[Repo] modelcontextprotocol/experimental-ext-variants: Status: Experimental. This repository provides a multi-language reference implementation of the variants proposal for the Model Context Protocol (MCP), as described in SEP-2053.

This experimental repository provides a multi-language reference implementation of the variants proposal for the Model Context Protocol (MCP), as specified in SEP-2053. It demonstrates how to extend MCP with variant support across multiple programming languages. The project is actively maintained with recent updates and serves as a blueprint for implementing protocol extensions.

Key Points

• •Experimental implementation of MCP variants proposal (SEP-2053) for protocol extensibility
• •Multi-language reference implementation enabling cross-language compatibility
• •Demonstrates variant patterns for extending Model Context Protocol capabilities
• •Active development with recent updates (last pushed March 2026)
• •Serves as reference architecture for MCP extension implementations
• •Covers variant proposal specification and practical code examples
• •Supports multiple programming languages for variant implementation patterns

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