Codex FIX7 Blueprint Recheck 5 - Readme First

Date: 2026-06-09 Mode: READ-ONLY production; KB review/checkpoint writes only.

Final status: FIX7_REFACTOR_BLUEPRINT_CODEX_RECHECK_5_NEEDS_T1_FIX

T1 correctly introduced a staged approval-envelope model and rebound the affected guards/packages. Codex cannot seal it yet because the hash contract is not byte-complete and the proposed anchor is not proven immutable.

Remaining blocker classes:

1. Canonical digest definitions are incomplete and envelope_manifest_sha256 does not bind every authority-bearing envelope field.
2. full_document_sha256 for self-host doc 00 is circular/inconsistent with the EXCLUDE rule; checkpoint self-host claims are inconsistent with the actual corpus/markers.
3. The Codex checkpoint is called immutable but no exact immutable revision/hash/signature/append-only anchor mechanism is defined.

No production implementation, Stage 2.6B, permit, REAL_RUN, QT001 apply, activation, repoint, or owner/ACL cutover is authorized.