Tasks moves to a new Tasks and Events working group

official extension. Extensions are always opt-in: a client only uses an extension if both client and server declare support in the

extensions field of their capabilities.

This list is maintained by the community. If you notice any inaccuracies or would like to add or update information, please

submit a pull request.

Extension overview #

Support matrix #

Auth extension support (OAuth Client Credentials and Enterprise-Managed Authorization) is tracked separately from the core MCP authorization features (DCR, CIMD). Check each extension’s specification and the

ext-auth repositoryfor the latest implementation status.

Adding extension support to your client #

If you’re building an MCP client and want to implement extension support:
1. Review the extension specification (e.g., in the [ext-auth](https://github.com/modelcontextprotocol/ext-auth) or[ext-apps](https://github.com/modelcontextprotocol/ext-apps) repository)

2. Declare support in the extensions field of theio.modelcontextprotocol/clientCapabilities your client sends in each request’s_meta , and read the server’sextensions from itsserver/discover response
3. Implement the extension’s protocol requirements
4. Submit a pull request to update this matrix

Extensions Overviewfor details on the capability negotiation mechanism.