SDK Working Group Charter

Documentation Index

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Group Type

Working Group

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Mission Statement

The SDK Working Group exists to keep the official MCP SDKs consistent, conformant, and current with the specification. It coordinates implementation of new protocol versions across languages, governs the SDK Tiering System, and establishes shared design patterns where sensible, so that developers get a coherent experience across SDKs while each remains idiomatic to its language.

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Scope

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In Scope

• SDK Tiering: Operating the SDK Tiering System, including reviewing tier advancement requests, applying relegation criteria, and maintaining the published tier assignments.
• Official SDK Roster: Evaluating proposals to add new official SDKs or retire existing ones.
• Release Coordination: Aligning Tier-1 SDK release plans with specification version dates so that protocol features land in SDKs on the timelines their tier requires.
• Cross-SDK Design Guidance: Recommending common patterns for SDK API surface, versioning, deprecation, error handling, and extension packaging, so that SDKs remain recognisably similar across languages while staying idiomatic.
• Conformance Integration: Working with the Conformance Testing project to ensure each official SDK runs the conformance suite and publishes results.
• Maintainer Coordination: Providing a forum for per-language SDK maintainers to share implementation experience and surface specification ambiguities back to Core Maintainers.

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Out of Scope

• Per-SDK day-to-day maintenance: Issue triage, PR review, and releases for an individual SDK remain the responsibility of that SDK’s maintainers as listed in MAINTAINERS.md.
• Specification authorship: Protocol changes are proposed through the SEP process and owned by the relevant working group or Core Maintainers. The SDK WG implements accepted SEPs; it does not own spec sections.
• Conformance test authoring: The conformance test suite itself is owned by the Conformance Testing project.
• Third-party and community SDKs: SDKs outside the modelcontextprotocol organization are not governed by this group.

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Related Groups

• Transports WG: Transport implementations are a substantial part of every SDK. The SDK WG coordinates with the Transports WG on rollout sequencing when transport SEPs land.
• Conformance Testing: Tier assignments depend on conformance scores. The SDK WG consumes conformance results and feeds back gaps in test coverage.
• All specification-producing WGs: The SDK WG is a downstream consumer of accepted SEPs and coordinates reference-implementation timing with the originating group.

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Leadership

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Authority & Decision Rights

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Membership

WG Members are the maintainers of each official SDK as recorded in MAINTAINERS.md and the corresponding roles in modelcontextprotocol/access. Maintainers of any official SDK are WG Members by default.

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Operations

Communication happens in the #general-sdk-dev Discord channel and the SDK Working Group category in GitHub Discussions.

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Deliverables & Success Metrics

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Active Work Items

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Success Criteria

• All official SDKs have a published tier and a passing conformance run on their default branch.
• Tier-1 SDKs ship support for each released specification version within the timeline their tier requires.
• Tier advancement and relegation decisions are recorded with rationale in GitHub Discussions.

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Changelog