python-sdk.md

Develop MCP servers using the Python SDK by implementing JSON-RPC 2.0 handlers, defining tool functions with Pydantic validation, and choosing a transport mechanism—stdio, HTTP, or SSE. The SDK manages protocol compliance and server capability documentation automatically.

Python MCP supports stdio, HTTP, and SSE transports. Stdio works for local Claude integration; HTTP and SSE enable remote connections. Select based on deployment context and whether you need bidirectional streaming or request-response patterns.

Use Pydantic models to define and validate tool function inputs. Pydantic enforces type checking and schema constraints at the function boundary, ensuring only valid data reaches your business logic and catching errors early.

Yes. Python MCP servers support resource providers, tool function implementations, and multiple capabilities in one process. Document all capabilities in your server's response so clients discover available functionality.

Protocol violations break client communication and cause silent failures or connection drops. Test your implementation against the MCP specification, validate message structure and error responses, and use protocol debugging tools to verify compliance.

Authentication and authorization depend on your data sources and security requirements. Implement auth in your server-side tool handlers, not the MCP protocol layer, to protect sensitive resources accessed through Claude.