
+      reason: "tool execution interrupted",
+    },
     pinned: false,
     archived: false,
   },
@@ -43,17 +48,21 @@ describe("SessionMenu", () => {
       text: "#FFFFFF",
       muted: "#999999",
       border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
     })
     setup.renderer.root.add(menu.root)
-    menu.open(sessions, "one", 6)
+    menu.open(sessions, "one", 6, "Codex")
     await setup.renderOnce()
 
     expect(setup.captureCharFrame()).toContain("› ● API migration")
+    expect(setup.captureCharFrame()).not.toContain("Move authentication")
+    expect(setup.captureCharFrame()).not.toContain("Codex")
     expect(menu.choose()?.chatId).toBe("one")
 
     menu.update("release stable", 6)
     await setup.renderOnce()
-    expect(setup.captureCharFrame()).toContain("Release checklist")
+    expect(setup.captureCharFrame()).toContain("⚠ Release checklist")
     expect(menu.choose()?.chatId).toBe("two")
   })
 
@@ -63,12 +72,80 @@ describe("SessionMenu", () => {
     )
   })
 
+  test("animates running sessions and marks completed background sessions unread", async () => {
+    setup = await createTestRenderer({ width: 80, height: 18, screenMode: "alternate-screen" })
+    const menu = new SessionMenu(setup.renderer, {
+      text: "#FFFFFF",
+      muted: "#999999",
+      border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
+    })
+    setup.renderer.root.add(menu.root)
+    const running = {
+      ...sessions[0]!,
+      chatId: "running",
+      title: "Background task",
+      runStartedAt: Date.now(),
+      pinned: false,
+    }
+
+    menu.open([sessions[0]!, running], "one", 6)
+    await setup.renderOnce()
+    expect(setup.captureCharFrame()).toMatch(/[⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏] Background task/u)
+
+    menu.replace([{ ...sessions[0]! }, { ...running, runStartedAt: null }], "one")
+    await setup.renderOnce()
+    expect(setup.captureCharFrame()).toContain("• Background task")
+
+    menu.markRead("running")
+    menu.replace([{ ...sessions[0]! }, { ...running, runStartedAt: null }], "running")
+    await setup.renderOnce()
+    expect(setup.captureCharFrame()).toContain("● Background task")
+    menu.hide()
+  })
+
+  test("prioritizes actionable sessions without moving keyboard selection on refresh", async () => {
+    setup = await createTestRenderer({ width: 80, height: 18, screenMode: "alternate-screen" })
+    const menu = new SessionMenu(setup.renderer, {
+      text: "#FFFFFF",
+      muted: "#999999",
+      border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
+    })
+    setup.renderer.root.add(menu.root)
+    const running = {
+      ...sessions[0]!,
+      chatId: "running",
+      title: "Background task",
+      runStartedAt: Date.now(),
+      pinned: false,
+    }
+
+    const idle = { ...sessions[1]!, recoveryState: null }
+    menu.open([sessions[0]!, running, idle], "one", 6)
+    expect(menu.choose()?.chatId).toBe("one")
+    expect(menu.move(1)).toBe(true)
+    expect(menu.choose()?.chatId).toBe("running")
+
+    menu.replace([sessions[0]!, running, sessions[1]!], "one")
+    await setup.renderOnce()
+
+    expect(menu.choose()?.chatId).toBe("running")
+    const frame = setup.captureCharFrame()
+    expect(frame.indexOf("Release checklist")).toBeLessThan(frame.indexOf("Background task"))
+    menu.hide()
+  })
+
   test("keeps keyboard selection when the pointer stays over the previous row", async () => {
     setup = await createTestRenderer({ width: 80, height: 18, screenMode: "alternate-screen" })
     const menu = new SessionMenu(setup.renderer, {
       text: "#FFFFFF",
       muted: "#999999",
       border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
     })
     setup.renderer.root.add(menu.root)
     menu.open(sessions, "one", 6)
@@ -97,6 +174,8 @@ describe("SessionMenu", () => {
       text: "#FFFFFF",
       muted: "#999999",
       border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
     })
     setup.renderer.root.add(menu.root)
     const scoped = sessions.map((session) => ({
@@ -154,4 +233,31 @@ describe("SessionMenu", () => {
     expect(duplicates).toContain("frontend/nanobot")
     expect(duplicates).toContain("backend/nanobot")
   })
+
+  test("shows only model overrides and keeps previews searchable", async () => {
+    setup = await createTestRenderer({ width: 80, height: 18, screenMode: "alternate-screen" })
+    const menu = new SessionMenu(setup.renderer, {
+      text: "#FFFFFF",
+      muted: "#999999",
+      border: "#555555",
+      accent: "#FF8A33",
+      warning: "#F5C451",
+    })
+    setup.renderer.root.add(menu.root)
+
+    menu.open(sessions, "one", 6, "Codex")
+    await setup.renderOnce()
+    const frame = setup.captureCharFrame()
+    expect(frame).not.toContain("Codex")
+    expect(frame).not.toContain("Prepare the stable release")
+
+    menu.update("prepare stable", 6)
+    await setup.renderOnce()
+    expect(menu.choose()?.chatId).toBe("two")
+
+    menu.replace([{ ...sessions[1]!, modelPreset: "Deep Research" }], "one", "Codex")
+    await setup.renderOnce()
+    expect(setup.captureCharFrame()).toContain("Deep Research")
+    menu.hide()
+  })
 })

tui/src/session-menu.ts

@@ -1,9 +1,11 @@
-import { type BoxRenderable, type CliRenderer } from "@opentui/core"
+import { RGBA, type BoxRenderable, type CliRenderer, type TextChunk } from "@opentui/core"
 
 import { PickerMenu, type PickerMenuTheme } from "./picker-menu"
 import type { SessionSummary } from "./protocol"
 
-type SessionMenuRow = SessionSummary & { active: boolean }
+type SessionMenuRow = SessionSummary & { active: boolean; unread: boolean }
+
+const SPINNER_FRAMES = ["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"]
 
 export function sessionLabel(session: SessionSummary): string {
   const label = session.title.trim() || session.preview.trim() || "Untitled chat"
@@ -27,14 +29,24 @@ export class SessionMenu {
   private readonly picker: PickerMenu<SessionMenuRow>
   private readonly workspaceLabels = new Map<string, string>()
   private showWorkspaces = false
+  private spinnerFrame = 0
+  private spinnerTimer: ReturnType<typeof setInterval> | null = null
+  private rows: SessionMenuRow[] = []
+  private defaultModelPreset = ""
+  private readonly snapshots = new Map<string, {
+    preview: string
+    runStartedAt: number | null
+  }>()
+  private readonly unreadChatIds = new Set<string>()
 
   constructor(
     renderer: CliRenderer,
-    theme: PickerMenuTheme,
+    private theme: PickerMenuTheme,
     onSelect?: (session: SessionSummary) => void,
   ) {
     this.picker = new PickerMenu<SessionMenuRow>(renderer, theme, {
       id: "nanobot-tui-session-menu",
+      key: (session) => session.chatId,
       searchText: (session) => [
         sessionLabel(session),
         session.modelPreset || "",
@@ -42,20 +54,27 @@ export class SessionMenu {
         session.chatId,
         session.workspaceScope?.project_name || "",
         session.workspaceScope?.project_path || "",
+        session.recoveryState?.status || "",
+        session.recoveryState?.reason || "",
       ].join(" "),
-      render: (session) => {
+      render: (session, selected) => {
         const age = updatedLabel(session.updatedAt)
-        const preview = session.preview.trim()
         const detail = [
           this.showWorkspaces ? this.workspaceLabel(session) : "",
-          session.modelPreset,
-          age,
-          preview && preview !== sessionLabel(session) ? preview : "",
+          this.modelOverride(session),
         ]
           .filter(Boolean)
           .join(" · ")
-        const marker = session.active ? "● " : session.pinned ? "◆ " : session.archived ? "◇ " : ""
-        return `${marker}${sessionLabel(session)}${detail ? `  ${detail}` : ""}`
+        const marker = this.marker(session)
+        const foreground = this.interrupted(session)
+          ? this.theme.warning || this.theme.accent || this.theme.text
+          : selected ? this.theme.text : this.theme.muted
+        return [
+          ...(marker ? [chunk(`${marker.text} `, marker.color)] : []),
+          chunk(sessionLabel(session), foreground),
+          ...(detail ? [chunk(`  ${detail}`, this.theme.muted)] : []),
+          ...(age ? [chunk(`  ${age}`, this.theme.muted)] : []),
+        ]
       },
       emptyText: "No matching sessions",
       onSelect,
@@ -67,16 +86,51 @@ export class SessionMenu {
     return this.picker.visible
   }
 
-  open(sessions: SessionSummary[], currentChatId: string, limit: number): void {
+  open(
+    sessions: SessionSummary[],
+    currentChatId: string,
+    limit: number,
+    defaultModelPreset = "",
+  ): void {
+    this.defaultModelPreset = defaultModelPreset
+    this.observe(sessions, currentChatId)
+    this.rows = this.prepareRows(sessions, currentChatId)
+    this.picker.show(this.rows, "", limit)
+    this.syncSpinner()
+  }
+
+  replace(
+    sessions: SessionSummary[],
+    currentChatId: string,
+    defaultModelPreset = this.defaultModelPreset,
+  ): void {
+    this.defaultModelPreset = defaultModelPreset
+    this.observe(sessions, currentChatId)
+    this.rows = this.prepareRows(sessions, currentChatId)
+    this.picker.replace(this.rows)
+    this.syncSpinner()
+  }
+
+  markRead(chatId: string): void {
+    this.unreadChatIds.delete(chatId)
+  }
+
+  private prepareRows(sessions: SessionSummary[], currentChatId: string): SessionMenuRow[] {
     this.prepareWorkspaceLabels(sessions)
-    const rows = sessions
-      .map((session) => ({ ...session, active: session.chatId === currentChatId }))
+    return sessions
+      .map((session) => ({
+        ...session,
+        active: session.chatId === currentChatId,
+        unread: this.unreadChatIds.has(session.chatId),
+      }))
       .sort((left, right) => {
         return Number(right.active) - Number(left.active)
+          || sessionPriority(right) - sessionPriority(left)
           || Number(right.pinned) - Number(left.pinned)
           || Number(left.archived) - Number(right.archived)
+          || timestamp(right.updatedAt) - timestamp(left.updatedAt)
+          || sessionLabel(left).localeCompare(sessionLabel(right))
       })
-    this.picker.show(rows, "", limit)
   }
 
   update(query: string, limit: number): void {
@@ -92,13 +146,84 @@ export class SessionMenu {
   }
 
   hide(): void {
+    this.stopSpinner()
+    this.rows = []
     this.picker.hide()
   }
 
   setTheme(theme: PickerMenuTheme): void {
+    this.theme = theme
     this.picker.setTheme(theme)
   }
 
+  private marker(session: SessionMenuRow): { text: string; color: string } | null {
+    if (this.interrupted(session)) {
+      return {
+        text: "⚠",
+        color: this.theme.warning || this.theme.accent || this.theme.text,
+      }
+    }
+    if (session.runStartedAt !== null) {
+      return {
+        text: SPINNER_FRAMES[this.spinnerFrame % SPINNER_FRAMES.length] || SPINNER_FRAMES[0]!,
+        color: this.theme.accent || this.theme.text,
+      }
+    }
+    if (session.active) return { text: "●", color: this.theme.text }
+    if (session.unread) return { text: "•", color: this.theme.accent || this.theme.text }
+    if (session.pinned) return { text: "◆", color: this.theme.muted }
+    if (session.archived) return { text: "◇", color: this.theme.muted }
+    return null
+  }
+
+  private interrupted(session: SessionMenuRow): boolean {
+    return session.recoveryState?.status === "awaiting_user"
+      || session.recoveryState?.status === "failed"
+  }
+
+  private observe(sessions: SessionSummary[], currentChatId: string): void {
+    const present = new Set<string>()
+    for (const session of sessions) {
+      present.add(session.chatId)
+      const previous = this.snapshots.get(session.chatId)
+      const active = session.chatId === currentChatId
+      const completed = previous !== undefined
+        && previous.runStartedAt !== null
+        && session.runStartedAt === null
+      const receivedContent = previous !== undefined && previous.preview !== session.preview
+      if (active) this.unreadChatIds.delete(session.chatId)
+      else if (completed || receivedContent) this.unreadChatIds.add(session.chatId)
+      this.snapshots.set(session.chatId, {
+        preview: session.preview,
+        runStartedAt: session.runStartedAt,
+      })
+    }
+    for (const chatId of this.snapshots.keys()) {
+      if (present.has(chatId)) continue
+      this.snapshots.delete(chatId)
+      this.unreadChatIds.delete(chatId)
+    }
+  }
+
+  private syncSpinner(): void {
+    if (!this.visible || !this.rows.some((session) => session.runStartedAt !== null)) {
+      this.stopSpinner()
+      return
+    }
+    if (this.spinnerTimer) return
+    this.spinnerTimer = setInterval(() => {
+      this.spinnerFrame = (this.spinnerFrame + 1) % SPINNER_FRAMES.length
+      this.picker.redraw()
+    }, 90)
+    ;(this.spinnerTimer as unknown as { unref?: () => void }).unref?.()
+  }
+
+  private stopSpinner(): void {
+    if (this.spinnerTimer) clearInterval(this.spinnerTimer)
+    this.spinnerTimer = null
+    this.spinnerFrame = 0
+  }
+
   private prepareWorkspaceLabels(sessions: SessionSummary[]): void {
     this.workspaceLabels.clear()
     const scopes = sessions.flatMap((session) => {
@@ -122,6 +247,19 @@ export class SessionMenu {
   private workspaceLabel(session: SessionSummary): string {
     return this.workspaceLabels.get(normalizeWorkspacePath(session.workspaceScope?.project_path)) || ""
   }
+
+  private modelOverride(session: SessionSummary): string {
+    const preset = session.modelPreset?.trim() || ""
+    return preset && preset !== this.defaultModelPreset ? preset : ""
+  }
+}
+
+function chunk(text: string, color: string): TextChunk {
+  return {
+    __isChunk: true,
+    text,
+    fg: RGBA.fromHex(color),
+  }
 }
 
 function normalizeWorkspacePath(value: string | undefined): string {
@@ -136,3 +274,16 @@ function shortPath(path: string): string {
   const parts = path.split("/").filter(Boolean)
   return parts.slice(-2).join("/") || path
 }
+
+function sessionPriority(session: SessionMenuRow): number {
+  if (session.recoveryState?.status === "awaiting_user"
+    || session.recoveryState?.status === "failed") return 3
+  if (session.runStartedAt !== null) return 2
+  return session.unread ? 1 : 0
+}
+
+function timestamp(value: string | null): number {
+  if (!value) return 0
+  const parsed = Date.parse(value)
+  return Number.isNaN(parsed) ? 0 : parsed
+}

webui/src/App.tsx

@@ -1274,6 +1274,15 @@ function Shell({
   }, [activeKey, activeTabKey, activeTabState]);
   const runningChatIdList = useMemo(() => Array.from(runningChatIds), [runningChatIds]);
   const updatedChatIdList = useMemo(() => Array.from(updatedChatIds), [updatedChatIds]);
+  const recoveryChatIdList = useMemo(
+    () => sessions
+      .filter((session) => (
+        session.recoveryState?.status === "awaiting_user"
+        || session.recoveryState?.status === "failed"
+      ))
+      .map((session) => session.chatId),
+    [sessions],
+  );
   const activeChatId = activePaneSession?.chatId ?? null;
   useEffect(() => {
     activeChatIdRef.current = activeChatId;
@@ -2552,6 +2561,7 @@ function Shell({
     collapsedGroups: sidebarState.collapsed_groups,
     runningChatIds: runningChatIdList,
     updatedChatIds: updatedChatIdList,
+    recoveryChatIds: recoveryChatIdList,
     viewState: { ...sidebarState.view, sort: automaticSidebarSort },
     showArchived: sidebarState.view.show_archived,
     archivedCount: sidebarArchivedTabKeys.length,

webui/src/components/ChatList.tsx

@@ -11,6 +11,7 @@ import type { CSSProperties, MouseEvent as ReactMouseEvent, ReactElement } from
 import {
   Archive,
   ArchiveRestore,
+  AlertTriangle,
   ChevronDown,
   Folder,
   FolderTree,
@@ -260,6 +261,7 @@ interface ChatListProps {
   collapsedGroups?: Record<string, boolean>;
   runningChatIds?: string[];
   updatedChatIds?: string[];
+  recoveryChatIds?: string[];
   density?: SidebarDensity;
   showPreviews?: boolean;
   showTimestamps?: boolean;
@@ -302,6 +304,7 @@ export const ChatList = memo(function ChatList({
   collapsedGroups = {},
   runningChatIds = [],
   updatedChatIds = [],
+  recoveryChatIds = [],
   density = "comfortable",
   showPreviews = false,
   showTimestamps = false,
@@ -558,6 +561,7 @@ export const ChatList = memo(function ChatList({
 
   const running = new Set(runningChatIds);
   const updated = new Set(updatedChatIds);
+  const recovery = new Set(recoveryChatIds);
   const compact = density === "compact";
   const firstProjectGroupIndex = limitedGroups.findIndex((group) => group.kind === "project");
   const selectableDeleteKeys = Array.from(new Set(limitedGroups.flatMap((group) => (
@@ -881,6 +885,7 @@ export const ChatList = memo(function ChatList({
                                   compact={compact}
                                   running={running}
                                   updated={updated}
+                                  recovery={recovery}
                                   onSelectPane={onSelectPane}
                                   onRequestDelete={onRequestDelete}
                                   onRequestRename={onRequestRename}
@@ -915,9 +920,11 @@ export const ChatList = memo(function ChatList({
                       : "";
                     const activityState = running.has(s.chatId)
                       ? "running"
-                      : updated.has(s.chatId) && !topicActive
-                        ? "updated"
-                        : null;
+                      : recovery.has(s.chatId)
+                        ? "recovery"
+                        : updated.has(s.chatId) && !topicActive
+                          ? "updated"
+                          : null;
                     const hasPaneMoveTarget = Boolean(onAttachPane)
                       && paneGroupTargets.some((target) => (
                         target.key !== paneGroup?.tabKey && !target.atCapacity
@@ -1330,6 +1337,7 @@ function ActivePaneRows({
   compact,
   running,
   updated,
+  recovery,
   onSelectPane,
   onRequestDelete,
   onRequestRename,
@@ -1354,6 +1362,7 @@ function ActivePaneRows({
   compact: boolean;
   running: ReadonlySet<string>;
   updated: ReadonlySet<string>;
+  recovery: ReadonlySet<string>;
   onSelectPane?: (tabKey: string, paneKey: string) => void;
   onRequestDelete: (key: string, label: string) => void;
   onRequestRename: (key: string, label: string) => void;
@@ -1390,9 +1399,11 @@ function ActivePaneRows({
         const active = tabActive && pane.key === group.activePaneKey;
         const activityState = running.has(pane.chatId)
           ? "running"
-          : updated.has(pane.chatId) && !active
-            ? "updated"
-            : null;
+          : recovery.has(pane.chatId)
+            ? "recovery"
+            : updated.has(pane.chatId) && !active
+              ? "updated"
+              : null;
         const paneActionsLabel = t("workbench.paneActions", { title: pane.title });
         const selected = selectedDeleteKeys.has(pane.key);
         const isPinned = pinned.has(pane.key);
@@ -1852,10 +1863,27 @@ function ChatsFoldFooter({
 function SessionActivityIndicator({
   state,
 }: {
-  state: "running" | "updated" | null;
+  state: "running" | "updated" | "recovery" | null;
 }) {
   const { t } = useTranslation();
 
+  if (state === "recovery") {
+    const label = t("chat.activity.recovery", {
+      defaultValue: "This conversation needs your attention",
+    });
+    return (
+      <SidebarItemTooltip label={label}>
+        <span
+          role="img"
+          aria-label={label}
+          className="grid h-4 w-4 shrink-0 place-items-center text-[#ff8a3d]"
+        >
+          <AlertTriangle className="h-3.5 w-3.5" strokeWidth={2} aria-hidden />
+        </span>
+      </SidebarItemTooltip>
+    );
+  }
+
   if (state === "running") {
     const label = t("chat.activity.running");
     return (

webui/src/components/Sidebar.tsx

@@ -82,6 +82,7 @@ interface SidebarProps {
   collapsedGroups?: Record<string, boolean>;
   runningChatIds?: string[];
   updatedChatIds?: string[];
+  recoveryChatIds?: string[];
   viewState?: SidebarViewState;
   showArchived?: boolean;
   archivedCount?: number;
@@ -270,6 +271,7 @@ export function Sidebar(props: SidebarProps) {
             collapsedGroups={props.collapsedGroups}
             runningChatIds={props.runningChatIds}
             updatedChatIds={props.updatedChatIds}
+            recoveryChatIds={props.recoveryChatIds}
             density={props.viewState?.density}
             showPreviews={props.viewState?.show_previews}
             showTimestamps={props.viewState?.show_timestamps}

webui/src/components/settings/overview/OverviewSettings.tsx

@@ -421,6 +421,37 @@ export function AppearanceSettings({
               label={localPrefs.brandLogos ? tx("settings.values.on", "On") : tx("settings.values.off", "Off")}
             />
           </SettingsRow>
+          <SettingsRow
+            title={tx("settings.rows.browserNotifications", "Task notifications")}
+            description={tx(
+              "settings.help.browserNotifications",
+              "Notify only when this page is in the background. Off by default.",
+            )}
+          >
+            <ToggleButton
+              checked={localPrefs.browserNotifications}
+              onChange={(enabled) => {
+                if (!enabled) {
+                  onChangeLocalPrefs((prev) => ({ ...prev, browserNotifications: false }));
+                  return;
+                }
+                if (typeof Notification === "undefined") return;
+                if (Notification.permission === "granted") {
+                  onChangeLocalPrefs((prev) => ({ ...prev, browserNotifications: true }));
+                  return;
+                }
+                void Notification.requestPermission().then((permission) => {
+                  if (permission === "granted") {
+                    onChangeLocalPrefs((prev) => ({ ...prev, browserNotifications: true }));
+                  }
+                });
+              }}
+              ariaLabel={tx("settings.rows.browserNotifications", "Task notifications")}
+              label={localPrefs.browserNotifications
+                ? tx("settings.values.on", "On")
+                : tx("settings.values.off", "Off")}
+            />
+          </SettingsRow>
         </SettingsGroup>
       </section>
     </div>

webui/src/components/thread/RecoveryNotice.tsx

@@ -0,0 +1,108 @@
+import { useEffect, useState } from "react";
+import { AlertTriangle, LoaderCircle, RotateCcw, X } from "lucide-react";
+import { useTranslation } from "react-i18next";
+
+import { Button } from "@/components/ui/button";
+import { cn } from "@/lib/utils";
+import type { RecoveryState } from "@/lib/types";
+
+interface RecoveryNoticeProps {
+  state: RecoveryState;
+  onContinue: () => Promise<void>;
+  onDismiss: () => Promise<void>;
+}
+
+export function RecoveryNotice({ state, onContinue, onDismiss }: RecoveryNoticeProps) {
+  const { t } = useTranslation();
+  const [pending, setPending] = useState<"continue" | "dismiss" | null>(null);
+  const [error, setError] = useState<string | null>(null);
+  const [hiddenRecoveryId, setHiddenRecoveryId] = useState<string | null>(null);
+  useEffect(() => {
+    // A continuation can be interrupted again with the same recovery ID.
+    // Reveal the decision surface when the server returns to a waiting state.
+    if (state.status === "awaiting_user" || state.status === "failed") {
+      setHiddenRecoveryId(null);
+    }
+  }, [state.recovery_id, state.status]);
+  if (state.status === "recovered" || hiddenRecoveryId === state.recovery_id) return null;
+
+  const waiting = state.status === "awaiting_user" || state.status === "failed";
+  const contextUnavailable = state.can_continue === false;
+  const title = state.status === "failed"
+    ? t("recovery.failed", { defaultValue: "Task recovery failed" })
+    : waiting
+      ? t("recovery.interrupted", { defaultValue: "Task interrupted" })
+      : t("recovery.resuming", { defaultValue: "Restoring interrupted task…" });
+  const detail = state.status === "failed" || contextUnavailable
+    ? t("recovery.failedHelp", {
+        defaultValue: "The saved task could not be restored safely. Review it before continuing.",
+      })
+    : waiting
+      ? t("recovery.review", { defaultValue: "Review the task before continuing. Tools will not be replayed automatically." })
+      : t("recovery.safeResume", { defaultValue: "Continuing from saved conversation context." });
+  const run = (action: "continue" | "dismiss") => {
+    setPending(action);
+    setError(null);
+    // ``resuming`` is an internal transition, not another task for the user
+    // to monitor. Hide the notice optimistically and only bring it back if
+    // the explicit action is rejected.
+    if (action === "continue") setHiddenRecoveryId(state.recovery_id);
+    const operation = action === "continue" ? onContinue() : onDismiss();
+    void operation.catch(() => {
+      if (action === "continue") setHiddenRecoveryId(null);
+      setError(t("recovery.actionFailed", { defaultValue: "Recovery action failed. Try again." }));
+    }).finally(() => setPending(null));
+  };
+
+  return (
+    <div
+      role={waiting ? "alert" : "status"}
+      aria-live={waiting ? "assertive" : "polite"}
+      aria-busy={state.status === "resuming"}
+      data-recovery-status={state.status}
+      className="mx-auto mb-2 flex w-full max-w-[49.5rem] items-center gap-3 rounded-control border border-border/70 bg-muted/35 px-3 py-2 text-sm transition-[background-color,border-color,opacity,transform] duration-200 ease-out motion-reduce:transition-none animate-in fade-in-0 slide-in-from-bottom-1 duration-200 motion-reduce:animate-none"
+    >
+      {waiting ? (
+        <AlertTriangle className="h-4 w-4 shrink-0 text-amber-600 dark:text-amber-400" aria-hidden />
+      ) : (
+        <LoaderCircle className="h-4 w-4 shrink-0 animate-spin text-primary motion-reduce:animate-none" aria-hidden />
+      )}
+      <div className="min-w-0 flex-1">
+        <p className="font-medium">
+          {title}
+        </p>
+        <p className={cn(
+          "mt-0.5 text-xs",
+          error ? "text-destructive" : "text-muted-foreground",
+        )}>
+          {error ?? detail}
+        </p>
+      </div>
+      {waiting ? (
+        <div className="flex shrink-0 items-center gap-1.5">
+          <Button
+            type="button"
+            size="sm"
+            variant="outline"
+            disabled={pending !== null}
+            onClick={() => run("dismiss")}
+          >
+            <X className="mr-1 h-3.5 w-3.5" aria-hidden />
+            {t("recovery.dismiss", { defaultValue: "Dismiss" })}
+          </Button>
+          {!contextUnavailable ? (
+            <Button
+              type="button"
+              size="sm"
+              disabled={pending !== null}
+              onClick={() => run("continue")}
+            >
+              <RotateCcw className="mr-1 h-3.5 w-3.5" aria-hidden />
+              {t("recovery.continue", { defaultValue: "Continue" })}
+            </Button>
+          ) : null}
+        </div>
+      ) : null}
+    </div>
+  );
+}

webui/src/components/thread/ThreadShell.tsx

@@ -7,6 +7,7 @@ import { FilePreviewAvailabilityProvider } from "@/components/FilePreviewAvailab
 import { FilePreviewPanel } from "@/components/FilePreviewPanel";
 import { SessionHandleLabel } from "@/components/SessionHandleLabel";
 import { PromptNavigator } from "@/components/thread/PromptNavigator";
+import { RecoveryNotice } from "@/components/thread/RecoveryNotice";
 import { SessionInfoPopover } from "@/components/thread/SessionInfoPopover";
 import {
   ThreadComposer,
@@ -763,6 +764,9 @@ export function ThreadShell({
     isStreaming,
     runStartedAt,
     goalState,
+    recoveryState,
+    continueRecovery,
+    dismissRecovery,
     send,
     transcribeAudio,
     stop,
@@ -835,8 +839,15 @@ export function ThreadShell({
     [displayMessages],
   );
   const currentGoalState = messagesReady ? goalState : undefined;
-  const currentRunStartedAt = messagesReady ? runStartedAt : null;
-  const turnActive = messagesReady && (isStreaming || currentRunStartedAt !== null);
+  // Decision states freeze the interrupted turn and hand the next action to
+  // the recovery notice. ``resuming`` remains active; ``recovered`` is only
+  // historical metadata and must not suppress a later normal turn.
+  const recoveryNeedsDecision = recoveryState?.status === "awaiting_user"
+    || recoveryState?.status === "failed";
+  const currentRunStartedAt = messagesReady && !recoveryNeedsDecision ? runStartedAt : null;
+  const turnActive = messagesReady
+    && !recoveryNeedsDecision
+    && (isStreaming || currentRunStartedAt !== null);
   const restoredViewportTurnId = useMemo(
     () => turnActive ? latestActiveTurnId(displayMessages, currentRunStartedAt) : null,
     [currentRunStartedAt, displayMessages, turnActive],
@@ -1472,6 +1483,13 @@ export function ThreadShell({
 
   const composer = (
     <>
+      {recoveryState ? (
+        <RecoveryNotice
+          state={recoveryState}
+          onContinue={continueRecovery}
+          onDismiss={dismissRecovery}
+        />
+      ) : null}
       {streamError && !hasInlineDeliveryError(messages, streamError) ? (
         <StreamErrorNotice
           error={streamError}

webui/src/hooks/useNanobotStream.ts

@@ -1,4 +1,5 @@
 import { useCallback, useEffect, useRef, useState } from "react";
+import { useTranslation } from "react-i18next";
 
 import { useClient } from "@/providers/ClientProvider";
 import { toMediaAttachment } from "@/lib/media";
@@ -28,6 +29,7 @@ import {
 } from "@/lib/thread-event-projection";
 import type { UIMessageTurnFields } from "@/lib/thread-event-projection";
 import { formatQuotedUserMessage } from "@/lib/user-message-quote";
+import { readLocalPreferences } from "@/lib/local-preferences";
 import type {
   InboundEvent,
   OutboundCliAppMention,
@@ -36,6 +38,7 @@ import type {
   SessionMention,
   GoalStateWsPayload,
   MessageDeliveryStatus,
+  RecoveryState,
   UIMediaAttachment,
   UIMessage,
   WorkspaceScopePayload,
@@ -244,6 +247,9 @@ export function useNanobotStream(
   runStartedAt: number | null;
   /** Latest sustained goal for this ``chatId`` (``goal_state`` WS events). */
   goalState: GoalStateWsPayload | undefined;
+  recoveryState: RecoveryState | null;
+  continueRecovery: () => Promise<void>;
+  dismissRecovery: () => Promise<void>;
   send: (
     content: string,
     images?: SendAttachment[],
@@ -262,6 +268,7 @@ export function useNanobotStream(
   dismissStreamError: () => void;
 } {
   const { client } = useClient();
+  const { t } = useTranslation();
   const initialRunStartedAt = chatId ? client.getRunStartedAt(chatId) : null;
   const [messages, setMessages] = useState<UIMessage[]>(initialMessages);
   const [messageOwnerChatId, setMessageOwnerChatId] = useState(chatId);
@@ -273,6 +280,7 @@ export function useNanobotStream(
   /** Unix epoch seconds when the current user turn started; cleared on ``idle``. */
   const [runStartedAt, setRunStartedAt] = useState<number | null>(initialRunStartedAt);
   const [goalState, setGoalState] = useState<GoalStateWsPayload | undefined>(undefined);
+  const [recoveryState, setRecoveryState] = useState<RecoveryState | null>(null);
   const [streamError, setStreamError] = useState<StreamError | null>(null);
   const buffer = useRef<StreamBuffer | null>(null);
   const activeAssistantRef = useRef<ActiveAssistantCursor | null>(null);
@@ -288,6 +296,16 @@ export function useNanobotStream(
 
   const dismissStreamError = useCallback(() => setStreamError(null), []);
 
+  const notifyInBackground = useCallback((body: string) => {
+    if (
+      typeof Notification === "undefined"
+      || Notification.permission !== "granted"
+      || document.visibilityState === "visible"
+      || !readLocalPreferences().browserNotifications
+    ) return;
+    new Notification("nanobot", { body });
+  }, []);
+
   const clearPendingStreamWork = useCallback(() => {
     if (streamFrameRef.current !== null) {
       window.cancelAnimationFrame(streamFrameRef.current);
@@ -639,6 +657,7 @@ export function useNanobotStream(
     setStreamError(null);
     setRunStartedAt(restoredRunStartedAt);
     setGoalState(chatId ? client.getGoalState(chatId) : undefined);
+    setRecoveryState(null);
     buffer.current = null;
     activeAssistantRef.current = null;
     closedAssistantStreamIdsRef.current.clear();
@@ -846,10 +865,71 @@ export function useNanobotStream(
           return finalized;
         });
         suppressStreamUntilTurnEndRef.current = false;
+        notifyInBackground(t("recovery.completed", { defaultValue: "Task completed" }));
         onTurnEnd?.();
         return;
       }
 
+      if (ev.event === "recovery_state") {
+        const next: RecoveryState = {
+          status: ev.status,
+          recovery_id: ev.recovery_id,
+          ...(ev.reason ? { reason: ev.reason } : {}),
+          ...(typeof ev.attempts === "number" ? { attempts: ev.attempts } : {}),
+          ...(typeof ev.can_continue === "boolean"
+            ? { can_continue: ev.can_continue }
+            : {}),
+        };
+        setRecoveryState(next);
+        if (ev.status === "resuming") {
+          setRunStartedAt((current) => current ?? Date.now() / 1000);
+          setIsStreaming(true);
+        }
+        if (
+          ev.status === "awaiting_user"
+          || ev.status === "recovered"
+          || ev.status === "failed"
+        ) {
+          // Recovery is an explicit boundary. The interrupted turn is no
+          // longer running, so do not let the stale start time keep the
+          // activity clock (or composer stop state) alive underneath the
+          // recovery notice.
+          setRunStartedAt(null);
+          setIsStreaming(false);
+          client.finishRunLocally(chatId);
+          clearPendingStreamWork();
+          closeActiveAssistantStream();
+          clearActivitySegment();
+          if (ev.status !== "recovered") {
+            notifyInBackground(
+              ev.status === "failed"
+                ? t("recovery.failed", { defaultValue: "Task recovery failed" })
+                : t("recovery.interrupted", { defaultValue: "Task interrupted" }),
+            );
+          }
+        }
+        return;
+      }
+
+      if (ev.event === "attached") {
+        setRecoveryState(ev.recovery_state ?? null);
+        if (ev.recovery_state?.status === "resuming") {
+          setRunStartedAt((current) => current ?? Date.now() / 1000);
+          setIsStreaming(true);
+        } else if (
+          ev.recovery_state?.status === "awaiting_user"
+          || ev.recovery_state?.status === "failed"
+        ) {
+          setRunStartedAt(null);
+          setIsStreaming(false);
+          client.finishRunLocally(chatId);
+          clearPendingStreamWork();
+          closeActiveAssistantStream();
+          clearActivitySegment();
+        }
+        return;
+      }
+
       if (ev.event === "message") {
         if (
           suppressStreamUntilTurnEndRef.current &&
@@ -1062,8 +1142,10 @@ export function useNanobotStream(
     ensureActivitySegmentId,
     flushPendingStreamEvents,
     isSideChannelEvent,
+    notifyInBackground,
     onTurnEnd,
     schedulePendingStreamFlush,
+    t,
   ]);
 
   const send = useCallback(
@@ -1173,12 +1255,32 @@ export function useNanobotStream(
     [client],
   );
 
+  const recoveryAction = useCallback(async (action: "continue" | "dismiss") => {
+    if (!chatId || !recoveryState) return;
+    await client.requestMutation(`recovery.${action}`, {
+      chat_id: chatId,
+      recovery_id: recoveryState.recovery_id,
+    });
+  }, [chatId, client, recoveryState]);
+
+  const continueRecovery = useCallback(
+    () => recoveryAction("continue"),
+    [recoveryAction],
+  );
+  const dismissRecovery = useCallback(
+    () => recoveryAction("dismiss"),
+    [recoveryAction],
+  );
+
   return {
     messages,
     messagesReady: messageOwnerChatId === chatId,
     isStreaming,
     runStartedAt,
     goalState,
+    recoveryState,
+    continueRecovery,
+    dismissRecovery,
     send,
     transcribeAudio,
     stop,

webui/src/i18n/locales/en/common.json

@@ -198,6 +198,7 @@
       "fileEditDisplay": "File edit display",
       "codeWrap": "Code wrapping",
       "brandLogos": "Brand logos",
+      "browserNotifications": "Task notifications",
       "maxResults": "Max results",
       "timeout": "Timeout",
       "jinaReader": "Jina reader",
@@ -243,6 +244,7 @@
       "fileEditDisplay": "Choose whether file edit activity opens as line counts or a diff.",
       "codeWrap": "Keep long code lines readable on smaller screens.",
       "brandLogos": "Show third-party provider and CLI logos in Settings.",
+      "browserNotifications": "Notify only when this page is in the background. Off by default.",
       "maxResults": "Results returned by each web_search call.",
       "timeout": "Seconds before a search provider request times out.",
       "jinaReader": "Use Jina Reader for web_fetch when available.",
@@ -1013,7 +1015,8 @@
     "activity": {
       "running": "Agent running",
       "complete": "Agent finished",
-      "updated": "New activity"
+      "updated": "New activity",
+      "recovery": "This conversation needs your attention"
     },
     "pin": "Pin",
     "unpin": "Unpin",
@@ -1436,6 +1439,18 @@
       "estimated": "Includes estimated usage"
     }
   },
+  "recovery": {
+    "actionFailed": "Recovery action failed. Try again.",
+    "interrupted": "Task interrupted",
+    "completed": "Task completed",
+    "failed": "Task recovery failed",
+    "failedHelp": "The saved task could not be restored safely. Review it before continuing.",
+    "resuming": "Restoring interrupted task…",
+    "review": "Review the task before continuing. Tools will not be replayed automatically.",
+    "safeResume": "Continuing from saved conversation context.",
+    "dismiss": "Dismiss",
+    "continue": "Continue"
+  },
   "lightbox": {
     "title": "Image preview",
     "open": "View image",

webui/src/i18n/locales/es/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "Acceso predeterminado",
       "currentModel": "Configuración actual",
       "brandLogos": "Logos de marca",
+      "browserNotifications": "Notificaciones de tareas",
       "cliAppsCatalog": "Catálogo",
       "cliAppsFilter": "Filtro",
       "engine": "Motor",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "Definido por el modelo seleccionado.",
       "selectedModelValue": "Definido por el modelo seleccionado.",
       "brandLogos": "Muestra logos de proveedores de terceros y CLI en Ajustes.",
+      "browserNotifications": "Notifica solo cuando esta página está en segundo plano. Desactivado de forma predeterminada.",
       "cliAppsCatalog": "Instala solo adaptadores CLI de aplicaciones que nanobot puede ejecutar localmente; las aplicaciones nativas no se modifican.",
       "cliAppsFilter": "Busca por aplicación, categoría o capacidad.",
       "logs": "Abre la carpeta de registros del motor nativo.",
@@ -1000,7 +1002,8 @@
     "activity": {
       "running": "Agente en ejecución",
       "complete": "Agente terminado",
-      "updated": "Nueva actividad"
+      "updated": "Nueva actividad",
+      "recovery": "Esta conversación requiere tu atención"
     },
     "pin": "Fijar",
     "unpin": "Desfijar",
@@ -1423,6 +1426,18 @@
     "automationSourceFallback": "Automatización",
     "automationTriggered": "Activada automáticamente"
   },
+  "recovery": {
+    "actionFailed": "La recuperación falló. Inténtalo de nuevo.",
+    "interrupted": "Tarea interrumpida",
+    "completed": "Tarea completada",
+    "failed": "La recuperación de la tarea falló",
+    "failedHelp": "La tarea guardada no se pudo restaurar de forma segura. Revísala antes de continuar.",
+    "resuming": "Restaurando la tarea interrumpida…",
+    "review": "Revisa la tarea antes de continuar. Las herramientas no se repetirán automáticamente.",
+    "safeResume": "Continuando desde el contexto guardado de la conversación.",
+    "dismiss": "Descartar",
+    "continue": "Continuar"
+  },
   "lightbox": {
     "title": "Vista previa de imagen",
     "open": "Ver imagen",

webui/src/i18n/locales/fr/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "Accès par défaut",
       "currentModel": "Configuration actuelle",
       "brandLogos": "Logos de marque",
+      "browserNotifications": "Notifications de tâches",
       "cliAppsCatalog": "Catalogue",
       "cliAppsFilter": "Filtre",
       "engine": "Moteur",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "Défini par le modèle sélectionné.",
       "selectedModelValue": "Défini par le modèle sélectionné.",
       "brandLogos": "Affiche les logos de fournisseurs tiers et CLI dans les Réglages.",
+      "browserNotifications": "Notifier uniquement lorsque cette page est en arrière-plan. Désactivé par défaut.",
       "cliAppsCatalog": "Installe uniquement les adaptateurs CLI d’applications que nanobot peut exécuter localement ; les applications natives restent inchangées.",
       "cliAppsFilter": "Recherchez par application, catégorie ou capacité.",
       "logs": "Ouvre le dossier des journaux du moteur natif.",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "Agent en cours",
       "complete": "Agent terminé",
-      "updated": "Nouvelle activité"
+      "updated": "Nouvelle activité",
+      "recovery": "Cette conversation nécessite votre attention"
     },
     "pin": "Épingler",
     "unpin": "Désépingler",
@@ -1422,6 +1425,18 @@
     "automationSourceFallback": "Automatisation",
     "automationTriggered": "Déclenché automatiquement"
   },
+  "recovery": {
+    "actionFailed": "La récupération a échoué. Réessayez.",
+    "interrupted": "Tâche interrompue",
+    "completed": "Tâche terminée",
+    "failed": "Échec de la récupération de la tâche",
+    "failedHelp": "La tâche enregistrée n’a pas pu être restaurée en toute sécurité. Vérifiez-la avant de continuer.",
+    "resuming": "Restauration de la tâche interrompue…",
+    "review": "Vérifiez la tâche avant de continuer. Les outils ne seront pas relancés automatiquement.",
+    "safeResume": "Reprise depuis le contexte de conversation enregistré.",
+    "dismiss": "Ignorer",
+    "continue": "Continuer"
+  },
   "lightbox": {
     "title": "Aperçu de l’image",
     "open": "Voir l’image",

webui/src/i18n/locales/id/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "Akses bawaan",
       "currentModel": "Konfigurasi saat ini",
       "brandLogos": "Logo merek",
+      "browserNotifications": "Notifikasi tugas",
       "cliAppsCatalog": "Katalog",
       "cliAppsFilter": "Saring",
       "engine": "Mesin",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "Ditentukan oleh model yang dipilih.",
       "selectedModelValue": "Ditentukan oleh model yang dipilih.",
       "brandLogos": "Tampilkan logo penyedia pihak ketiga dan CLI di Pengaturan.",
+      "browserNotifications": "Beri tahu hanya saat halaman ini di latar belakang. Nonaktif secara bawaan.",
       "cliAppsCatalog": "Instal hanya adaptor CLI aplikasi yang dapat dijalankan nanobot secara lokal; aplikasi asli tidak diubah.",
       "cliAppsFilter": "Cari berdasarkan aplikasi, kategori, atau kemampuan.",
       "logs": "Buka folder log mesin asli.",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "Agen sedang berjalan",
       "complete": "Agen selesai",
-      "updated": "Aktivitas baru"
+      "updated": "Aktivitas baru",
+      "recovery": "Percakapan ini memerlukan perhatian Anda"
     },
     "pin": "Sematkan",
     "unpin": "Lepas sematan",
@@ -1422,6 +1425,18 @@
     "automationSourceFallback": "Otomatisasi",
     "automationTriggered": "Dipicu otomatis"
   },
+  "recovery": {
+    "actionFailed": "Pemulihan gagal. Coba lagi.",
+    "interrupted": "Tugas terputus",
+    "completed": "Tugas selesai",
+    "failed": "Pemulihan tugas gagal",
+    "failedHelp": "Tugas tersimpan tidak dapat dipulihkan dengan aman. Tinjau sebelum melanjutkan.",
+    "resuming": "Memulihkan tugas yang terputus…",
+    "review": "Tinjau tugas sebelum melanjutkan. Alat tidak akan dijalankan ulang secara otomatis.",
+    "safeResume": "Melanjutkan dari konteks percakapan yang tersimpan.",
+    "dismiss": "Abaikan",
+    "continue": "Lanjutkan"
+  },
   "lightbox": {
     "title": "Pratinjau gambar",
     "open": "Lihat gambar",

webui/src/i18n/locales/ja/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "既定の権限",
       "currentModel": "現在の設定",
       "brandLogos": "ブランドロゴ",
+      "browserNotifications": "タスク通知",
       "cliAppsCatalog": "カタログ",
       "cliAppsFilter": "フィルター",
       "engine": "エンジン",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "選択したモデルによって設定されます。",
       "selectedModelValue": "選択したモデルによって設定されます。",
       "brandLogos": "設定で第三者プロバイダーと CLI のロゴを表示します。",
+      "browserNotifications": "このページがバックグラウンドにある場合のみ通知します。既定ではオフです。",
       "cliAppsCatalog": "nanobot がローカルで実行できるアプリ CLI アダプターだけをインストールします。ネイティブアプリは変更しません。",
       "cliAppsFilter": "アプリ、カテゴリ、機能で検索します。",
       "logs": "ネイティブエンジンのログフォルダーを開きます。",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "エージェント実行中",
       "complete": "エージェント完了",
-      "updated": "新しいアクティビティ"
+      "updated": "新しいアクティビティ",
+      "recovery": "この会話には対応が必要です"
     },
     "pin": "ピン留め",
     "unpin": "ピン留めを解除",
@@ -1422,6 +1425,18 @@
     "automationSourceFallback": "自動化",
     "automationTriggered": "自動実行"
   },
+  "recovery": {
+    "actionFailed": "復元操作に失敗しました。もう一度お試しください。",
+    "interrupted": "タスクが中断されました",
+    "completed": "タスクが完了しました",
+    "failed": "タスクの復元に失敗しました",
+    "failedHelp": "保存されたタスクを安全に復元できませんでした。続行前に確認してください。",
+    "resuming": "中断されたタスクを復元しています…",
+    "review": "続行する前にタスクを確認してください。ツールは自動的に再実行されません。",
+    "safeResume": "保存された会話コンテキストから続行しています。",
+    "dismiss": "閉じる",
+    "continue": "続行"
+  },
   "lightbox": {
     "title": "画像プレビュー",
     "open": "画像を表示",

webui/src/i18n/locales/ko/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "기본 권한",
       "currentModel": "현재 구성",
       "brandLogos": "브랜드 로고",
+      "browserNotifications": "작업 알림",
       "cliAppsCatalog": "카탈로그",
       "cliAppsFilter": "필터",
       "engine": "엔진",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "선택한 모델에 의해 설정됩니다.",
       "selectedModelValue": "선택한 모델에 의해 설정됩니다.",
       "brandLogos": "설정에서 타사 제공자와 CLI 로고를 표시합니다.",
+      "browserNotifications": "이 페이지가 백그라운드에 있을 때만 알립니다. 기본값은 꺼짐입니다.",
       "cliAppsCatalog": "nanobot이 로컬에서 실행할 수 있는 앱 CLI 어댑터만 설치합니다. 네이티브 앱은 변경하지 않습니다.",
       "cliAppsFilter": "앱, 카테고리 또는 기능으로 검색합니다.",
       "logs": "네이티브 엔진 로그 폴더를 엽니다.",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "에이전트 실행 중",
       "complete": "에이전트 완료",
-      "updated": "새 활동"
+      "updated": "새 활동",
+      "recovery": "이 대화에는 확인이 필요합니다"
     },
     "pin": "고정",
     "unpin": "고정 해제",
@@ -1422,6 +1425,18 @@
     "automationSourceFallback": "자동화",
     "automationTriggered": "자동 실행됨"
   },
+  "recovery": {
+    "actionFailed": "복구 작업에 실패했습니다. 다시 시도하세요.",
+    "interrupted": "작업이 중단됨",
+    "completed": "작업 완료",
+    "failed": "작업 복구 실패",
+    "failedHelp": "저장된 작업을 안전하게 복구할 수 없습니다. 계속하기 전에 검토하세요.",
+    "resuming": "중단된 작업을 복구하는 중…",
+    "review": "계속하기 전에 작업을 검토하세요. 도구는 자동으로 다시 실행되지 않습니다.",
+    "safeResume": "저장된 대화 컨텍스트에서 계속합니다.",
+    "dismiss": "닫기",
+    "continue": "계속"
+  },
   "lightbox": {
     "title": "이미지 미리보기",
     "open": "이미지 보기",

webui/src/i18n/locales/pt-BR/common.json

@@ -198,6 +198,7 @@
       "fileEditDisplay": "Exibição de edição de arquivo",
       "codeWrap": "Quebra de linha no código",
       "brandLogos": "Logos de marca",
+      "browserNotifications": "Notificações de tarefas",
       "maxResults": "Máx. de resultados",
       "timeout": "Tempo limite",
       "jinaReader": "Leitor Jina",
@@ -243,6 +244,7 @@
       "fileEditDisplay": "Escolha se a atividade de edição de arquivo é exibida como contagem de linhas ou como diferenças.",
       "codeWrap": "Mantém linhas longas de código legíveis em telas menores.",
       "brandLogos": "Mostra logotipos de provedores terceiros e de CLIs em Configurações.",
+      "browserNotifications": "Notifica somente quando esta página está em segundo plano. Desativado por padrão.",
       "maxResults": "Resultados retornados por cada chamada de web_search.",
       "timeout": "Segundos antes de uma requisição de busca expirar.",
       "jinaReader": "Usa o Jina Reader para web_fetch quando disponível.",
@@ -1013,7 +1015,8 @@
     "activity": {
       "running": "Agente em execução",
       "complete": "Agente finalizado",
-      "updated": "Nova atividade"
+      "updated": "Nova atividade",
+      "recovery": "Esta conversa precisa da sua atenção"
     },
     "pin": "Fixar",
     "unpin": "Desafixar",
@@ -1436,6 +1439,18 @@
       "estimated": "Inclui uso estimado"
     }
   },
+  "recovery": {
+    "actionFailed": "A recuperação falhou. Tente novamente.",
+    "interrupted": "Tarefa interrompida",
+    "completed": "Tarefa concluída",
+    "failed": "Falha ao recuperar a tarefa",
+    "failedHelp": "Não foi possível restaurar a tarefa salva com segurança. Revise-a antes de continuar.",
+    "resuming": "Restaurando a tarefa interrompida…",
+    "review": "Revise a tarefa antes de continuar. As ferramentas não serão executadas novamente de forma automática.",
+    "safeResume": "Continuando a partir do contexto de conversa salvo.",
+    "dismiss": "Descartar",
+    "continue": "Continuar"
+  },
   "lightbox": {
     "title": "Pré-visualização de imagem",
     "open": "Ver imagem",

webui/src/i18n/locales/vi/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "Quyền mặc định",
       "currentModel": "Cấu hình hiện tại",
       "brandLogos": "Logo thương hiệu",
+      "browserNotifications": "Thông báo tác vụ",
       "cliAppsCatalog": "Danh mục",
       "cliAppsFilter": "Bộ lọc",
       "engine": "Bộ máy",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "Được đặt bởi mô hình đã chọn.",
       "selectedModelValue": "Được đặt bởi mô hình đã chọn.",
       "brandLogos": "Hiển thị logo nhà cung cấp bên thứ ba và CLI trong Cài đặt.",
+      "browserNotifications": "Chỉ thông báo khi trang này ở nền. Mặc định tắt.",
       "cliAppsCatalog": "Chỉ cài đặt các bộ chuyển đổi CLI ứng dụng mà nanobot có thể chạy cục bộ; ứng dụng gốc không bị thay đổi.",
       "cliAppsFilter": "Tìm theo ứng dụng, danh mục hoặc khả năng.",
       "logs": "Mở thư mục nhật ký của bộ máy gốc.",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "Tác nhân đang chạy",
       "complete": "Tác nhân đã hoàn tất",
-      "updated": "Hoạt động mới"
+      "updated": "Hoạt động mới",
+      "recovery": "Cuộc trò chuyện này cần bạn xử lý"
     },
     "pin": "Ghim",
     "unpin": "Bỏ ghim",
@@ -1422,6 +1425,18 @@
     "automationSourceFallback": "Tự động hóa",
     "automationTriggered": "Tự động kích hoạt"
   },
+  "recovery": {
+    "actionFailed": "Khôi phục thất bại. Hãy thử lại.",
+    "interrupted": "Tác vụ bị gián đoạn",
+    "completed": "Tác vụ đã hoàn tất",
+    "failed": "Khôi phục tác vụ thất bại",
+    "failedHelp": "Không thể khôi phục an toàn tác vụ đã lưu. Hãy xem lại trước khi tiếp tục.",
+    "resuming": "Đang khôi phục tác vụ bị gián đoạn…",
+    "review": "Hãy xem lại tác vụ trước khi tiếp tục. Công cụ sẽ không tự động chạy lại.",
+    "safeResume": "Đang tiếp tục từ ngữ cảnh hội thoại đã lưu.",
+    "dismiss": "Bỏ qua",
+    "continue": "Tiếp tục"
+  },
   "lightbox": {
     "title": "Xem trước ảnh",
     "open": "Xem ảnh",

webui/src/i18n/locales/zh-CN/common.json

@@ -198,6 +198,7 @@
       "fileEditDisplay": "文件编辑显示",
       "codeWrap": "代码换行",
       "brandLogos": "品牌 Logo",
+      "browserNotifications": "任务通知",
       "maxResults": "最大结果数",
       "timeout": "超时",
       "jinaReader": "Jina 阅读器",
@@ -243,6 +244,7 @@
       "fileEditDisplay": "选择文件编辑活动默认显示行数还是差异。",
       "codeWrap": "让长代码行在小屏幕上也易读。",
       "brandLogos": "在设置中显示第三方提供商和 CLI 图标。",
+      "browserNotifications": "仅在页面位于后台时通知，默认关闭。",
       "maxResults": "每次 web_search 调用返回的结果数。",
       "timeout": "搜索提供商请求超时前等待的秒数。",
       "jinaReader": "可用时为 web_fetch 使用 Jina Reader。",
@@ -1013,7 +1015,8 @@
     "activity": {
       "running": "智能体正在运行",
       "complete": "智能体已完成",
-      "updated": "有新内容"
+      "updated": "有新内容",
+      "recovery": "此对话需要你的处理"
     },
     "pin": "置顶",
     "unpin": "取消置顶",
@@ -1436,6 +1439,18 @@
       "estimated": "包含估算用量"
     }
   },
+  "recovery": {
+    "actionFailed": "恢复操作失败，请重试。",
+    "interrupted": "任务已中断",
+    "completed": "任务已完成",
+    "failed": "任务恢复失败",
+    "failedHelp": "无法安全恢复已保存的任务，继续前请先检查。",
+    "resuming": "正在恢复中断的任务…",
+    "review": "继续前请检查任务。工具不会被自动重放。",
+    "safeResume": "正在从已保存的对话上下文继续。",
+    "dismiss": "忽略",
+    "continue": "继续"
+  },
   "lightbox": {
     "title": "图片预览",
     "open": "查看图片",

webui/src/i18n/locales/zh-TW/common.json

@@ -161,6 +161,7 @@
       "webuiDefaultAccess": "預設存取權",
       "currentModel": "目前設定",
       "brandLogos": "品牌 Logo",
+      "browserNotifications": "任務通知",
       "cliAppsCatalog": "目錄",
       "cliAppsFilter": "篩選",
       "engine": "引擎",
@@ -204,6 +205,7 @@
       "selectedModelProvider": "由選取的模型決定。",
       "selectedModelValue": "由選取的模型決定。",
       "brandLogos": "在設定中顯示第三方供應商與 CLI 圖示。",
+      "browserNotifications": "僅在頁面位於背景時通知，預設關閉。",
       "cliAppsCatalog": "只安裝 nanobot 可在本機執行的應用程式專用 CLI 轉接器；不會改動原生應用程式。",
       "cliAppsFilter": "依應用程式、類別或功能搜尋。",
       "logs": "開啟原生引擎日誌資料夾。",
@@ -999,7 +1001,8 @@
     "activity": {
       "running": "智能體正在執行",
       "complete": "智能體已完成",
-      "updated": "有新內容"
+      "updated": "有新內容",
+      "recovery": "此對話需要你的處理"
     },
     "pin": "置頂",
     "unpin": "取消置頂",
@@ -1422,6 +1425,18 @@
     "automationTriggered": "已自動觸發",
     "askAboutSelection": "繼續提問"
   },
+  "recovery": {
+    "actionFailed": "復原操作失敗，請再試一次。",
+    "interrupted": "任務已中斷",
+    "completed": "任務已完成",
+    "failed": "任務復原失敗",
+    "failedHelp": "無法安全復原已儲存的任務，繼續前請先檢查。",
+    "resuming": "正在復原中斷的任務…",
+    "review": "繼續前請檢查任務。工具不會自動重播。",
+    "safeResume": "正在從已儲存的對話上下文繼續。",
+    "dismiss": "略過",
+    "continue": "繼續"
+  },
   "lightbox": {
     "title": "圖片預覽",
     "open": "檢視圖片",

webui/src/lib/api.ts

@@ -22,6 +22,7 @@ import type {
   ProviderOAuthCompletionResult,
   ProviderOAuthLoginResult,
   ProviderSettingsUpdate,
+  RecoveryState,
   SessionDeleteResult,
   SessionHandle,
   SessionAutomationsPayload,
@@ -192,6 +193,7 @@ export async function listSessions(
     preview?: string;
     model_preset?: string | null;
     run_started_at?: number | null;
+    recovery_state?: RecoveryState | null;
     workspace_scope?: WorkspaceScopePayload | null;
     handle?: SessionHandle | null;
   };
@@ -212,6 +214,7 @@ export async function listSessions(
       preview: s.preview ?? "",
       modelPreset: s.model_preset ?? null,
       runStartedAt: s.run_started_at ?? null,
+      recoveryState: s.recovery_state ?? null,
       workspaceScope: s.workspace_scope ?? null,
       handle,
     };

webui/src/lib/local-preferences.ts

@@ -7,6 +7,7 @@ export interface LocalPreferences {
   activityMode: LocalActivityMode;
   codeWrap: boolean;
   brandLogos: boolean;
+  browserNotifications: boolean;
   fileEditDisplayMode: FileEditDisplayMode;
 }
 
@@ -18,6 +19,7 @@ export const DEFAULT_LOCAL_PREFS: LocalPreferences = {
   activityMode: "auto",
   codeWrap: true,
   brandLogos: false,
+  browserNotifications: false,
   fileEditDisplayMode: "summary",
 };
 
@@ -35,6 +37,7 @@ export function readLocalPreferences(): LocalPreferences {
       activityMode: parsed.activityMode === "expanded" ? "expanded" : "auto",
       codeWrap: parsed.codeWrap !== false,
       brandLogos: parsed.brandLogos === true,
+      browserNotifications: parsed.browserNotifications === true,
       fileEditDisplayMode: normalizeFileEditDisplayMode(parsed.fileEditDisplayMode),
     };
   } catch {

webui/src/lib/types.ts

@@ -49,6 +49,16 @@ export interface TurnUsage {
   [key: string]: number | undefined;
 }
 
+export type RecoveryStatus = "resuming" | "awaiting_user" | "recovered" | "failed";
+
+export interface RecoveryState {
+  status: RecoveryStatus;
+  recovery_id: string;
+  reason?: string;
+  attempts?: number;
+  can_continue?: boolean;
+}
+
 export interface UIMessage {
   id: string;
   role: Role;
@@ -368,6 +378,8 @@ export interface ChatSummary {
   modelPreset?: string | null;
   /** Unix epoch seconds when this session currently has a turn in flight. */
   runStartedAt?: number | null;
+  /** Durable recovery state that needs attention after an interrupted turn. */
+  recoveryState?: RecoveryState | null;
   workspaceScope?: WorkspaceScopePayload | null;
   /** Stable, server-owned @handle for this session. */
   handle?: SessionHandle | null;
@@ -1246,6 +1258,7 @@ export type InboundEvent =
       event: "attached";
       chat_id: string;
       temporary?: boolean;
+      recovery_state?: RecoveryState;
       usage?: TurnUsage;
     }
   | {
@@ -1289,6 +1302,10 @@ export type InboundEvent =
       /** Optional structured payload on progress frames (channel-specific). */
       agent_ui?: AgentUIBlob;
     } & InboundTurnMetadata)
+  | ({
+      event: "recovery_state";
+      chat_id: string;
+    } & RecoveryState)
   | ({
       event: "file_edit";
       chat_id: string;

webui/src/tests/chat-list.test.tsx

@@ -103,6 +103,24 @@ describe("ChatList", () => {
     );
   });
 
+  it("marks a conversation that needs recovery attention with a warning indicator", () => {
+    render(
+      <ChatList
+        sessions={[session({ chatId: "recovery", title: "Interrupted task" })]}
+        recoveryChatIds={["recovery"]}
+        activeKey="websocket:other"
+        onSelect={vi.fn()}
+        onRequestDelete={vi.fn()}
+        onTogglePin={vi.fn()}
+        onRequestRename={vi.fn()}
+        onToggleArchive={vi.fn()}
+      />,
+    );
+
+    expect(screen.getByRole("img", { name: "This conversation needs your attention" }))
+      .toBeInTheDocument();
+  });
+
   it("keeps handle columns intact inside grouped panes", () => {
     render(
       <ChatList
@@ -151,6 +169,26 @@ describe("ChatList", () => {
     }
   });
 
+  it("shows the running indicator while a recovery continuation is active", () => {
+    render(
+      <ChatList
+        sessions={[session({ chatId: "recovery", title: "Interrupted task" })]}
+        runningChatIds={["recovery"]}
+        recoveryChatIds={["recovery"]}
+        activeKey="websocket:other"
+        onSelect={vi.fn()}
+        onRequestDelete={vi.fn()}
+        onTogglePin={vi.fn()}
+        onRequestRename={vi.fn()}
+        onToggleArchive={vi.fn()}
+      />,
+    );
+
+    expect(screen.getByRole("img", { name: "Agent running" })).toBeInTheDocument();
+    expect(screen.queryByRole("img", { name: "This conversation needs your attention" }))
+      .not.toBeInTheDocument();
+  });
+
   it("keeps tab grouping out of drag protocols while exposing inactive panes as mention sources", () => {
     render(
       <ChatList

webui/src/tests/i18n.test.tsx

@@ -161,6 +161,7 @@ const LOCALIZED_SETTINGS_COPY_KEYS = [
   "settings.rows.fileEditDisplay",
   "settings.rows.codeWrap",
   "settings.rows.brandLogos",
+  "settings.rows.browserNotifications",
   "settings.rows.currentModel",
   "settings.rows.localServiceAccess",
   "settings.rows.webuiDefaultAccess",
@@ -172,6 +173,7 @@ const LOCALIZED_SETTINGS_COPY_KEYS = [
   "settings.help.fileEditDisplay",
   "settings.help.codeWrap",
   "settings.help.brandLogos",
+  "settings.help.browserNotifications",
   "settings.help.currentModel",
   "settings.help.localServiceAccess",
   "settings.help.webuiDefaultAccess",
@@ -252,6 +254,7 @@ const LOCALIZED_NEW_SURFACE_KEYS = [
   "chat.activity.running",
   "chat.activity.complete",
   "chat.activity.updated",
+  "chat.activity.recovery",
   "chat.pin",
   "chat.unpin",
   "chat.rename",
@@ -293,6 +296,16 @@ const LOCALIZED_NEW_SURFACE_KEYS = [
   "message.skill",
   "settings.channels.connectionChecks",
   "settings.channels.open",
+  "recovery.actionFailed",
+  "recovery.interrupted",
+  "recovery.completed",
+  "recovery.failed",
+  "recovery.failedHelp",
+  "recovery.resuming",
+  "recovery.review",
+  "recovery.safeResume",
+  "recovery.dismiss",
+  "recovery.continue",
 ];
 const ACCIDENTALLY_SPANISH_SETTINGS_KEYS = [
   "settings.help.provider",

webui/src/tests/local-preferences.test.ts

@@ -0,0 +1,19 @@
+import { beforeEach, describe, expect, it } from "vitest";
+
+import {
+  DEFAULT_LOCAL_PREFS,
+  readLocalPreferences,
+  writeLocalPreferences,
+} from "@/lib/local-preferences";
+
+describe("local preferences", () => {
+  beforeEach(() => localStorage.clear());
+
+  it("keeps browser notifications opt-in", () => {
+    expect(DEFAULT_LOCAL_PREFS.browserNotifications).toBe(false);
+    expect(readLocalPreferences().browserNotifications).toBe(false);
+
+    writeLocalPreferences({ ...DEFAULT_LOCAL_PREFS, browserNotifications: true });
+    expect(readLocalPreferences().browserNotifications).toBe(true);
+  });
+});

webui/src/tests/recovery-notice.test.tsx

@@ -0,0 +1,114 @@
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { describe, expect, it, vi } from "vitest";
+
+import { RecoveryNotice } from "@/components/thread/RecoveryNotice";
+
+const INTERRUPTED = {
+  status: "awaiting_user" as const,
+  recovery_id: "recovery-1",
+  reason: "tool_state_uncertain",
+};
+
+describe("RecoveryNotice", () => {
+  it("hides the internal resuming state after Continue is accepted", async () => {
+    const onContinue = vi.fn().mockResolvedValue(undefined);
+
+    render(
+      <RecoveryNotice
+        state={INTERRUPTED}
+        onContinue={onContinue}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Continue" }));
+
+    await waitFor(() => expect(screen.queryByRole("alert")).not.toBeInTheDocument());
+    expect(onContinue).toHaveBeenCalledOnce();
+  });
+
+  it("uses the shared status surface and motion treatment", () => {
+    render(
+      <RecoveryNotice
+        state={{ status: "resuming", recovery_id: "recovery-1" }}
+        onContinue={vi.fn().mockResolvedValue(undefined)}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    const notice = screen.getByRole("status");
+    expect(notice).toHaveAttribute("data-recovery-status", "resuming");
+    expect(notice).toHaveAttribute("aria-live", "polite");
+    expect(notice).toHaveClass(
+      "max-w-[49.5rem]",
+      "rounded-control",
+      "animate-in",
+      "fade-in-0",
+      "slide-in-from-bottom-1",
+      "duration-200",
+      "motion-reduce:animate-none",
+    );
+  });
+
+  it("keeps the notice visible when Continue fails", async () => {
+    const onContinue = vi.fn().mockRejectedValue(new Error("offline"));
+
+    render(
+      <RecoveryNotice
+        state={INTERRUPTED}
+        onContinue={onContinue}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Continue" }));
+
+    await waitFor(() => {
+      expect(screen.getByRole("alert")).toHaveTextContent("Recovery action failed");
+    });
+  });
+
+  it("shows the decision surface again when a continuation is interrupted", async () => {
+    const onContinue = vi.fn().mockResolvedValue(undefined);
+    const { rerender } = render(
+      <RecoveryNotice
+        state={INTERRUPTED}
+        onContinue={onContinue}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Continue" }));
+    await waitFor(() => expect(screen.queryByRole("alert")).not.toBeInTheDocument());
+
+    rerender(
+      <RecoveryNotice
+        state={{ status: "resuming", recovery_id: "recovery-1" }}
+        onContinue={onContinue}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+    rerender(
+      <RecoveryNotice
+        state={{ ...INTERRUPTED, reason: "loop_guard" }}
+        onContinue={onContinue}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    await waitFor(() => expect(screen.getByRole("alert")).toBeInTheDocument());
+  });
+
+  it("does not offer Continue when saved conversation context is unavailable", () => {
+    render(
+      <RecoveryNotice
+        state={{ ...INTERRUPTED, can_continue: false }}
+        onContinue={vi.fn().mockResolvedValue(undefined)}
+        onDismiss={vi.fn().mockResolvedValue(undefined)}
+      />,
+    );
+
+    expect(screen.queryByRole("button", { name: "Continue" })).not.toBeInTheDocument();
+    expect(screen.getByRole("button", { name: "Dismiss" })).toBeInTheDocument();
+  });
+});

webui/src/tests/thread-shell.test.tsx

@@ -4007,4 +4007,32 @@ describe("ThreadShell", () => {
     expect(screen.getByRole("option", { name: /Other project/i })).toBeInTheDocument();
   });
 
+  it("allows a new turn after a completed recovery state", async () => {
+    const client = makeClient();
+    render(wrap(
+      client,
+      <ThreadShell
+        session={session("recovered-chat")}
+        title="Recovered chat"
+        onToggleSidebar={() => {}}
+      />,
+    ));
+
+    const input = await screen.findByLabelText("Message input");
+    act(() => {
+      client._emitChat("recovered-chat", {
+        event: "recovery_state",
+        chat_id: "recovered-chat",
+        recovery_id: "recovery-1",
+        status: "recovered",
+      });
+    });
+
+    fireEvent.change(input, { target: { value: "start the next task" } });
+    fireEvent.click(screen.getByRole("button", { name: "Send message" }));
+
+    expect(client.sendMessage).toHaveBeenCalledOnce();
+    expect(screen.getByRole("button", { name: "Stop response" })).toBeInTheDocument();
+  });
+
 });

webui/src/tests/useNanobotStream.test.tsx

@@ -73,6 +73,7 @@ function fakeClient() {
   const runStartedAtByChatId = new Map<string, number>();
   const unsettledRunByChatId = new Map<string, boolean>();
   const goalStateByChatId = new Map<string, GoalStateWsPayload>();
+  const requestMutation = vi.fn().mockResolvedValue({});
   let status: ConnectionStatus = "open";
 
   function recordGoalStatusForRunStrip(chatId: string, ev: InboundEvent) {
@@ -133,6 +134,7 @@ function fakeClient() {
         return () => set!.delete(h);
       },
       sendMessage: vi.fn(),
+      requestMutation,
       finishRunLocally: vi.fn(),
       newChat: vi.fn(),
       forkChat: vi.fn(),
@@ -157,6 +159,7 @@ function fakeClient() {
     setUnsettled(chatId: string, unsettled: boolean) {
       unsettledRunByChatId.set(chatId, unsettled);
     },
+    requestMutation,
   };
 }
 
@@ -395,6 +398,101 @@ describe("useNanobotStream", () => {
     });
   });
 
+  it("exposes typed recovery state and validates actions with its recovery id", async () => {
+    const fake = fakeClient();
+    const { result } = renderHook(() => useNanobotStream("chat-recovery", EMPTY_MESSAGES), {
+      wrapper: wrap(fake.client),
+    });
+
+    act(() => {
+      fake.emit("chat-recovery", {
+        event: "goal_status",
+        chat_id: "chat-recovery",
+        status: "running",
+        started_at: 1_700,
+      });
+    });
+    expect(result.current.runStartedAt).toBe(1_700);
+
+    act(() => {
+      fake.emit("chat-recovery", {
+        event: "recovery_state",
+        chat_id: "chat-recovery",
+        recovery_id: "recovery-1",
+        status: "awaiting_user",
+        reason: "tool_state_uncertain",
+        can_continue: false,
+      });
+    });
+
+    expect(result.current.recoveryState).toEqual({
+      recovery_id: "recovery-1",
+      status: "awaiting_user",
+      reason: "tool_state_uncertain",
+      can_continue: false,
+    });
+    expect(result.current.isStreaming).toBe(false);
+    expect(result.current.runStartedAt).toBeNull();
+    expect(fake.client.finishRunLocally).toHaveBeenCalledWith("chat-recovery");
+
+    act(() => {
+      fake.emit("chat-recovery", {
+        event: "recovery_state",
+        chat_id: "chat-recovery",
+        recovery_id: "recovery-1",
+        status: "awaiting_user",
+        reason: "tool_state_uncertain",
+        can_continue: true,
+      });
+    });
+
+    await act(async () => result.current.continueRecovery());
+    expect(fake.requestMutation).toHaveBeenCalledWith("recovery.continue", {
+      chat_id: "chat-recovery",
+      recovery_id: "recovery-1",
+    });
+
+    act(() => {
+      fake.emit("chat-recovery", {
+        event: "recovery_state",
+        chat_id: "chat-recovery",
+        recovery_id: "recovery-1",
+        status: "recovered",
+      });
+    });
+    expect(result.current.isStreaming).toBe(false);
+    expect(fake.client.finishRunLocally).toHaveBeenCalledWith("chat-recovery");
+  });
+
+  it("does not let historical recovered state clear a later active turn", () => {
+    const fake = fakeClient();
+    const { result } = renderHook(
+      () => useNanobotStream("chat-recovered-history", EMPTY_MESSAGES),
+      { wrapper: wrap(fake.client) },
+    );
+
+    act(() => {
+      fake.emit("chat-recovered-history", {
+        event: "goal_status",
+        chat_id: "chat-recovered-history",
+        status: "running",
+        started_at: 1_700,
+      });
+      fake.emit("chat-recovered-history", {
+        event: "attached",
+        chat_id: "chat-recovered-history",
+        recovery_state: {
+          recovery_id: "old-recovery",
+          status: "recovered",
+        },
+      });
+    });
+
+    expect(result.current.isStreaming).toBe(true);
+    expect(result.current.runStartedAt).toBe(1_700);
+    expect(fake.client.finishRunLocally).not.toHaveBeenCalled();
+  });
+
   it("preserves proactive automation source metadata on complete assistant messages", () => {
     const fake = fakeClient();
     const { result } = renderHook(() => useNanobotStream("chat-cron", EMPTY_MESSAGES), {