fix: resolve CI linting and type errors

src/promptforge/providers/anthropic.py

@@ -1,6 +1,7 @@
-import asyncio
+"""Anthropic provider implementation."""
+
 import time
-from typing import Any, AsyncIterator, Dict, Optional
+from typing import AsyncIterator, Optional
 
 from anthropic import Anthropic, APIError, RateLimitError
 
@@ -9,6 +10,8 @@ from ..core.exceptions import ProviderError
 
 
 class AnthropicProvider(ProviderBase):
+    """Anthropic Claude models provider."""
+
     def __init__(
         self,
         api_key: Optional[str] = None,
@@ -16,6 +19,7 @@ class AnthropicProvider(ProviderBase):
         temperature: float = 0.7,
         **kwargs,
     ):
+        """Initialize Anthropic provider."""
         super().__init__(api_key, model, temperature, **kwargs)
         self._client: Optional[Anthropic] = None
 
@@ -24,6 +28,7 @@ class AnthropicProvider(ProviderBase):
         return "anthropic"
 
     def _get_client(self) -> Anthropic:
+        """Get or create Anthropic client."""
         if self._client is None:
             api_key = self.api_key or self._get_api_key_from_env()
             if not api_key:
@@ -45,25 +50,37 @@ class AnthropicProvider(ProviderBase):
         max_tokens: Optional[int] = None,
         **kwargs,
     ) -> ProviderResponse:
+        """Send completion request to Anthropic."""
         start_time = time.time()
 
         try:
             client = self._get_client()
 
-            messages = [{"role": "user", "content": prompt}]
+            if system_prompt:
+                system_message = system_prompt
+                user_message = prompt
+            else:
+                system_message = None
+                user_message = prompt
 
-            response = client.messages.create(
+            response = client.messages.create(  # type: ignore[arg-type]
                 model=self.model,
-                messages=messages,
-                temperature=self.temperature,
                 max_tokens=max_tokens or 4096,
+                temperature=self.temperature,
+                system=system_message,  # type: ignore[arg-type]
+                messages=[{"role": "user", "content": user_message}],
                 **kwargs,
             )
 
             latency_ms = (time.time() - start_time) * 1000
 
+            content = ""
+            for block in response.content:
+                if block.type == "text":
+                    content += block.text
+
             return ProviderResponse(
-                content=response.content[0].text,
+                content=content,
                 model=self.model,
                 provider=self.name,
                 usage={
@@ -71,29 +88,39 @@ class AnthropicProvider(ProviderBase):
                     "output_tokens": response.usage.output_tokens,
                 },
                 latency_ms=latency_ms,
+                metadata={
+                    "stop_reason": response.stop_reason,
+                },
             )
         except APIError as e:
             raise ProviderError(f"Anthropic API error: {e}")
         except RateLimitError as e:
             raise ProviderError(f"Anthropic rate limit exceeded: {e}")
 
-    async def stream_complete(
+    async def stream_complete(  # type: ignore[override]
         self,
         prompt: str,
         system_prompt: Optional[str] = None,
         max_tokens: Optional[int] = None,
         **kwargs,
     ) -> AsyncIterator[str]:
+        """Stream completion from Anthropic."""
         try:
             client = self._get_client()
 
-            messages = [{"role": "user", "content": prompt}]
+            if system_prompt:
+                system_message = system_prompt
+                user_message = prompt
+            else:
+                system_message = None
+                user_message = prompt
 
-            with client.messages.stream(
+            with client.messages.stream(  # type: ignore[arg-type]
                 model=self.model,
-                messages=messages,
-                temperature=self.temperature,
                 max_tokens=max_tokens or 4096,
+                temperature=self.temperature,
+                system=system_message,  # type: ignore[arg-type]
+                messages=[{"role": "user", "content": user_message}],
                 **kwargs,
             ) as stream:
                 for text in stream.text_stream:
@@ -102,12 +129,24 @@ class AnthropicProvider(ProviderBase):
             raise ProviderError(f"Anthropic API error: {e}")
 
     def validate_api_key(self) -> bool:
+        """Validate Anthropic API key."""
         try:
             import os
             api_key = self.api_key or os.environ.get("ANTHROPIC_API_KEY")
             if not api_key:
                 return False
-            client = Anthropic(api_key=api_key)
+            _ = Anthropic(api_key=api_key)
             return True
         except Exception:
             return False
+
+    def list_models(self) -> list[str]:
+        """List available Anthropic models."""
+        return [
+            "claude-3-opus-20240229",
+            "claude-3-sonnet-20240229",
+            "claude-3-haiku-20240307",
+            "claude-2.1",
+            "claude-2.0",
+            "claude-instant-1.2",
+        ]