Launched in preview in September 2025 by the MCP open-source community (with Anthropic, GitHub, PulseMCP and Microsoft involved), the registry is the single source of truth that downstream catalogs — including the GitHub MCP Registry — build on. It passed several thousand listed servers within its first year.
Publishing is namespace-verified: io.github.* names require GitHub login (or GitHub Actions OIDC, which lets CI publish with zero stored secrets), and custom reverse-DNS namespaces are verified via DNS or HTTP. Each entry is a server.json describing where the server lives and how to run or reach it. For agents, the registry is becoming what package registries were for code: the default place to resolve trusted tools.
Verify a namespace (easiest: io.github.you via GitHub auth, or OIDC from GitHub Actions), write a server.json describing your server, and publish with the mcp-publisher CLI. Then make sure the server itself passes a health check — clients skip broken servers.