Support for MCP Protocol Version 2025-11-25

[7nohe]

Describe the feature or problem you'd like to solve

Copilot CLI currently fails to connect to MCP servers with the error "Server's protocol version is not supported: 2025-11-25". The latest MCP specification has been updated to version 2025-11-25, but Copilot CLI does not support this version yet.

Proposed solution

Update Copilot CLI to support the latest MCP protocol version 2025-11-25. This would allow seamless integration with MCP servers that have upgraded to the current specification.

According to the official MCP specification (https://modelcontextprotocol.io/specification/versioning), version 2025-11-25 is the current protocol version.

Benefits:

• Enable users to connect to up-to-date MCP servers without version compatibility errors
• Ensure compliance with the latest MCP specification
• Improve interoperability with the broader MCP ecosystem

Example prompts or workflows

Users attempting to use Copilot CLI with MCP servers configured with the latest specification would be able to:

1. Connect to MCP servers running version 2025-11-25 without errors
2. Use @mcp commands to interact with tools and resources from updated MCP servers
3. Leverage the latest MCP features and improvements in their Copilot CLI workflows

Currently, users encounter the error message:

Server's protocol version is not supported: 2025-11-25

This prevents them from using any MCP servers that have updated to the current specification.

Additional context

References:

• Official MCP Specification: https://modelcontextprotocol.io/specification/versioning
• Current protocol version: 2025-11-25

Error message:

Server's protocol version is not supported: 2025-11-25

Expected behavior:
Copilot CLI should successfully connect to MCP servers using protocol version 2025-11-25, as it is the current official specification version.

[mlasevich]

Seems like a basic need.

[examon]

This should be resolved in current releases. The CLI's MCP SDK was upgraded to a version that includes protocol version 2025-11-25 in its supported versions, which addresses the Server's protocol version is not supported: 2025-11-25 error. Please update to the latest Copilot CLI release, and if you still see this issue there, feel free to reopen it.