Open Source

mcp-query

A data layer for the Model Context Protocol

A reactive, cached client for MCP servers, plus the governance, testing, and fixture tooling built around it — same shape as the GraphQL world, but for MCP.

mcp-query brings the ergonomics of the GraphQL tooling ecosystem to the Model Context Protocol. At its core is a reactive, cached MCP client in the shape of TanStack Query — subscriptions, invalidation, and optimistic updates over any MCP server.

Around that core sits the operational tooling real deployments need: a policy gateway for governance, linting and drift detection for server schemas, record/replay fixtures for offline testing, and one CLI — mcpq — that works across every tool.

  • TanStack-Query-style reactive cache
  • Policy gateway, lint, and drift detection
  • Record/replay for offline testing
  • One CLI (mcpq) over every tool