Implementation entry for three Tier 2 ADRs (T2-A / T2-B / T2-C). All Stage 1 behaviors gated on user opt-in; default behavior unchanged from v0.12.0.

T2-A — project spec structure (templates/):
- templates/spec-template.md — CSI Three-Part Format (Part 1 General / Part 2 Behavior with explicit modal per clause + Acceptance criteria + Known implementations / Part 3 Verification) + Rejected alternatives + Amendment log + Closure ceremony block. Frontmatter carries id / status (draft|shared|published|archived) / modal default / supersedes / superseded-by / references.
- templates/spec-index-template.md — copy-and-fill scaffold for docs/specs/_index.md with sonmat opt-in flags (spec_awareness / spec_verification) and ≤50 line discipline.

T2-C — scribe spec amendment ritual (skills/scribe/SKILL.md):
- Novel Trap Recording extended with new step 5: when flavor=spec_gap AND project has docs/specs/_index.md declaring sonmat.spec_awareness: enabled AND gap maps to identifiable existing spec → propose successor spec generation (Yes / No log only / Edit first).
- Successor uses spec template, sets supersedes: original-id; original gets superseded-by: new-id back-reference.
- Closure ceremony auto-trigger when user accepts full supersession (status: archived) — sunset date and fork-prevention declaration required (PEP 404 model).
- LEARN journal entry written regardless of decision — captures deferred decisions as retrospective data (LPS 5-conversation model).

T2-B Stage 1 — hints.md Spec consumption sub-section:
- Auto-read docs/specs/_index.md at task start (only when sonmat.spec_awareness: enabled)
- Inline-reference relevant specs to user before acting on them (no silent assumption)
- Alerts only, no blocking — Stage 2 territory requires substrate baseline (separate ADR)
- Treat status: draft as non-binding
- Verify against spec body, not just index (index is hypothesis per scribe Bridge Note Authoring Principle 3)
- Stage 0 default behavior unchanged.

Refined via devil project-relevance gate before adoption: PPC-equivalent metric deferred to post-6mo retrospective; substrate baseline measurement gate prevents cargo-cult activation.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>