orchestrate/teamwork: conditional decomposition guidance (tracer bullets, expand-contract) v4.9.0

[sumitake]

Summary

Deferred follow-up B from #83 (companion to merged #84): orchestrate and teamwork gain conditional decomposition guidance for implementation work:

• Tracer-bullet vertical slices preferred when (and only when) a graph/milestone plan decomposes product-feature implementation: complete narrow path through every affected layer, demoable or independently verifiable, sized to one bounded worker invocation/session with explicit acceptance criteria (durable phrasing, not context-window-relative). Prefactoring first.
• Wide refactors are the exception, narrowly triggered: atomically codemoddable mechanical changes run as checkpointed, fully verified batches; expand–contract is reserved for migrations where old and new forms must genuinely coexist to keep callers and CI working — never merely because blast radius is large.
• Named inapplicability: research, operations, configuration, and decision-only graphs/milestones are explicitly out of scope for the guidance.
• Licensing: adapted portions attributed to mattpocock/skills to-tickets @2ab95809 (blob 96deac51, verified locally); full MIT notice in both specs; both members join MIXED_LICENSE_SKILL_MEMBERS (LicenseRef-PolyForm-Strict-1.0.0 AND MIT); provenance rows added. NOTICE unchanged (generalized in code-review: spec-fidelity + smell-baseline lenses (backward-compatible JSONL extension) v4.8.0 #84 by design).
• Version 4.8.0 → 4.9.0 across all seven surfaces; changelog fragment; marketplace regenerated.

Validation

• build_skills.py --check clean; check_release_consistency.py RESULT: OK; build-changelog.py --dry-run OK
• unittest discover -s scripts 319/319 OK; unittest discover -s tests 658/658 OK

Cross-check (verbatim)

Same consultation as #84 — Codex (gpt-5.6-sol, effort medium, direct codex exec under operator broker-bypass authorization) reviewed both follow-up plans in one round:

VERDICT: PROCEED-WITH-MODIFICATIONS

PR-B-relevant concerns integrated here: (6) expand–contract trigger narrowed to coexistence-required migrations, with checkpointed-batch alternative for codemoddable refactors; (7) "one context window" replaced with a durable bounded-invocation + acceptance-criteria bound; (5) full MIT notice carried in both touched specs with SPDX mixed-member classification.

author: claude
author_model: claude-fable-5 (effort: default)
standing_directives: skill-change workflow; #1 trigger phrases (descriptions unchanged — guidance is body-level); #3 release withheld per operator instruction 2026-08-03; #4 N/A (plugin change); #5 plugin README updated in this PR; #7 model+effort stated; #8 no fan-out
tier: 2
cross_check: PROCEED-WITH-MODIFICATIONS (codex gpt-5.6-sol, effort medium, direct codex exec under operator broker-bypass authorization 2026-08-03; raw verdict quoted in PR body; concerns 6+7 integrated here, 1-5 in #84)
post_condition: 319/319 + 658/658 tests OK; build --check clean; release-consistency OK; changelog dry-run OK; no coordinator/route change
mcp_coverage_gap: none — prose guidance only; gemini_mcp_path: retired / not applicable
contributor_rights: OPERATOR-CONFIRMED
operator_reserved: no
plugin_affected: this PR is the plugin change
readme_refresh_status: README updated (plugin repo); workspace companion at release (release currently withheld by operator)

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Keep atomically codemoddable changes atomic

When a mechanical interface or schema rename cannot leave any partial subset green—the exact case described here—splitting it into batches makes the first batch fail full verification, so the workflow cannot satisfy its acceptance check before proceeding. Apply an atomically codemoddable change as one atomic node and verify afterward; reserve independently verified batches for changes whose intermediate states remain valid. The same contradictory instruction should be corrected in teamwork and the generated skills regenerated.

AGENTS.md reference: AGENTS.md:L9-L10

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