fix(models): scope prefix routing to user-configured providers only

hermes_cli/models.py

@@ -3640,14 +3640,21 @@ def _configured_provider_ids() -> set[str]:
 
 
 def _resolve_provider_prefix(model_name: str) -> Optional[tuple[str, str]]:
-    """Resolve an explicit ``vendor/model`` prefix to a known provider.
+    """Resolve an explicit ``vendor/model`` prefix to a configured provider.
 
     ``nous/deepseek-v4-pro`` or ``ollama/qwen3.5:4b`` should route to the
     named provider instead of falling back to the configured default (which
-    silently sends non-default models to the wrong endpoint, #87189). The
-    vendor counts as known when it is a built-in provider id/alias or a key
-    in the user's ``providers:`` config block. The returned model is the
-    suffix with the prefix stripped — the provider's API expects the bare id.
+    silently sends non-default models to the wrong endpoint, #87189).
+
+    Only vendors the user actually defined in their ``providers:`` config
+    block (by raw name or alias) are routed here. Built-in vendor prefixes
+    (``google/gemini-2.5-flash``, ``deepseek/deepseek-chat``) deliberately
+    stay on the existing catalog / OpenRouter-slug / default-provider path:
+    those slug forms are aggregator-native, and rerouting them to the vendor
+    provider would change established provider-switch behavior (see
+    ``TestDenormalizeProviderSwitch`` in tests/hermes_cli/test_web_server.py).
+    The returned model is the suffix with the prefix stripped — the target
+    provider's API expects the bare id.
     """
     if "/" not in model_name:
         return None
@@ -3657,20 +3664,17 @@ def _resolve_provider_prefix(model_name: str) -> Optional[tuple[str, str]]:
     if not vendor or not model:
         return None
     configured = _configured_provider_ids()
+    if not configured:
+        return None
     # A provider block the user explicitly named (``ollama:``) wins over the
     # built-in alias table, which may canonicalize the same name elsewhere
     # (``ollama`` → ``custom``) and route to the wrong endpoint.
     if vendor in configured:
         return (vendor, model)
     canonical = _PROVIDER_ALIASES.get(vendor, vendor)
-    known = (
-        canonical in _PROVIDER_LABELS
-        or canonical in _PROVIDER_MODELS
-        or canonical in configured
-    )
-    if not known:
-        return None
-    return (canonical, model)
+    if canonical in configured:
+        return (canonical, model)
+    return None
 
 
 def detect_provider_for_model(
@@ -3709,11 +3713,12 @@ def detect_provider_for_model(
             return ("openrouter", or_slug)
         return None  # already on openrouter with matching name
 
-    # --- Step 3: explicit ``vendor/model`` prefix naming a provider ---
+    # --- Step 3: explicit ``vendor/model`` prefix naming a configured provider ---
     # Checked after the OpenRouter slug lookup so aggregator-native slugs
-    # (e.g. ``deepseek/deepseek-chat``) keep their existing routing; this
-    # step only catches names no catalog serves, which previously fell back
-    # to the configured default provider and 404'd (#87189).
+    # (e.g. ``deepseek/deepseek-chat``) keep their existing routing; only
+    # vendors the user defined in their ``providers:`` block route here,
+    # so catalog/default behavior for built-in vendor prefixes is unchanged
+    # (#87189).
     prefix_match = _resolve_provider_prefix(name)
     if prefix_match is not None:
         return prefix_match

tests/hermes_cli/test_model_prefix_routing_87189.py

@@ -12,19 +12,37 @@ import hermes_cli.model_switch as model_switch
 
 
 class TestVendorPrefixRouting:
-    """detect_provider_for_model honors an explicit ``vendor/model`` prefix."""
+    """detect_provider_for_model honors a ``vendor/model`` prefix for
+    providers the user actually configured in their ``providers:`` block."""
 
-    def test_builtin_provider_prefix_routes_to_provider(self, monkeypatch):
+    def test_configured_provider_prefix_routes_to_provider(self, monkeypatch):
         monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
+        monkeypatch.setattr(models, "_configured_provider_ids", lambda: {"nous"})
         detected = models.detect_provider_for_model("nous/deepseek-v4-pro", "anthropic")
         assert detected == ("nous", "deepseek-v4-pro")
 
-    def test_configured_provider_prefix_routes_to_provider(self, monkeypatch):
+    def test_local_provider_prefix_routes_to_provider(self, monkeypatch):
         monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
         monkeypatch.setattr(models, "_configured_provider_ids", lambda: {"ollama"})
         detected = models.detect_provider_for_model("ollama/qwen3.5:4b", "anthropic")
         assert detected == ("ollama", "qwen3.5:4b")
 
+    def test_unconfigured_builtin_vendor_prefix_not_rerouted(self, monkeypatch):
+        """Built-in vendor slugs keep catalog/default routing.
+
+        ``google/gemini-2.5-flash`` is aggregator-native: the web config
+        field expects it to switch to OpenRouter, not to the Gemini provider
+        (``TestDenormalizeProviderSwitch`` in test_web_server.py). With no
+        user-configured provider for the vendor, prefix routing must stay
+        out of the way even when the models.dev catalog is unavailable.
+        """
+        monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
+        monkeypatch.setattr(models, "_configured_provider_ids", lambda: set())
+        detected = models.detect_provider_for_model(
+            "google/gemini-2.5-flash", "ollama-local"
+        )
+        assert detected is None
+
     def test_configured_provider_wins_over_alias_canonicalization(self, monkeypatch):
         """A user-named ``ollama`` block must not be rewritten to ``custom``."""
         monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
@@ -33,15 +51,15 @@ class TestVendorPrefixRouting:
         detected = models.detect_provider_for_model("ollama/qwen3.5:4b", "anthropic")
         assert detected == ("ollama", "qwen3.5:4b")
 
-    def test_provider_alias_prefix_canonicalized(self, monkeypatch):
+    def test_provider_alias_prefix_canonicalized_when_configured(self, monkeypatch):
         monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
-        monkeypatch.setattr(models, "_configured_provider_ids", lambda: set())
+        monkeypatch.setattr(models, "_configured_provider_ids", lambda: {"zai"})
         detected = models.detect_provider_for_model("glm/glm-4.7", "anthropic")
         assert detected == ("zai", "glm-4.7")
 
     def test_unknown_vendor_prefix_still_unmatched(self, monkeypatch):
         monkeypatch.setattr(models, "_find_openrouter_slug", lambda _name: None)
-        monkeypatch.setattr(models, "_configured_provider_ids", lambda: set())
+        monkeypatch.setattr(models, "_configured_provider_ids", lambda: {"ollama"})
         assert models.detect_provider_for_model("notaprovider/foo-model", "anthropic") is None
 
     def test_openrouter_slug_still_wins_over_prefix_routing(self, monkeypatch):
@@ -49,7 +67,7 @@ class TestVendorPrefixRouting:
         monkeypatch.setattr(
             models, "_find_openrouter_slug", lambda _name: "deepseek/deepseek-chat"
         )
-        monkeypatch.setattr(models, "_configured_provider_ids", lambda: set())
+        monkeypatch.setattr(models, "_configured_provider_ids", lambda: {"deepseek"})
         detected = models.detect_provider_for_model("deepseek/deepseek-chat", "anthropic")
         assert detected == ("openrouter", "deepseek/deepseek-chat")