omcp
A community-driven, permissionless hard fork of the Model Context Protocol specification, developed openly on GitHub and decided on technical merit rather than closed-door approval.
omcp is wire-compatible with the broader MCP ecosystem: its schema field names, method names and protocol version identifiers are unchanged, so existing MCP clients, servers and SDKs interoperate with it without modification. The fork changes how the specification is developed and governed, not what goes over the wire.
It only ever adds: new capability arrives as an extension or an optional element that an implementation which does not understand it can ignore; a change that alters or removes something MCP already defines is out of scope regardless of its merits.
The repository holds the specification, its TypeScript-first protocol schema, also published as JSON Schema, and its documentation, published as HTML and PDF and rebuilt from the repository on every change to the main branch.