Flow Execution (Single-Chapter Subagent Pipeline, Pre-Review Sync, & Public-Seam TDD)

Trigger

Use for implement (../flow/references/implement.md) and status (../flow/references/status.md).

contract: worksheet-execution-v1
invariants:
  - one-chapter-per-implement-run
  - worksheet-first-bounded-read-set
  - execution-preflight
  - public-seam-tdd-no-mocked-sut
  - fail-closed-no-production-mutation
  - atomic-task-commit
  - pre-review-present-tense-markdown-sync
  - chapter-code-and-doc-review-before-stop
authority: skills/flow/references/implement.md

Workflow

1. Active Chapter Resolution & Execution Preflight (/flow:status or /flow:implement):
   • Read root .agents/bundles/specs/<flow_id>/spec.md, chapters/index.md (when has_chapters: true), and only the active current_chapter's spec.md + tasks/*.md (../flow/references/state.md).
   • Verify depends_on_chapters are completed with non-null last_reviewed_commit and planning_status == "complete"; if planning_status == "empirical_dependent", stop cleanly with zero production edits and route to /flow:revise <flow_id> <chapter_id>.
   • Run the task preflight (dependencies_closed, worksheet_complete, verification_strategy_declared, plan_identity_matches, target_symbols_exist). On mismatch, mark the task state: blocked ([!]) with zero production edits and route to /flow:revise.
2. Isolated Subagent Task Pipeline (1–4 Tasks in Active Chapter Only):
   • Execute strictly one chapter (1–4 tasks) per /flow:implement run, dispatching one fresh isolated @executor subagent per task worksheet (model: inherit; run_workflow pipeline() with type_name="self" and agents/executor.md on Google Antigravity).
   • Each @executor stays inside its worksheet's Bounded Read Manifest (read_set <= 6 files), collects initial evidence (behavior_tdd / regression_tdd Red first), implements through the real System Under Test (applying the Hypothesis-Driven Bug Diagnosis Loop on non-obvious failures), verifies Green + fast lint (exit 0), and atomically commits its owned files plus synced task state/commit and [x] [<sha>] checklist marker.
3. Chapter Closeout Sequence (Checkpoint → Present-Tense Sync → Zero-Context Review → Hard Stop):
   • Chapter Recovery Checkpoint: Run the chapter's aggregate lint and test suite (exit 0).
   • Present-Tense Markdown, OKF, & Full-Plan Sync: Dispatch an isolated sync subagent (type_name="self" on Antigravity) to update affected .agents/bundles/knowledge/** and user docs/** in present tense, rewrite chapters/<ch_id>/spec.md, chapters/index.md, and root specs/<flow_id>/spec.md ([k/N files documented] and ## 6. Current State & Remaining Plan Snapshot) in place with zero chronological history (logging only in .agents/bundles/log.md), and commit the synced docs.
   • Zero-Context Chapter Code & Markdown-Sync Review: Dispatch isolated @code-reviewer + @quality-reviewer (type_name="self" on Antigravity) across chapter_base_commit..HEAD covering both code/tests and synced Markdown/OKF files; remediate any ADOPT findings and re-verify.
   • Review Stamp, Pointer Advance, & Hard Stop: Stamp last_reviewed_commit: <REVIEWED_HEAD_SHA> and state: completed in chapters/<ch_id>/spec.md, mark - [x] [<REVIEWED_HEAD_SHA>] <ch_id> and advance current_chapter + last_reviewed_chapter + last_reviewed_commit in root specs/<flow_id>/spec.md, commit closeout metadata, and stop cleanly at the chapter boundary (recommending /compact or a fresh session before the next chapter).

Guardrails

• Execute one task worksheet per subagent turn and at most one chapter (1–4 tasks) per /flow:implement invocation; never chain multiple chapters in one session turn.
• Always run present-tense Markdown/OKF sync before Zero-Context Chapter Review so reviewers verify both code and living docs, and stamp last_reviewed_commit before stopping so cross-harness Stop hooks pass cleanly.
• Never mark a task or chapter completed without fresh exit 0 verification, and never create/mutate Git tags or push without explicit user instruction.

Output

Return the completed chapter/task summary, verification exit codes, atomic task and sync commit SHAs, Chapter Review Adjudication summary, last_reviewed_commit, remaining chapters from the full plan, and /compact + next /flow:implement <flow_id> (or /flow:finish <flow_id>) handoff.

Validation

Confirm all chapter verification commands exited 0, every tasks/<id>-<slug>.md state/commit matches its spec.md checklist, root spec.md + chapters/index.md + knowledge/** + docs/** are synced in present tense without historical prose, and last_reviewed_commit covers every completed task commit in the chapter.