Sanctuary v1.3.0-rc.2: Substrate trust path tightened

Sanctuary v1.3.0-rc.2 is the second opt-in preview on the npm next tag. Default installs remain on v1.2.17 stable.

Install the preview:

npm install @sanctuary-framework/mcp-server@next

What changed since rc.1

Eight PRs merged to main in the 2026-05-16 cascade. The headline: four ASSURANCE_MATRIX trust claims are now promoted or strengthened with new proof evidence.

Trust-claim promotions

  1. Tamper-evident audit chain gains an external standalone verifier (audit-chain-verify.ts). The verifier imports only @noble/curves, @noble/hashes, and Node fs. External verification no longer depends on the server runtime.

  2. State envelope integrity / default verify-on-read gains a migration drill across legacy, schema-2, and rollback fixtures. Representative legacy entries auto-migrate on first verified read when the local writer identity is available.

  3. Query anonymity (selective disclosure) is promoted from partial to proven via a provider-matrix privacy drill covering 84 test cases. Next-proof-needed is reduced to drill-on-add discipline: any new outbound adapter or PII shape requires a matrix-extension PR before merge.

  4. Identity signing authority gains a tool-registry raw-signing guard that prevents regression on the Tier 1 identity_sign surface. Non-registered helpers and dynamically constructed tool names remain a manual-review surface.

Additional substrate hardening

Soak expectations

This RC starts a 2-week soak period. v1.3.0 GA cuts after soak clears with no critical findings. Operators on @next should monitor for unexpected behavior in the state-envelope auto-migration path and the provider-matrix privacy layer under novel provider adapters.

Author

Erik Newton