A configurable mock MCP server with a live web UI that lets developers define tools, point their MCP clients at it, and watch every JSON-RPC message in both directions to debug client behavior such as initialization, tool list refreshes, and error handling.
A mock MCP server for testing MCP client implementations and development workflows. Supports tools, prompts, and resources across multiple transport protocols (stdio, HTTP, SSE).
A test MCP server that exercises all protocol features including tools, resources, prompts, and sampling to help client builders validate implementations.