Update app/providers.py

app/providers.py

@@ -147,7 +147,6 @@ class GeminiProvider(BaseProvider):
             try:
                 r.raise_for_status()
             except httpx.HTTPStatusError as e:
-                # safe_url has no key — params are NOT part of safe_url string
                 raise RuntimeError(
                     f"HTTP {e.response.status_code} from {safe_url}"
                 ) from None
@@ -155,7 +154,11 @@ class GeminiProvider(BaseProvider):
 
 
 class OpenRouterProvider(BaseProvider):
-    """OpenRouter API — OpenAI-compatible chat completions endpoint."""
+    """OpenRouter API — OpenAI-compatible chat completions endpoint.
+    
+    Required headers: HTTP-Referer + X-Title (required by OpenRouter for
+    free models and rate limit attribution).
+    """
 
     async def complete(self, prompt: str, model: str = None, max_tokens: int = 1024) -> str:
         data = await self._post(
@@ -163,6 +166,7 @@ class OpenRouterProvider(BaseProvider):
             headers={
                 "Authorization": f"Bearer {self.key}",
                 "HTTP-Referer":  os.getenv("APP_URL", "https://huggingface.co"),
+                "X-Title":       os.getenv("HUB_NAME", "Universal MCP Hub"),  # required!
                 "content-type":  "application/json",
             },
             payload={
@@ -175,7 +179,11 @@ class OpenRouterProvider(BaseProvider):
 
 
 class HuggingFaceProvider(BaseProvider):
-    """HuggingFace Inference API — chat completions endpoint."""
+    """HuggingFace Inference API — chat completions endpoint.
+    
+    Uses /v1/chat/completions (OpenAI-compatible, requires recent models).
+    Legacy models (410 Gone) must be removed from .pyfun models list.
+    """
 
     async def complete(self, prompt: str, model: str = None, max_tokens: int = 512) -> str:
         m    = model or self.model