Update cohere and MCP, add support for MCP ResourceLink returned from tools (#2094)

Co-authored-by: Douwe Maan <douwe@pydantic.dev>

Author: medaminezghal

docs/mcp/server.md

@@ -117,7 +117,10 @@ async def sampling_callback(
         SamplingMessage(
             role='user',
             content=TextContent(
-                type='text', text='write a poem about socks', annotations=None
+                type='text',
+                text='write a poem about socks',
+                annotations=None,
+                meta=None,
             ),
         )
     ]

pydantic_ai_slim/pydantic_ai/mcp.py

@@ -151,7 +151,7 @@ async def direct_call_tool(
             except McpError as e:
                 raise exceptions.ModelRetry(e.error.message)
 
-        content = [self._map_tool_result_part(part) for part in result.content]
+        content = [await self._map_tool_result_part(part) for part in result.content]
 
         if result.isError:
             text = '\n'.join(str(part) for part in content)
@@ -262,8 +262,8 @@ async def _sampling_callback(
             model=self.sampling_model.model_name,
         )
 
-    def _map_tool_result_part(
-        self, part: mcp_types.Content
+    async def _map_tool_result_part(
+        self, part: mcp_types.ContentBlock
     ) -> str | messages.BinaryContent | dict[str, Any] | list[Any]:
         # See https://github.com/jlowin/fastmcp/blob/main/docs/servers/tools.mdx#return-values
 
@@ -285,18 +285,29 @@ def _map_tool_result_part(
             )  # pragma: no cover
         elif isinstance(part, mcp_types.EmbeddedResource):
             resource = part.resource
-            if isinstance(resource, mcp_types.TextResourceContents):
-                return resource.text
-            elif isinstance(resource, mcp_types.BlobResourceContents):
-                return messages.BinaryContent(
-                    data=base64.b64decode(resource.blob),
-                    media_type=resource.mimeType or 'application/octet-stream',
-                )
-            else:
-                assert_never(resource)
+            return self._get_content(resource)
+        elif isinstance(part, mcp_types.ResourceLink):
+            resource_result: mcp_types.ReadResourceResult = await self._client.read_resource(part.uri)
+            return (
+                self._get_content(resource_result.contents[0])
+                if len(resource_result.contents) == 1
+                else [self._get_content(resource) for resource in resource_result.contents]
+            )
         else:
             assert_never(part)
 
+    def _get_content(
+        self, resource: mcp_types.TextResourceContents | mcp_types.BlobResourceContents
+    ) -> str | messages.BinaryContent:
+        if isinstance(resource, mcp_types.TextResourceContents):
+            return resource.text
+        elif isinstance(resource, mcp_types.BlobResourceContents):
+            return messages.BinaryContent(
+                data=base64.b64decode(resource.blob), media_type=resource.mimeType or 'application/octet-stream'
+            )
+        else:
+            assert_never(resource)
+
 
 @dataclass
 class MCPServerStdio(MCPServer):

pydantic_ai_slim/pydantic_ai/models/cohere.py

@@ -38,15 +38,15 @@
         AssistantChatMessageV2,
         AsyncClientV2,
         ChatMessageV2,
-        ChatResponse,
         SystemChatMessageV2,
-        TextAssistantMessageContentItem,
+        TextAssistantMessageV2ContentItem,
         ToolCallV2,
         ToolCallV2Function,
         ToolChatMessageV2,
         ToolV2,
         ToolV2Function,
         UserChatMessageV2,
+        V2ChatResponse,
     )
     from cohere.core.api_error import ApiError
     from cohere.v2.client import OMIT
@@ -164,7 +164,7 @@ async def _chat(
         messages: list[ModelMessage],
         model_settings: CohereModelSettings,
         model_request_parameters: ModelRequestParameters,
-    ) -> ChatResponse:
+    ) -> V2ChatResponse:
         tools = self._get_tools(model_request_parameters)
         cohere_messages = self._map_messages(messages)
         try:
@@ -185,7 +185,7 @@ async def _chat(
                 raise ModelHTTPError(status_code=status_code, model_name=self.model_name, body=e.body) from e
             raise  # pragma: no cover
 
-    def _process_response(self, response: ChatResponse) -> ModelResponse:
+    def _process_response(self, response: V2ChatResponse) -> ModelResponse:
         """Process a non-streamed response, and prepare a message to return."""
         parts: list[ModelResponsePart] = []
         if response.message.content is not None and len(response.message.content) > 0:
@@ -227,7 +227,7 @@ def _map_messages(self, messages: list[ModelMessage]) -> list[ChatMessageV2]:
                         assert_never(item)
                 message_param = AssistantChatMessageV2(role='assistant')
                 if texts:
-                    message_param.content = [TextAssistantMessageContentItem(text='\n\n'.join(texts))]
+                    message_param.content = [TextAssistantMessageV2ContentItem(text='\n\n'.join(texts))]
                 if tool_calls:
                     message_param.tool_calls = tool_calls
                 cohere_messages.append(message_param)
@@ -294,7 +294,7 @@ def _map_user_message(cls, message: ModelRequest) -> Iterable[ChatMessageV2]:
                 assert_never(part)
 
 
-def _map_usage(response: ChatResponse) -> usage.Usage:
+def _map_usage(response: V2ChatResponse) -> usage.Usage:
     u = response.usage
     if u is None:
         return usage.Usage()

pydantic_ai_slim/pyproject.toml

@@ -63,7 +63,7 @@ dependencies = [
 logfire = ["logfire>=3.11.0"]
 # Models
 openai = ["openai>=1.92.0"]
-cohere = ["cohere>=5.13.11; platform_system != 'Emscripten'"]
+cohere = ["cohere>=5.16.0; platform_system != 'Emscripten'"]
 vertexai = ["google-auth>=2.36.0", "requests>=2.32.2"]
 google = ["google-genai>=1.24.0"]
 anthropic = ["anthropic>=0.52.0"]
@@ -77,7 +77,7 @@ tavily = ["tavily-python>=0.5.0"]
 # CLI
 cli = ["rich>=13", "prompt-toolkit>=3", "argcomplete>=3.5.0"]
 # MCP
-mcp = ["mcp>=1.9.4; python_version >= '3.10'"]
+mcp = ["mcp>=1.10.0; python_version >= '3.10'"]
 # Evals
 evals = ["pydantic-evals=={{ version }}"]
 # A2A

tests/assets/product_name.txt

@@ -0,0 +1 @@
+Pydantic AI