Changelog changedspecification/draft/changelog
Nearest release: v2.1.319, published 14 hours before upstream edited the page. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.
Upstream edited this page at 6 Nov 2026 15:57 UTC, give or take a minute or two: the time comes from Anthropic’s own sitemap rather than from a commit. This site recorded the change at 6 Nov 2026 16:07 UTC.
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## Other schema changes
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33Changes since the most recent release will accumulate here.
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5## Other schema changes
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71. Restore the optional `_meta` field on `CreateMessageRequestParams`, `ElicitRequestFormParams`, `ElicitRequestURLParams`, `ElicitResult`, and `ListRootsResult`. It was unintentionally dropped in 2026-07-28 when these types stopped extending `TaskAugmentedRequestParams` and `Result`, leaving `ListRootsRequest` as the only input request that could carry `_meta` ([#3468](https://github.com/modelcontextprotocol/modelcontextprotocol/issues/3468)).
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