diff --git a/nanobot/agent/runner.py b/nanobot/agent/runner.py
index 373d21815..bba644bd0 100644
--- a/nanobot/agent/runner.py
+++ b/nanobot/agent/runner.py
@@ -612,7 +612,7 @@ class AgentRunner:
         wants_progress_streaming = (
             not wants_streaming
             and spec.progress_callback is not None
-            and getattr(self.provider, "stream_progress_via_chat_stream", False) is True
+            and getattr(self.provider, "supports_progress_deltas", False) is True
         )
 
         if wants_streaming:
diff --git a/nanobot/providers/base.py b/nanobot/providers/base.py
index 40072b82e..a60ea09eb 100644
--- a/nanobot/providers/base.py
+++ b/nanobot/providers/base.py
@@ -91,7 +91,7 @@ _SYNTHETIC_USER_CONTENT = "(conversation continued)"
 class LLMProvider(ABC):
     """Base class for LLM providers."""
 
-    stream_progress_via_chat_stream = False
+    supports_progress_deltas = False
 
     _CHAT_RETRY_DELAYS = (1, 2, 4)
     _PERSISTENT_MAX_DELAY = 60
diff --git a/nanobot/providers/openai_codex_provider.py b/nanobot/providers/openai_codex_provider.py
index 103da9a7b..0cc8e5ca2 100644
--- a/nanobot/providers/openai_codex_provider.py
+++ b/nanobot/providers/openai_codex_provider.py
@@ -26,7 +26,7 @@ DEFAULT_ORIGINATOR = "nanobot"
 class OpenAICodexProvider(LLMProvider):
     """Use Codex OAuth to call the Responses API."""
 
-    stream_progress_via_chat_stream = True
+    supports_progress_deltas = True
 
     def __init__(self, default_model: str = "openai-codex/gpt-5.1-codex"):
         super().__init__(api_key=None, api_base=None)
diff --git a/tests/agent/test_loop_progress.py b/tests/agent/test_loop_progress.py
index d4662edad..0c32a8f16 100644
--- a/tests/agent/test_loop_progress.py
+++ b/tests/agent/test_loop_progress.py
@@ -137,7 +137,7 @@ class TestToolEventProgress:
         """Providers that opt in can stream content deltas through _progress messages."""
         bus = MessageBus()
         provider = MagicMock()
-        provider.stream_progress_via_chat_stream = True
+        provider.supports_progress_deltas = True
         provider.get_default_model.return_value = "openai-codex/gpt-5.5"
 
         async def chat_stream_with_retry(*, on_content_delta, **kwargs):
@@ -175,7 +175,7 @@ class TestToolEventProgress:
     ) -> None:
         """If content was already streamed as progress, tool setup should not repeat it."""
         loop = _make_loop(tmp_path)
-        loop.provider.stream_progress_via_chat_stream = True
+        loop.provider.supports_progress_deltas = True
         tool_call = ToolCallRequest(id="call1", name="custom_tool", arguments={"path": "foo.txt"})
         calls = iter([
             LLMResponse(content="I will inspect it.", tool_calls=[tool_call]),
diff --git a/tests/providers/test_providers_init.py b/tests/providers/test_providers_init.py
index 97c869def..620cf8daf 100644
--- a/tests/providers/test_providers_init.py
+++ b/tests/providers/test_providers_init.py
@@ -43,7 +43,7 @@ def test_explicit_provider_import_still_works(monkeypatch) -> None:
     assert "nanobot.providers.anthropic_provider" in sys.modules
 
 
-def test_openai_codex_opts_into_progress_streaming() -> None:
+def test_openai_codex_supports_progress_deltas() -> None:
     from nanobot.providers.openai_codex_provider import OpenAICodexProvider
 
-    assert OpenAICodexProvider.stream_progress_via_chat_stream is True
+    assert OpenAICodexProvider.supports_progress_deltas is True