Address PR review comments

- Move CachePoint imports to top of test files (test_bedrock.py, test_huggingface.py)
- Add documentation link for cacheable_types in anthropic.py

Addresses feedback from @DouweM in PR #3363

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: ronakrm

pydantic_ai_slim/pydantic_ai/models/anthropic.py

@@ -696,6 +696,7 @@ def _add_cache_control_to_last_param(params: list[BetaContentBlockParam]) -> Non
             )
 
         # Only certain types support cache_control
+        # See https://docs.anthropic.com/en/docs/build-with-claude/prompt-caching#what-can-be-cached
         cacheable_types = {'text', 'tool_use', 'server_tool_use', 'image', 'tool_result'}
         last_param = cast(dict[str, Any], params[-1])  # Cast to dict for mutation
         if last_param['type'] not in cacheable_types:

tests/models/test_bedrock.py

@@ -9,6 +9,7 @@
 
 from pydantic_ai import (
     BinaryContent,
+    CachePoint,
     DocumentUrl,
     FinalResultEvent,
     FunctionToolCallEvent,
@@ -1518,9 +1519,6 @@ async def test_cache_point_filtering():
     """Test that CachePoint is filtered out in Bedrock message mapping."""
     from itertools import count
 
-    from pydantic_ai import CachePoint, UserPromptPart
-    from pydantic_ai.models.bedrock import BedrockConverseModel
-
     # Test the static method directly
     messages = await BedrockConverseModel._map_user_prompt(UserPromptPart(content=['text', CachePoint()]), count())  # pyright: ignore[reportPrivateUsage]
     # CachePoint should be filtered out, message should still be valid

tests/models/test_huggingface.py

@@ -34,6 +34,7 @@
     Agent,
     AudioUrl,
     BinaryContent,
+    CachePoint,
     DocumentUrl,
     ImageUrl,
     ModelRequest,
@@ -1020,9 +1021,6 @@ async def test_hf_model_thinking_part_iter(allow_model_requests: None, huggingfa
 
 async def test_cache_point_filtering():
     """Test that CachePoint is filtered out in HuggingFace message mapping."""
-    from pydantic_ai import CachePoint, UserPromptPart
-    from pydantic_ai.models.huggingface import HuggingFaceModel
-
     # Test the static method directly
     msg = await HuggingFaceModel._map_user_prompt(UserPromptPart(content=['text', CachePoint()]))  # pyright: ignore[reportPrivateUsage]