feat(devgen/providers):improve provider error handling and response parsing

devgen/providers/__init__.py

@@ -1,24 +0,0 @@
-def get_provider(name):
-    name_lower = name.lower()
-    if name_lower == "gemini":
-        from devgen.providers.gemini import GeminiProvider
-
-        return GeminiProvider()
-    elif name_lower == "openai":
-        from devgen.providers.openai import OpenaiProvider
-
-        return OpenaiProvider()
-    elif name_lower == "huggingface":
-        from devgen.providers.huggingface import HuggingfaceProvider
-
-        return HuggingfaceProvider()
-    elif name_lower == "openrouter":
-        from devgen.providers.openrouter import OpenrouterProvider
-
-        return OpenrouterProvider()
-    elif name_lower == "anthropic":
-        from devgen.providers.anthropic import AnthropicProvider
-
-        return AnthropicProvider()
-
-    raise NotImplementedError(f"Provider '{name}' is not implemented yet.")

devgen/providers/anthropic.py

@@ -9,7 +9,10 @@ class AnthropicProvider:
     ) -> str:
         """Generates a response using the Anthropic API."""
         if not api_key:
-            raise ValueError("Anthropic API key is required.")
+            raise ValueError(
+                "Anthropic API key is missing. "
+                "Set it via `devgen setup config` or pass --api-key."
+            )
 
         try:
             client = anthropic.Anthropic(api_key=api_key)

devgen/providers/gemini.py

@@ -15,7 +15,10 @@ class GeminiProvider:
         recommended model.
         """
         if not api_key:
-            raise ValueError("Gemini API key is required.")
+            raise ValueError(
+                "Gemini API key is missing. "
+                "Set it via `devgen setup config` or pass --api-key."
+            )
 
         client = genai.Client(api_key=api_key)
 

devgen/providers/huggingface.py

@@ -15,7 +15,10 @@ class HuggingfaceProvider:
     ) -> str:
         """Generates a response using Hugging Face API."""
         if not api_key:
-            raise ValueError("Hugging Face API token is required.")
+            raise ValueError(
+                "Hugging Face API token is missing. "
+                "Set it via `devgen setup config` or pass --api-key."
+            )
 
         api_url = self.API_URL_TEMPLATE.format(model=model)
         headers = {"Authorization": f"Bearer {api_key}"}
@@ -34,12 +37,31 @@ class HuggingfaceProvider:
             response.raise_for_status()
             result = response.json()
 
-            if isinstance(result, list) and "generated_text" in result[0]:
+            if isinstance(result, list) and result and "generated_text" in result[0]:
                 return result[0]["generated_text"].strip()
             elif isinstance(result, dict) and "error" in result:
-                raise RuntimeError(f"Hugging Face API error: {result['error']}")
+                err = result["error"]
+                if "is currently loading" in str(err).lower():
+                    raise RuntimeError(
+                        f"Hugging Face model is loading: {err}. "
+                        "Wait a minute and retry, or pick a different model."
+                    )
+                raise RuntimeError(f"Hugging Face API error: {err}")
             else:
-                return str(result)
+                raise RuntimeError(
+                    "Hugging Face returned an unexpected response shape. "
+                    "The model may not support text-generation."
+                )
 
+        except requests.HTTPError as e:
+            status = e.response.status_code if e.response is not None else "?"
+            raise RuntimeError(
+                f"Hugging Face request failed (HTTP {status}): {e}. "
+                "Check the model id and your token permissions."
+            ) from e
+        except requests.RequestException as e:
+            raise RuntimeError(
+                f"Hugging Face network error: {e}. Check your connection."
+            ) from e
         except Exception as e:
-            raise RuntimeError(f"Hugging Face generation failed: {e}")
+            raise RuntimeError(f"Hugging Face generation failed: {e}") from e

devgen/providers/openai.py

@@ -32,20 +32,35 @@ class OpenaiProvider:
         Returns:
             str: Generated response content.
         """
+        if not api_key:
+            raise ValueError(
+                "OpenAI API key is missing. "
+                "Set it via `devgen setup config` or pass --api-key."
+            )
+
         # 1. Create a client instance with the API key.
         try:
             client = OpenAI(api_key=api_key)
         except Exception as e:
             # Add error handling if the client fails to initialize
-            raise RuntimeError(f"Failed to initialize OpenAI client: {e}")
+            raise RuntimeError(
+                f"Failed to initialize OpenAI client: {e}. "
+                "Verify the key is valid and that the `openai` package is installed."
+            ) from e
 
         # Remove debug from kwargs if present
         kwargs.pop("debug", None)
 
         # 2. Use the modern API syntax: client.chat.completions.create
-        response = client.chat.completions.create(
-            model=model or self.DEFAULT_MODEL,
-            messages=[{"role": "user", "content": prompt}],
-            **kwargs,
-        )
+        try:
+            response = client.chat.completions.create(
+                model=model or self.DEFAULT_MODEL,
+                messages=[{"role": "user", "content": prompt}],
+                **kwargs,
+            )
+        except Exception as e:
+            raise RuntimeError(
+                f"OpenAI request failed: {e}. "
+                "Check the model name, API key permissions, and your account quota."
+            ) from e
         return response.choices[0].message.content.strip()

devgen/providers/openrouter.py

@@ -11,7 +11,10 @@ class OpenrouterProvider:
     ) -> str:
         """Generates a response using OpenRouter."""
         if not api_key:
-            raise ValueError("OpenRouter API key is required.")
+            raise ValueError(
+                "OpenRouter API key is missing. "
+                "Set it via `devgen setup config` or pass --api-key."
+            )
 
         try:
             client = OpenAI(
@@ -33,4 +36,7 @@ class OpenrouterProvider:
             )
             return response.choices[0].message.content.strip()
         except Exception as e:
-            raise RuntimeError(f"OpenRouter generation failed: {e}")
+            raise RuntimeError(
+                f"OpenRouter request failed: {e}. "
+                "Verify the model id (e.g. `openai/gpt-4o`) and your API key credits."
+            ) from e