MCP (Model Context Protocol)
MCP (Model Context Protocol) is an open protocol that lets an AI application use outside tools and data through a standard client and server interface. Both stores build on MCP: Apps SDK apps and Claude connectors are MCP servers, and 727 MCP servers sit behind live listings on October 13, 2026.
- Servers behind listings
- 727
- Open
- 105tools listed without sign-in
- MCP dataset
- 425 open serversevery store we track
- Tools in the dataset
- 7,777every store we track
More from our data
ChatGPT publishes no server URLs, so every one of them is linked from a Claude listing. 105 of them list their tools without a sign-in.
Our wider MCP dataset is the 425 open servers we track across every store, not only the 105 behind ChatGPT and Claude listings, with 7,777 tools. In it, 94% of open servers support MCP protocol version 2025-06-18; 20 answer with an older version and 5 with a later one.
Tools are visible for under 3% of store listings, so read every tool-level number as a sample. The MCP tool design census shows what that sample looks like.