SDK Working Group Meeting Notes - Feb 11, 2026 #2237

Key Topics Discussed

1. Tiering Assessment Tool

• A new script and agent skill was added to the conformance test repo to help SDK maintainers self-assess against tiering requirements
  • Runs through issues, labels, and documentation files (roadmap, dependency policy, versioning policy, etc.)
  • Outputs a structured report indicating gaps
• The tool is a guidance aid, not a final determination — actual tier assignment requires human review with links to evidence for each requirement
• All SDK maintainers asked to try the tool and provide feedback

2. Tiering Display Page

• A mockup was shared of a new page planned for the Model Context Protocol repo listing all SDKs with tier adherence broken down by category
  • Not a simple pass/fail — shows granular detail on which categories meet which tier requirements
  • To achieve an overall tier (e.g., Tier 1), all minimum requirements for that tier must be met

3. Java SDK Special Case

• Dariusz raised that the Java SDK is designed to be pluggable due to the fragmented Java ecosystem (e.g., no official JDK OAuth libraries)
  • Requested separate entries on the tiering page for different framework integrations (e.g., "Java SDK with Spring," "Java SDK with Micronaut")
• Agreed: Java SDK will be listed at its highest achieved tier with an asterisk noting which plugin/framework combination achieves that tier

4. Tiering Submission Process

• A new (initially hidden) page will be created on the Model Context Protocol repo
• SDK maintainers submit PRs filling out their tier table with their desired tier
  • PR descriptions must include links to artifacts/evidence for each requirement (documentation links, conformance suite runs, issue triage evidence, etc.)
• @felixweinberger and @pcarleton will review; broader working group also invited to review submissions
• Upon approval, the SDK's tier is officially published
• The TypeScript SDK will aim to make a first example tier submission for others to follow in structure

5. Conformance Suite Versioning

• Maciek asked how the conformance test version would be updated over time
  • Version for the February 23rd launch is 0.11
  • No surprise updates — next major update aligns with the next spec release
  • Bug fixes to the conformance suite itself will not change tier requirements
  • If a rerun later causes a tier change, a grace period (e.g., two weeks) will be provided to fix issues

6. Tiering Purpose

• Marcelo asked why SDKs should care about tiers
  • Tiers signal reliability and maintenance quality to SDK consumers, especially enterprise customers
  • SDKs must be at least Tier 2 to be listed in the official MCP org — participation is not mandatory for SDKs that don't want to be listed

7. Protocol Schema PR

• A PR was flagged tightening the protocol schema from flexible TypeScript objects to typed JSON
  • All SDK maintainers asked to review for potential impact on their SDKs

8. V2 SDKs (Python & TypeScript)

• Maciek asked about V2 plans
  • Motivated by: accumulated breaking changes, architecture simplification, deprecated feature removal, and anticipated breaking changes from upcoming transport rework (stateless protocol, potential gRPC support)
  • No explicit goal to make SDKs consistent across languages — spec compliance via the conformance suite is what matters
• Typescript and Python have projects for tracking:
  • https://github.com/orgs/modelcontextprotocol/projects/31
  • https://github.com/orgs/modelcontextprotocol/projects/30

9. Draft Conformance Tests for SEPs

• Wils suggested a "draft" section in the conformance suite for in-progress SEPs
  • Already supported via test suites (e.g., a "pending SEPs" suite)
  • Recommended coordinating with @pcarleton

Action Items

1. @felixweinberger: Create the tiering page on the Model Context Protocol repo (initially hidden before Feb 23).
2. @felixweinberger: Submit the TypeScript SDK tiering PR as a first example for others to follow in structure.
3. @felixweinberger: Rework the tiering page mockup to accommodate the Java SDK's pluggable architecture (separate entries per framework integration, asterisk notation).
4. All SDK Maintainers: Try out the tiering assessment script/skill and provide feedback if it doesn't work well for their repo structure.
5. All SDK Maintainers: Review the protocol schema PR (tightening from objects to typed JSON) and assess impact.
6. All SDK Maintainers: Prepare tiering PR submissions with evidence/artifacts for desired tier by February 23rd.
7. Wils: Coordinate with @pcarleton on adding refresh token SEP conformance tests to the suite (as a draft/pending suite).