mcpdesc · ObjectIsAdvantag · Sep 7, 2026 · Sep 7, 2026
diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
@@ -39,6 +39,9 @@
 - Treat core snapshot support as operation-specific. Adding a selector requires
   an explicit disposition for every selector-sensitive public operation and an
   updated exhaustive support-contract test.
+- Treat active snapshot retention as an explicit lifecycle decision. Retired
+  selectors leave current registries, declarations, bundles, and tarballs while
+  their immutable source and fixtures remain in Git and older package releases.
 
 ## Documentation Delineation
 

diff --git a/.github/skills/release-assessment/SKILL.md b/.github/skills/release-assessment/SKILL.md
@@ -11,7 +11,8 @@ license: Apache-2.0
 
 ## Workflow
 
-1. Read `AGENTS.md`, `CHANGELOG.md`, `ROADMAP.md`, and `RELEASING.md`.
+1. Read `AGENTS.md`, `CHANGELOG.md`, both package changelogs, `ROADMAP.md`, and
+   `RELEASING.md`.
 2. Fetch tags and the current main branch without changing the worktree:
 
    ```bash

diff --git a/.github/skills/validator-snapshot-intake/SKILL.md b/.github/skills/validator-snapshot-intake/SKILL.md
@@ -61,6 +61,9 @@ informational.
 ## Boundaries
 
 - Snapshot approval does not authorize npm publication.
+- Treat the source bundle and its `manifest.json` as disposable intake inputs.
+  Do not copy or retain them under `packages/validator/`; imported runtime and
+  fixture bytes are protected by `snapshot-integrity.json`.
 - Do not require a sibling specification checkout in routine tests or CI.
 - Do not overwrite, alias, or silently retarget an existing selector.
 - Record AI assistance in the pull request.
diff --git a/AGENTS.md b/AGENTS.md
@@ -8,14 +8,15 @@ validation without creating a second source of normative specification text.
 ## Starting a work session
 
 - Work from this repository, not from a consumer or specification repository.
-- Read `README.md`, `CHANGELOG.md`, and `ROADMAP.md` before selecting work.
+- Read `README.md`, `CHANGELOG.md`, the relevant package changelog, and
+  `ROADMAP.md` before selecting work.
 - Inspect the current branch and worktree before editing; do not assume roadmap
   items have been approved or started.
 - Confirm the next milestone with the maintainer when it requires publication, a
   new public operation, a cross-repository integration, or a package-boundary
   decision.
-- Keep `CHANGELOG.md` and `ROADMAP.md` synchronized with delivered behavior and
-  approved sequencing.
+- Keep the relevant package changelog and `ROADMAP.md` synchronized with
+  delivered behavior and approved sequencing.
 
 ## Ownership boundaries
 
@@ -42,6 +43,10 @@ validation without creating a second source of normative specification text.
   never require a sibling specification checkout in routine CI.
 - Existing directories under `packages/validator/src/snapshots/` and
   `packages/validator/test/snapshots/` are immutable. Add sibling selectors.
+- Runtime and package support is an explicit lifecycle decision. Retiring a
+  selector removes it from registries, declarations, generated bundles, and
+  package contents without deleting or modifying its historical source and
+  fixtures; consumers can pin the older immutable package release.
 - A maintainer may approve an additive tooling-metadata correction to a
   published snapshot implementation only when its schema, conformance results,
   diagnostics, and frozen fixtures remain unchanged. Record each exception in

diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,190 +1,10 @@
-# Changelog
+# Changelogs
 
-All notable changes to this repository are documented here.
+The packages in this repository are versioned and released independently. See
+the changelog for the package you consume:
 
-## [0.9.0] - 2026-09-07
+- [`@mcpdesc/core`](packages/core/CHANGELOG.md)
+- [`@mcpdesc/validator`](packages/validator/CHANGELOG.md)
 
-### Added
-
-- Added MCP Description `0.8.0-rc.3` validator support and core support for
-  projection, merge, declaration selection, component reference resolution, and
-  migration from 0.7.0.
-- Added RC.2 component reference resolution with deterministic terminal-target
-  provenance.
-
-### Changed
-
-- Snapshot integrity now protects package-owned selector bytes without binding
-  validation behavior to immutable specification repository documentation or
-  source commits.
-
-## [0.8.1] - 2026-09-05
-
-### Added
-
-- `migrateMcpDescription07ToRc2`, an exact-target migration from
-  caller-validated MCP Description 0.7.0 documents with RC.2 result validation
-  and conversion reports.
-
-### Fixed
-
-- npm publishing workflows use OIDC trusted publishing without token-oriented
-  registry configuration, and validator tags no longer trigger the core publish
-  workflow.
-
-## [0.8.0] - 2026-09-04
-
-### Added
-
-- Immutable MCP Description `0.8.0-rc.2` validator and core selector support,
-  with pinned extension catalogue metadata and manifest-verified provenance.
-- `mergeEffectiveProtocolViews` and semantic-equivalence support for validated
-  protocol views, including pre-standard extension-map round trips.
-
-### Changed
-
-- RC.2 Effective Protocol View projection preserves structurally valid server
-  extension maps for pre-2026 revisions. Validator handling is compatibly
-  relaxed from an error to `extensions-not-supported-by-version` warnings;
-  client requirements remain strict and earlier selectors remain immutable.
-
-## [0.7.0] - 2026-09-03
-
-### Added
-
-- `resolveMcpDescriptionComponentReferences` in the root and CSP-safe
-  `@mcpdesc/core/components` entry points for validated RC.1 component
-  resolution, with deterministic authored-to-terminal provenance and typed
-  component references and registries.
-
-### Changed
-
-- Core now pins `@mcpdesc/validator` `0.8.0` and reaches the snapshot-owned
-  resolver only through its CSP-safe standalone entry.
-
-## [0.6.1] - 2026-09-02
-
-### Changed
-
-- Core now pins `@mcpdesc/validator` `0.7.1`, whose package documentation and
-  npm homepage identify the validator's purpose and package directory more
-  clearly.
-
-## [0.6.0] - 2026-09-02
-
-### Added
-
-- `@mcpdesc/validator` as an independently versioned workspace package,
-  preserving its immutable snapshots, frozen fixtures, public APIs, and
-  strict-CSP browser contracts from `0.6.0`.
-
-### Changed
-
-- Core development now consumes the repository-owned validator `0.7.0` workspace
-  package through the existing standalone entry.
-
-## [0.5.0] - 2026-09-02
-
-### Added
-
-- Optional RC.1 migration protocol defaults with snapshot validation and a
-  stable `migration-default-protocol-version` warning when applied.
-- Deterministic, JSON-compatible conversion reports for successful, warned, and
-  failed migrations, plus pretty-printed report serialization.
-
-## [0.4.0] - 2026-09-01
-
-### Added
-
-- Immutable MCP Description `0.8.0-rc.1` constants and provenance metadata.
-- `migrateMcpDescription07ToRc1`, a dedicated migration that emits and validates
-  the exact RC.1 schema snapshot.
-
-### Changed
-
-- Effective Protocol View projection and declaration selection now accept exact
-  Draft 4 or RC.1 selectors while preserving all published Draft 4 behavior.
-
-## [0.3.0] - 2026-09-01
-
-### Added
-
-- CSP-safe `@mcpdesc/core/documents` and `@mcpdesc/core/selection` subpath
-  exports, with browser checks that keep document parsing validator-free.
-
-### Changed
-
-- Validator-backed operations now use `@mcpdesc/validator/standalone` 0.5.0 to
-  avoid runtime code generation under strict browser CSP.
-
-## [0.2.0] - 2026-08-31
-
-### Added
-
-- `parseMcpDescriptionSource` and `serializeMcpDescription`, browser-safe pure
-  operations for source-aware JSON/YAML parsing and deterministic output without
-  host I/O.
-- JSON-compatible YAML enforcement for finite numbers, string mapping keys,
-  plain values, and acyclic structures.
-- Strict JSON enforcement for unique object keys and finite numbers.
-- `selectMcpDescriptionDeclarations`, a pure Draft 4 operation for selecting
-  tools, resources, resource templates, and prompts by their normative
-  identities while retaining scoped variants and omitting empty collections.
-- Source/result validation, structured diagnostics, immutability tests, browser
-  bundling, tarball checks, and isolated-consumer coverage for declaration
-  selection.
-- `migrateMcpDescription07ToDraft4`, a pure migration for caller-validated 0.7.0
-  documents with deterministic inline-security extraction, empty collection
-  normalization, generated-name diagnostics, and Draft 4 result validation.
-- A maintainer-controlled release procedure covering tarball review, version and
-  tag consistency, first-publication bootstrap, trusted npm publishing,
-  provenance, and post-publication verification.
-- A tag-triggered GitHub Actions workflow that runs the full validation suite
-  and publishes `@mcpdesc/core` with npm provenance support.
-
-### Changed
-
-- Contribution guidance now uses lockfile-exact installation and links to the
-  release procedure.
-- The `Validate` workflow is enabled as a required check for `main`.
-- Future npm releases use GitHub Actions trusted publishing without a stored npm
-  token.
-
-## [0.1.0] - 2026-08-31
-
-Initial experimental package baseline, published manually to npm after local
-tarball verification. The corresponding Git tag has not yet been created.
-
-### Added
-
-- `@mcpdesc/core`, a TypeScript ESM package for Node.js 22 or later and browser
-  bundlers.
-- `projectEffectiveProtocolView`, a pure operation that projects an MCP
-  Description `0.8.0-draft.4` document to one declared MCP protocol revision.
-- Projection across transports, capabilities, tools, resources, resource
-  templates, prompts, and nested elicitation declarations while preserving
-  document-wide content and reusable components.
-- Validator-backed source and result validation with structured, phase-aware,
-  deduplicated diagnostics.
-- Immutable Draft 4 snapshot metadata sourced from `@mcpdesc/validator@0.4.0`,
-  including the schema URI, snapshot tag, schema digest, and supported protocol
-  revisions.
-- Focused tests for scope inheritance, omission, nested projection,
-  immutability, idempotence, diagnostics, and snapshot provenance.
-- Type checking, formatting, browser bundling, exact package-content checks, and
-  isolated tarball consumer verification in the local and CI validation
-  workflow.
-- Apache-2.0 licensing, provenance, contribution guidance, and repository
-  instructions for coding assistants.
-
-[Unreleased]: https://github.com/mcpdesc/core/compare/v0.8.1...HEAD
-[0.8.1]: https://github.com/mcpdesc/core/compare/v0.8.0...v0.8.1
-[0.8.0]: https://github.com/mcpdesc/core/compare/v0.7.0...v0.8.0
-[0.7.0]: https://github.com/mcpdesc/core/compare/v0.6.1...v0.7.0
-[0.6.1]: https://github.com/mcpdesc/core/compare/v0.6.0...v0.6.1
-[0.6.0]: https://github.com/mcpdesc/core/compare/v0.5.0...v0.6.0
-[0.5.0]: https://github.com/mcpdesc/core/compare/v0.4.0...v0.5.0
-[0.4.0]: https://github.com/mcpdesc/core/compare/v0.3.0...v0.4.0
-[0.3.0]: https://github.com/mcpdesc/core/compare/v0.2.0...v0.3.0
-[0.2.0]: https://github.com/mcpdesc/core/compare/v0.1.0...v0.2.0
-[0.1.0]: https://github.com/mcpdesc/core/releases/tag/v0.1.0
+Repository-only maintenance that does not affect a published package is tracked
+in Git history and pull requests rather than a shared release changelog.
diff --git a/README.md b/README.md
@@ -10,18 +10,18 @@ The repository contains two independently versioned packages:
   MCP Description snapshots, including strict-CSP browser entry points.
 
 The package parses and serializes JSON or YAML source text, migrates validated
-MCP Description 0.7.0 values to exact Draft 4, RC.1, RC.2, or RC.3 snapshots
-with stable conversion reports, projects and merges Effective Protocol Views
-through RC.3, and selects declaration subsets by normative identity. Validator
-snapshots provide the conformance authority for those operations. Published
-package operations perform no network or file access and support browser
-bundlers.
+MCP Description 0.7.0 values to exact RC.2 or RC.3 snapshots with stable
+conversion reports, projects and merges Effective Protocol Views, and selects
+declaration subsets by normative identity. RC.2 is deprecated but remains
+operational during migration to RC.3. Validator snapshots provide the
+conformance authority for those operations. Published package operations perform
+no network or file access and support browser bundlers.
 
 APIs remain experimental while MCP Description 0.8 is a community working draft.
 npm package versions, MCP Description versions, immutable snapshot selectors,
 schema identities, and MCP protocol revisions are separate version axes.
 
-See [CHANGELOG.md](CHANGELOG.md) for delivered behavior and
+See the [package changelog index](CHANGELOG.md) for delivered behavior and
 [ROADMAP.md](ROADMAP.md) for the staged next steps and deferred decisions. See
 [RELEASING.md](RELEASING.md) for the maintainer-controlled release process.
 

diff --git a/RELEASING.md b/RELEASING.md
@@ -19,8 +19,9 @@ the guarded `release:check` and `release:tag` scripts below.
   equivalent SSH URL for that repository.
 - Confirm that the package version is unused on npm and matches its intended Git
   tag: `v<version>` for core or `validator-v<version>` for validator.
-- Record user-visible changes in `CHANGELOG.md` and keep `ROADMAP.md` aligned
-  with the work actually delivered.
+- Record user-visible changes in `packages/core/CHANGELOG.md` or
+  `packages/validator/CHANGELOG.md` and keep `ROADMAP.md` aligned with the work
+  actually delivered.
 
 ## Prepare and inspect
 
@@ -100,6 +101,6 @@ npm audit signatures
 ```
 
 Confirm the npm provenance links to the expected GitHub repository, workflow,
-tag, and commit. Create the corresponding GitHub release from the changelog,
-then update `CHANGELOG.md` and `ROADMAP.md` if the published outcome differs
-from the release preparation.
+tag, and commit. Create the corresponding GitHub release from the package
+changelog, then update that changelog and `ROADMAP.md` if the published outcome
+differs from the release preparation.
diff --git a/ROADMAP.md b/ROADMAP.md
@@ -43,6 +43,8 @@ repository.
 - [x] Expose reusable-component resolution as a separate RC.1, RC.2, and RC.3
       pure operation with deterministic terminal-target provenance and existing
       unresolved-reference diagnostics.
+- [x] Narrow current runtime and package support to RC.2 and RC.3, deprecate
+      RC.2, and retain retired snapshot artifacts as repository history.
 - Add normalization or comparison operations only where multiple consumers
   demonstrate the same requirement.
 
@@ -54,10 +56,10 @@ normative schema applies.
 
 - Adopt shared operations in the editor and Inspector where they replace
   duplicated semantic logic.
-- Add support for later immutable MCP Description snapshots without silently
-  changing behavior for existing selectors. Record every selector-sensitive
-  operation as supported or intentionally unsupported and keep the exhaustive
-  support-contract test synchronized with that decision.
+- Add later immutable MCP Description snapshots through an explicit active
+  support decision. Record every selector-sensitive operation as supported or
+  intentionally unsupported, retire selectors from current packages when their
+  transition window closes, and keep the exhaustive support contract current.
 - Revisit package boundaries as concrete parser, serialization, or capture
   requirements emerge; keep file and network access out of `@mcpdesc/core`.
 

diff --git a/package-lock.json b/package-lock.json