feat(providers): add Grok 4.6 subscription model

tests/cli/test_commands.py

@@ -799,7 +799,7 @@ def test_provider_login_can_set_xai_grok_as_main_provider(tmp_path):
 
     saved = Config.model_validate(json.loads(config_path.read_text(encoding="utf-8")))
     assert saved.agents.defaults.provider == "xai_grok"
-    assert saved.agents.defaults.model == "xai-grok/grok-4.5"
+    assert saved.agents.defaults.model == "xai-grok/grok-4.6"
     assert saved.agents.defaults.context_window_tokens == 500_000
     assert saved.agents.defaults.model_preset is None
     assert make_provider(saved).__class__.__name__ == "XAIGrokProvider"

tests/providers/test_xai_grok_provider.py

@@ -52,7 +52,10 @@ def _mock_model_capabilities(
     supports_backend_search: bool,
 ) -> None:
     async def fake_fetch(*_args, **_kwargs):
-        return {"grok-4.5": supports_backend_search}
+        return {
+            "grok-4.5": supports_backend_search,
+            "grok-4.6": supports_backend_search,
+        }
 
     monkeypatch.setattr(
         "nanobot.providers.xai_grok_provider._fetch_xai_model_capabilities",
@@ -60,13 +63,17 @@ def _mock_model_capabilities(
     )
 
 
-def test_xai_grok_registry_exposes_curated_x_search_model() -> None:
+def test_xai_grok_registry_exposes_curated_x_search_models() -> None:
     spec = find_by_name("xai_grok")
 
     assert spec is not None
     assert spec.is_oauth is True
     assert spec.backend == "xai_grok"
     assert spec.builtin_models[0].id == DEFAULT_XAI_GROK_MODEL
+    assert [model.id for model in spec.builtin_models] == [
+        "xai-grok/grok-4.6",
+        "xai-grok/grok-4.5",
+    ]
     assert spec.builtin_models[0].context_window == 500000
     assert "when supported" in spec.builtin_models[0].description
 
@@ -117,7 +124,7 @@ async def test_provider_injects_hosted_x_search_and_required_proxy_headers(monke
     assert response.content == "answer [[1]](https://x.com/example/status/1)"
     url, headers, body = calls[0]
     assert url == "https://cli-chat-proxy.grok.com/v1/responses"
-    assert body["model"] == "grok-4.5"
+    assert body["model"] == "grok-4.6"
     assert body["tools"] == [
         {
             "type": "function",
@@ -137,7 +144,7 @@ async def test_provider_injects_hosted_x_search_and_required_proxy_headers(monke
     assert headers["x-authenticateresponse"] == "authenticate-response"
     assert headers["x-grok-client-identifier"] == "nanobot"
     assert headers["x-grok-client-mode"] == "headless"
-    assert headers["x-grok-model-override"] == "grok-4.5"
+    assert headers["x-grok-model-override"] == "grok-4.6"
 
 
 @pytest.mark.asyncio

tests/webui/test_settings_api.py

@@ -2015,12 +2015,19 @@ def test_provider_models_payload_returns_curated_openai_codex_models() -> None:
     ]
 
 
-def test_provider_models_payload_returns_xai_grok_model() -> None:
+def test_provider_models_payload_returns_xai_grok_models() -> None:
     payload = provider_models_payload({"provider": ["xai_grok"]})
 
     assert payload["status"] == "available"
     assert payload["catalog_kind"] == "builtin"
     assert payload["models"] == [
+        {
+            "id": "xai-grok/grok-4.6",
+            "label": "Grok 4.6",
+            "description": "Grok via xAI subscription; X Search is enabled when supported.",
+            "owned_by": "xAI Grok",
+            "context_window": 500000,
+        },
         {
             "id": "xai-grok/grok-4.5",
             "label": "Grok 4.5",