Feature Lifecycle and Deprecation Policy changedcommunity/feature-lifecycle
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1616This policy governs **features** of the MCP core specification: protocol
1717messages, capabilities, transports, schema types, and normative behavioral
1818requirements. The revision lifecycle of the specification document itself
19(Draft, Current, Final) is defined in the [versioning guide](/docs/learn/versioning).
19(Draft, Current, Final) is defined in the [versioning guide](/docs/learn/versioning.md).
2020
2121## Feature States
2222
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5252* or any other reasons the Core Maintainers deem appropriate.
5353
5454Deprecation is a specification change and therefore requires a SEP per the
55[SEP guidelines](/community/sep-guidelines). The deprecation SEP must:
55[SEP guidelines](/community/sep-guidelines.md). The deprecation SEP must:
5656
57571. Identify the feature by name and link to its definition in `schema.ts`
5858 (where applicable) and the specification prose.
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8585 removal.
8686
8787The feature becomes Deprecated when the revision carrying these changes is released
88and becomes the new Current revision (see [versioning guide](/docs/learn/versioning)).
88and becomes the new Current revision (see [versioning guide](/docs/learn/versioning.md)).
8989The minimum deprecation window is counted from that release.
9090
9191## The Deprecated Registry
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112112 logger).
113113
114114A Tier 1 SDK that consistently fails to surface a Deprecated feature is subject to the
115[Tier Relegation Process](/community/sdk-tiers#tier-relegation).
115[Tier Relegation Process](/community/sdk-tiers.md#tier-relegation).
116116
117117## Removing a Feature
118118
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132132security risk, meaning a vulnerability with a published security advisory or
133133documented in-the-wild exploitation for which no in-place mitigation exists.
134134Shortening the window requires Core Maintainer approval under the
135[governance decision process](/community/governance#decision-process), recorded
135[governance decision process](/community/governance.md#decision-process), recorded
136136in the deprecation SEP or, where the risk surfaces after that SEP is already
137137Final, in a short expedited-removal SEP that references it. The shortened
138138window must still provide at least ninety days between the feature becoming
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144144| - | - |
145145| Propose deprecation, extension, or restoration | Any contributor, per the SEP process |
146146| Sponsor | A Maintainer or Core Maintainer, per the SEP process |
147| Approve a deprecation SEP | Core Maintainers, per the [governance decision process](/community/governance#decision-process) |
148| Decide a removal during release preparation | Core Maintainers, per the [governance decision process](/community/governance#decision-process) |
149| Approve an extension or restoration SEP | Core Maintainers, per the [governance decision process](/community/governance#decision-process) |
150| Approve expedited removal | Core Maintainers, per the [governance decision process](/community/governance#decision-process) |
147| Approve a deprecation SEP | Core Maintainers, per the [governance decision process](/community/governance.md#decision-process) |
148| Decide a removal during release preparation | Core Maintainers, per the [governance decision process](/community/governance.md#decision-process) |
149| Approve an extension or restoration SEP | Core Maintainers, per the [governance decision process](/community/governance.md#decision-process) |
150| Approve expedited removal | Core Maintainers, per the [governance decision process](/community/governance.md#decision-process) |
151151
152152Lead Maintainers retain veto authority over each of the approvals
153above, per the [governance roles](/community/governance#roles) definition.
153above, per the [governance roles](/community/governance.md#roles) definition.
154154
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