# α close-out — cycle #400

**Author:** α (collapsed on δ)
**Date:** 2026-05-21
**Issue:** cnos#400 — Phase 5 of #366 (γ shrink)

## Summary

`gamma/SKILL.md` restructured from 748 → 499 lines (−33.3%). Coordination + closure + triage doctrine preserved and tightened; runtime-supervision mechanics cross-referenced to `harness/SKILL.md`, `release-effector/SKILL.md`, and `operator/SKILL.md`. The cnos#393 Implementation Contract block (7 axes + mesh + empirical anchor) kept verbatim per the issue non-goal. F1 (delta/SKILL.md stale Phase 4b forward-refs) and F2 (delta/SKILL.md frontmatter `requires.1` CUE type mismatch) absorbed from cnos#398's `cdd-iteration.md`.

## What landed

- `src/packages/cnos.cdd/skills/cdd/gamma/SKILL.md` — restructured (499 lines)
- `src/packages/cnos.cdd/skills/cdd/delta/SKILL.md` — F1 + F2 fixes (5 prose rewrites to past-tense Phase 4b/4c/5 narration; 1 frontmatter type fix)
- `.cdd/unreleased/400/` — gamma-scaffold.md, design-notes.md, self-coherence.md, beta-review.md, this file, beta-closeout.md, gamma-closeout.md, cdd-iteration.md

## Design decisions

1. **Kept Implementation Contract block verbatim** (cnos#393 non-goal). The 7 axes + mesh + cnos#389/#391/#392 empirical anchor are pinned doctrine; γ shrink does not touch them.
2. **Moved the polling shell mechanics out of γ** to a single-line cross-reference (`harness/SKILL.md §5.4`) plus the invariant statement "polling requires a query, a wake-up mechanism, and a reachability probe." The transition-loop bash already lived in harness §5.4 verbatim; γ-side was redundant.
3. **Compressed dispatch flow narration** from a 6-line pseudo-shell block to one inline cross-reference ("δ dispatches γ → α → β sequentially per `operator/SKILL.md` Algorithm + `harness/SKILL.md` §1").
4. **Compressed branch pre-flight bash** to the invariant rules; the mechanical sequence (`git fetch` + `rev-parse --verify` + `ls-tree` + `switch -c` + `push -u`) is referenced as "follows `CDD.md` §4.3 directly; γ does not restate them."
5. **Compressed the autonomous-coordinator decision-point table** by collapsing 7 identical "pause" rows into one row with "/-separated decision points → pause."
6. **Compressed katas** from full Scenario/Task/Expected/Common-failures formal blocks to compact single-paragraph form per kata. Preserved all required content (kata_surface: embedded stays valid).
7. **Added §3.9 Managerial-residue sweep as a binding rule** referencing `COHERENCE-CELL.md`. This makes the sweep a first-class γ obligation, not just a one-time pre-cycle exercise.
8. **F1 (delta stale refs)** — rewrote 5 prose locations from "Phase 4b pending" / "harness mechanics currently in operator" → past-tense "Phase 4b of cnos#366, landed at cnos#398" with explicit pointers to `harness/SKILL.md`. Also added a "Phase 5 — γ shrink (landed)" entry to delta §7 for future-cycle traceability.
9. **F2 (delta frontmatter)** — changed `requires.1` from YAML mapping (`- or: "..."`) to flat string (`- "or: ..."`). Disjunctive semantics preserved in plain prose; CUE schema (`requires?: [...string]`) satisfied. Minimum-invasive fix; broader frontmatter convention for disjunctive `requires` is out of scope (would be a CUE schema change).

## Open items / debt

None binding. The γ-side `## 3.9 Managerial-residue sweep` rule is new and may attract its own sweep over time as the protocol evolves.

## Implementation-contract conformance

| Axis | Pinned | Conformed |
|---|---|---|
| Language | Markdown | ✓ |
| CLI integration target | N/A | ✓ |
| Package scoping | `cnos.cdd/skills/cdd/{gamma,delta}/SKILL.md` | ✓ |
| Existing-binary disposition | restructured; mechanics cross-referenced; coordination + closure + triage stays | ✓ |
| Runtime dependencies | None | ✓ |
| JSON/wire contract | N/A | ✓ |
| Backward compat | All γ workflows continue; location of mechanics moves, not mechanics themselves | ✓ |
