MCP

TestPion is a full MCP client built on the official TypeScript SDK. MCP servers are listed in the MCP servers section of the Collections explorer (the one sidebar of the request editors); a server opens in its own tab of the MCP view.

• Connect over stdio, Streamable HTTP or legacy SSE, or serve a mock from a YAML file.
• Discover tools, resources, resource templates and prompts.
• Run tools from forms generated from their JSON Schema, and save calls as regression tests (Save as test…).
• Answer a server's elicitation, sampling and roots requests.
• Debug with a timeline of every JSON-RPC message.

Transport handling is isolated from the domain model: a tracing decorator wraps whichever transport is used.