SEP-2133 Amendment: Add Experimental Extensions Framework#2158
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Thanks. Lets address Peder's comment
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This amendment adds support for experimental extensions, allowing Working Groups and Interest Groups to incubate extension ideas within the MCP organization before formal SEP submission. Key changes: - Add Experimental Extensions section with experimental-ext-<name> naming convention - Experimental extensions MUST be associated with a WG/IG - Any maintainer may create experimental repos while SEP is in draft - Graduation to official status follows standard SEP process - Update Abstract and Definition to acknowledge experimental extensions - Update Lifecycle/Creation to reference experimental incubation path
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…ol#2158) This amendment adds support for experimental extensions, allowing Working Groups and Interest Groups to incubate extension ideas within the MCP organization before formal SEP submission. Key changes: - Add Experimental Extensions section with experimental-ext-<name> naming convention - Experimental extensions MUST be associated with a WG/IG - Any maintainer may create experimental repos while SEP is in draft - Graduation to official status follows standard SEP process - Update Abstract and Definition to acknowledge experimental extensions - Update Lifecycle/Creation to reference experimental incubation path
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This PR amends SEP-2133 (Extensions) to add support for experimental extensions, allowing Working Groups and Interest Groups to incubate extension ideas within the MCP organization before formal SEP submission.
Related Discord discussion - https://discord.com/channels/1358869848138059966/1465676949476212737
Motivation and Context
The current SEP-2133 requires extensions to go through the full SEP process before getting a repository. This creates a chicken-and-egg problem: WGs/IGs need a place to collaborate and prototype, but can't get a repo until the SEP is accepted.
This amendment enables maintainers to create experimental extension repositories (e.g.,
experimental-ext-interceptors) for discovery, prototyping, and collaboration—all under neutral governance with anti-trust protection and IP clarity.This addresses feedback from the Financial IG and aligns with existing experimental repositories (
experimental-ext-interceptors,experimental-ext-variants).How Has This Been Tested?
This is a process/governance update to SEP-2133. The pattern has been validated by existing experimental repositories already in use by the Financial IG.
Breaking Changes
None. This is purely additive—existing official extension processes remain unchanged.
Types of changes
Checklist
Additional context
Per discussion among core maintainers, this is being submitted as a PR rather than a new SEP since it's a process update with broad alignment. Key changes:
Experimental Extensionssection withexperimental-ext-<name>naming convention