Update app.py

app.py

@@ -150,7 +150,25 @@ class OptionalHFInferenceClient:
         from huggingface_hub import InferenceClient
 
         self.model_id = model_id.strip().strip('"').strip("'").strip()
-        self.client = InferenceClient(model=self.model_id, token=token)
+
+        api_key = (
+            token
+            or os.getenv("HF_TOKEN")
+            or os.getenv("HF_HUB_TOKEN")
+            or os.getenv("HUGGINGFACEHUB_API_TOKEN")
+        )
+
+        if not api_key:
+            raise RuntimeError(
+                "HF_TOKEN is required for Hugging Face Inference Providers. "
+                "Create a Hugging Face token with Inference Providers permission "
+                "and add it as a Space secret named HF_TOKEN."
+            )
+
+        self.client = InferenceClient(
+            model=self.model_id,
+            api_key=api_key,
+        )
 
     def generate(
         self,
@@ -351,8 +369,12 @@ def build_optional_model_client() -> tuple[Any | None, AppModelStatus]:
         os.getenv("WORLDSMITHAI_MODEL_ID")
         or os.getenv("WORLD_SMITH_MODEL_ID")
         or os.getenv("HF_MODEL_ID")
-    )
-    token = os.getenv("HF_TOKEN") or os.getenv("HUGGINGFACEHUB_API_TOKEN")
+            )
+    token = (
+            os.getenv("HF_TOKEN")
+            or os.getenv("HF_HUB_TOKEN")
+            or os.getenv("HUGGINGFACEHUB_API_TOKEN")
+            )
 
     if not raw_model_id:
         return None, AppModelStatus(