Update app.py

app.py

@@ -23,13 +23,13 @@ OPENROUTER_BASE_URL = "https://openrouter.ai/api/v1"
 TEXT_MODELS = [
     m.strip() for m in os.getenv(
         "OPENROUTER_MODELS",
-        # Best free models for tool use as of 2025-2026.
-        "deepseek/deepseek-chat-v3-0324:free,"
+        # Currently-valid free OpenRouter models (verify at https://openrouter.ai/models?q=free).
         "meta-llama/llama-3.3-70b-instruct:free,"
         "mistralai/mistral-small-3.2-24b-instruct:free,"
         "google/gemini-2.0-flash-exp:free,"
         "qwen/qwen-2.5-72b-instruct:free,"
-        "deepseek/deepseek-r1:free"
+        "deepseek/deepseek-r1:free,"
+        "deepseek/deepseek-chat:free"
     ).split(",")
     if m.strip()
 ]
@@ -612,6 +612,17 @@ class OpenRouterAgent:
                     is_rate = "429" in msg or "rate" in msg.lower() or "limit" in msg.lower()
                     is_quota = ("daily" in msg.lower() or "quota" in msg.lower()
                                 or "exhausted" in msg.lower())
+                    # 404 / "No endpoints found" / "model not found" -> dead model, never retry.
+                    is_dead = (
+                        "404" in msg
+                        or "no endpoints" in msg.lower()
+                        or "not found" in msg.lower()
+                        or "model_not_found" in msg.lower()
+                    )
+                    if is_dead:
+                        print(f"[{m}] model unavailable (404 / no endpoints); marking exhausted.")
+                        self.exhausted.add(m)
+                        break
                     if is_rate and is_quota:
                         print(f"[{m}] daily quota exhausted; switching model.")
                         self.exhausted.add(m)