Mercurius · GraphQL Specification
Mercurius GraphQL
Mercurius is a GraphQL adapter for Fastify. It exposes a GraphQL endpoint that handles queries, mutations, and subscriptions over HTTP and WebSocket.
Overview
Mercurius GraphQL is a GraphQL API specification published by Mercurius on the APIs.io network.
Mercurius is a GraphQL adapter for Fastify. It exposes a GraphQL endpoint that handles queries, mutations, and subscriptions over HTTP and WebSocket.
The specification includes 3 reference links.
Tagged areas include Fastify, Node.js, Federation, WebSocket, and Open-Source.
Endpoint
References
- GitHub https://github.com/mercurius-js/mercurius
- npm https://www.npmjs.com/package/mercurius
- Documentation https://mercurius.dev/
Work with this as data
Every GraphQL schema here is available over the APIs.io API and to AI agents over MCP.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for graphql
4 MCP tools reach this
find_graphqlBrowse and filter every GraphQL schema in the catalog.apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.resolveTurn a domain, URL or GitHub org into the provider it belongs to.find_cohortsEvery scored population of providers in the catalog.
Call it yourself
curl for this page
This GraphQL schema
curl "https://apis.io/api/v1/graphql/mercurius-graphql"
All graphql
curl "https://apis.io/api/v1/graphql?limit=25"
Discovery needs no key. Ratings and market analysis are Pro.