fix: forward auth when probing local model metadata

Pass the user's configured api_key through local-server detection and
context-length probes (detect_local_server_type, _query_local_context_length,
query_ollama_num_ctx) and use LM Studio's native /api/v1/models endpoint in
fetch_endpoint_model_metadata when a loaded instance is present — so the
probed context length is the actual runtime value the user loaded the model
at, not just the model's theoretical max.

Helps local-LLM users whose auto-detected context length was wrong, causing
compression failures and context-overrun crashes.

agent/model_metadata.py

@@ -210,6 +210,13 @@ def _normalize_base_url(base_url: str) -> str:
     return (base_url or "").strip().rstrip("/")
 
 
+def _auth_headers(api_key: str = "") -> Dict[str, str]:
+    token = str(api_key or "").strip()
+    if not token:
+        return {}
+    return {"Authorization": f"Bearer {token}"}
+
+
 def _is_openrouter_base_url(base_url: str) -> bool:
     return "openrouter.ai" in _normalize_base_url(base_url).lower()
 
@@ -309,7 +316,7 @@ def is_local_endpoint(base_url: str) -> bool:
     return False
 
 
-def detect_local_server_type(base_url: str) -> Optional[str]:
+def detect_local_server_type(base_url: str, api_key: str = "") -> Optional[str]:
     """Detect which local server is running at base_url by probing known endpoints.
 
     Returns one of: "ollama", "lm-studio", "vllm", "llamacpp", or None.
@@ -321,8 +328,10 @@ def detect_local_server_type(base_url: str) -> Optional[str]:
     if server_url.endswith("/v1"):
         server_url = server_url[:-3]
 
+    headers = _auth_headers(api_key)
+
     try:
-        with httpx.Client(timeout=2.0) as client:
+        with httpx.Client(timeout=2.0, headers=headers) as client:
             # LM Studio exposes /api/v1/models — check first (most specific)
             try:
                 r = client.get(f"{server_url}/api/v1/models")
@@ -509,6 +518,59 @@ def fetch_endpoint_model_metadata(
     headers = {"Authorization": f"Bearer {api_key}"} if api_key else {}
     last_error: Optional[Exception] = None
 
+    if is_local_endpoint(normalized):
+        try:
+            if detect_local_server_type(normalized, api_key=api_key) == "lm-studio":
+                server_url = normalized[:-3].rstrip("/") if normalized.endswith("/v1") else normalized
+                response = requests.get(
+                    server_url.rstrip("/") + "/api/v1/models",
+                    headers=headers,
+                    timeout=10,
+                )
+                response.raise_for_status()
+                payload = response.json()
+                cache: Dict[str, Dict[str, Any]] = {}
+                for model in payload.get("models", []):
+                    if not isinstance(model, dict):
+                        continue
+                    model_id = model.get("key") or model.get("id")
+                    if not model_id:
+                        continue
+                    entry: Dict[str, Any] = {"name": model.get("name", model_id)}
+
+                    context_length = None
+                    for inst in model.get("loaded_instances", []) or []:
+                        if not isinstance(inst, dict):
+                            continue
+                        cfg = inst.get("config", {})
+                        ctx = cfg.get("context_length") if isinstance(cfg, dict) else None
+                        if isinstance(ctx, int) and ctx > 0:
+                            context_length = ctx
+                            break
+                    if context_length is None:
+                        context_length = _extract_context_length(model)
+                    if context_length is not None:
+                        entry["context_length"] = context_length
+
+                    max_completion_tokens = _extract_max_completion_tokens(model)
+                    if max_completion_tokens is not None:
+                        entry["max_completion_tokens"] = max_completion_tokens
+
+                    pricing = _extract_pricing(model)
+                    if pricing:
+                        entry["pricing"] = pricing
+
+                    _add_model_aliases(cache, model_id, entry)
+                    alt_id = model.get("id")
+                    if isinstance(alt_id, str) and alt_id and alt_id != model_id:
+                        _add_model_aliases(cache, alt_id, entry)
+
+                _endpoint_model_metadata_cache[normalized] = cache
+                _endpoint_model_metadata_cache_time[normalized] = time.time()
+                return cache
+        except Exception as exc:
+            last_error = exc
+
     for candidate in candidates:
         url = candidate.rstrip("/") + "/models"
         try:
@@ -715,7 +777,7 @@ def _model_id_matches(candidate_id: str, lookup_model: str) -> bool:
     return False
 
 
-def query_ollama_num_ctx(model: str, base_url: str) -> Optional[int]:
+def query_ollama_num_ctx(model: str, base_url: str, api_key: str = "") -> Optional[int]:
     """Query an Ollama server for the model's context length.
 
     Returns the model's maximum context from GGUF metadata via ``/api/show``,
@@ -733,14 +795,16 @@ def query_ollama_num_ctx(model: str, base_url: str) -> Optional[int]:
         server_url = server_url[:-3]
 
     try:
-        server_type = detect_local_server_type(base_url)
+        server_type = detect_local_server_type(base_url, api_key=api_key)
     except Exception:
         return None
     if server_type != "ollama":
         return None
 
+    headers = _auth_headers(api_key)
+
     try:
-        with httpx.Client(timeout=3.0) as client:
+        with httpx.Client(timeout=3.0, headers=headers) as client:
             resp = client.post(f"{server_url}/api/show", json={"name": bare_model})
             if resp.status_code != 200:
                 return None
@@ -768,7 +832,7 @@ def query_ollama_num_ctx(model: str, base_url: str) -> Optional[int]:
     return None
 
 
-def _query_local_context_length(model: str, base_url: str) -> Optional[int]:
+def _query_local_context_length(model: str, base_url: str, api_key: str = "") -> Optional[int]:
     """Query a local server for the model's context length."""
     import httpx
 
@@ -781,13 +845,15 @@ def _query_local_context_length(model: str, base_url: str) -> Optional[int]:
     if server_url.endswith("/v1"):
         server_url = server_url[:-3]
 
+    headers = _auth_headers(api_key)
+
     try:
-        server_type = detect_local_server_type(base_url)
+        server_type = detect_local_server_type(base_url, api_key=api_key)
     except Exception:
         server_type = None
 
     try:
-        with httpx.Client(timeout=3.0) as client:
+        with httpx.Client(timeout=3.0, headers=headers) as client:
             # Ollama: /api/show returns model details with context info
             if server_type == "ollama":
                 resp = client.post(f"{server_url}/api/show", json={"name": model})
@@ -998,7 +1064,7 @@ def get_model_context_length(
         if not _is_known_provider_base_url(base_url):
             # 3. Try querying local server directly
             if is_local_endpoint(base_url):
-                local_ctx = _query_local_context_length(model, base_url)
+                local_ctx = _query_local_context_length(model, base_url, api_key=api_key)
                 if local_ctx and local_ctx > 0:
                     save_context_length(model, base_url, local_ctx)
                     return local_ctx
@@ -1068,7 +1134,7 @@ def get_model_context_length(
 
     # 9. Query local server as last resort
     if base_url and is_local_endpoint(base_url):
-        local_ctx = _query_local_context_length(model, base_url)
+        local_ctx = _query_local_context_length(model, base_url, api_key=api_key)
         if local_ctx and local_ctx > 0:
             save_context_length(model, base_url, local_ctx)
             return local_ctx

gateway/run.py

@@ -3876,9 +3876,11 @@ class GatewayRunner:
                 from agent.model_metadata import get_model_context_length
 
                 _msg_cwd = os.environ.get("TERMINAL_CWD", os.path.expanduser("~"))
+                _msg_runtime = _resolve_runtime_agent_kwargs()
                 _msg_ctx_len = get_model_context_length(
                     self._model,
-                    base_url=self._base_url or "",
+                    base_url=self._base_url or _msg_runtime.get("base_url") or "",
+                    api_key=_msg_runtime.get("api_key") or "",
                 )
                 _ctx_result = await preprocess_context_references_async(
                     message_text,

tests/agent/test_model_metadata_local_ctx.py

@@ -424,6 +424,68 @@ class TestQueryLocalContextLengthLmStudio:
         )
 
 
+class TestDetectLocalServerTypeAuth:
+    def test_passes_bearer_token_to_probe_requests(self):
+        from agent.model_metadata import detect_local_server_type
+
+        resp = MagicMock()
+        resp.status_code = 200
+
+        client_mock = MagicMock()
+        client_mock.__enter__ = lambda s: client_mock
+        client_mock.__exit__ = MagicMock(return_value=False)
+        client_mock.get.return_value = resp
+
+        with patch("httpx.Client", return_value=client_mock) as mock_client:
+            result = detect_local_server_type("http://localhost:1234/v1", api_key="lm-token")
+
+        assert result == "lm-studio"
+        assert mock_client.call_args.kwargs["headers"] == {
+            "Authorization": "Bearer lm-token"
+        }
+
+
+class TestFetchEndpointModelMetadataLmStudio:
+    """fetch_endpoint_model_metadata should use LM Studio's native models endpoint."""
+
+    def _make_resp(self, body):
+        resp = MagicMock()
+        resp.raise_for_status.return_value = None
+        resp.json.return_value = body
+        return resp
+
+    def test_uses_native_models_endpoint_only(self):
+        from agent.model_metadata import fetch_endpoint_model_metadata
+
+        native_resp = self._make_resp(
+            {
+                "models": [
+                    {
+                        "key": "lmstudio-community/Qwen3.5-27B-GGUF/Qwen3.5-27B-Q8_0.gguf",
+                        "id": "lmstudio-community/Qwen3.5-27B-GGUF/Qwen3.5-27B-Q8_0.gguf",
+                        "max_context_length": 131072,
+                    }
+                ]
+            }
+        )
+
+        with patch("agent.model_metadata.detect_local_server_type", return_value="lm-studio"), \
+             patch("agent.model_metadata.requests.get", return_value=native_resp) as mock_get:
+            result = fetch_endpoint_model_metadata(
+                "http://localhost:1234/v1",
+                api_key="lm-token",
+                force_refresh=True,
+            )
+
+        assert mock_get.call_count == 1
+        assert mock_get.call_args[0][0] == "http://localhost:1234/api/v1/models"
+        assert mock_get.call_args.kwargs["headers"] == {
+            "Authorization": "Bearer lm-token"
+        }
+        assert result["lmstudio-community/Qwen3.5-27B-GGUF/Qwen3.5-27B-Q8_0.gguf"]["context_length"] == 131072
+        assert result["Qwen3.5-27B-GGUF/Qwen3.5-27B-Q8_0.gguf"]["context_length"] == 131072
+
+
 class TestQueryLocalContextLengthNetworkError:
     """_query_local_context_length handles network failures gracefully."""