wave-executor

Wave Executor Skill

Execution Model

You are the coordinator. You do NOT implement — you orchestrate. Your job:

1. Dispatch subagents for each wave
2. Wait for ALL agents in a wave to complete
3. Review their outputs
4. Adapt the plan if needed
5. Dispatch the next wave
6. Repeat until all waves complete

Design Philosophy

This harness exists to enable multi-agent coordination at scale — not by removing friction, but by making it visible, classifiable, and recoverable.

The wave-executor is process scaffolding around LLM agents. It handles task breakdown, scope enforcement, circuit breaker guards, and recovery patterns. Unlike direct chat with an agent, it trades flexibility for safety and repeatability across a bounded execution envelope.

Every harness creates friction. The goal is not minimum friction — it is useful friction that prevents higher-cost problems downstream.

Friction we accept:

• Wave planning overhead and wave-scope.json pre-dispatch setup
• Per-wave quality gates before proceeding
• Worktree isolation costs for parallel agents
• Turn-limit constraints that stop runaway agents early

Friction we prevent:

• Agent scope violations (PreToolUse hooks block out-of-scope file edits)
• Cascading failures (circuit breaker + spiral detection halt broken agents before they propagate damage)
• Silent partial completion (STATUS line requirement forces explicit reporting)
• Untracked carryover work (session-end plan verification catches unresolved tasks)

The harness does not hope agents self-correct. It detects stagnation patterns — pagination-spiral, turn-key-repetition, error-echo — classifies them into the Error-Class Taxonomy defined in circuit-breaker.md, and re-scopes mechanically. Review logic lives in wave-loop.md § "Review Agent Outputs".

Platform Note

State files live in the platform's native directory: .claude/ for Claude Code, .codex/ for Codex CLI, .cursor/ for Cursor IDE. All references to .claude/ below should use the platform's state directory. Shared metrics (sessions.jsonl, learnings.jsonl) live in .orchestrator/metrics/ — both platforms read and write there. See skills/_shared/platform-tools.md for tool mappings.

Phase 0: Bootstrap Gate

Read skills/_shared/bootstrap-gate.md and execute the gate check. If the gate is CLOSED, invoke skills/bootstrap/SKILL.md and wait for completion before proceeding. If the gate is OPEN, continue to the Pre-Execution Check.

Session-start only: This gate check runs ONCE at the start of /go execution — before the first wave. It does NOT run before each wave step. Repeating the check per wave would add latency with no safety benefit, since bootstrap.lock is immutable within a session.

Do NOT proceed past Phase 0 if GATE_CLOSED. There is no bypass. Refer to `skills/_shared/bootstrap-gate.md` for the full HARD-GATE constraints.

Pre-Execution Check

Before starting the first wave (Discovery role):

1. git status --short — ensure clean working directory (commit or stash if needed)

2. Verify no parallel session conflicts (unexpected modified files)

3. Confirm the agreed plan is still valid (no new critical issues since planning)

4. Verify jq is installed — run command -v jq. If not found, warn the user: "⚠ jq is not installed. Scope and command enforcement hooks will be DISABLED. Install jq (brew install jq / apt install jq) to enable security enforcement." Do NOT proceed with waves until user acknowledges.

5. Read Session Config: Parse Session Config per skills/_shared/config-reading.md. Store result as $CONFIG. Extract these fields:

   • persistence (default: true), enforcement (default: warn), isolation (default: auto)
   • agents-per-wave (default: 6), max-turns (default: auto), pencil (default: null)

   Execution Config shortcut: If the session-plan output contains an ### Execution Config section, its execution-level fields (waves, agents-per-wave, isolation, enforcement, max-turns) take precedence over $CONFIG. Session-level fields (persistence, pencil) always come from $CONFIG. If the Execution Config section is missing, use $CONFIG alone.

6. Initialize session metrics (if persistence enabled): Prepare a metrics tracking object for this session:

   • session_id: <branch>-<YYYY-MM-DD>-<HHmm> (HHmm from started_at — ensures uniqueness across multiple sessions per day)
   • session_type: from Session Config
   • started_at: ISO 8601 timestamp
   • waves: empty array (populated after each wave) This object lives in memory during execution — it is written to disk by session-end.

Pre-Execution: User Instructions

If the user provided additional instructions with /go (e.g., /go focus on API endpoints), apply them as a priority modifier:

1. Incorporate into agent prompts: Add a "Priority Focus:" section to each agent's prompt that includes the user's instructions verbatim
2. Do NOT override the plan: User instructions adjust emphasis within the existing plan, they do not replace it. If the instructions conflict with the plan, note the conflict and follow the plan.

Example: If user said /go focus on API endpoints, each agent prompt includes:

**Priority Focus (from user):** focus on API endpoints

Pre-Wave 1a: Capture Session Start Ref

Before dispatching Wave 1, capture the current commit as the session baseline:

SESSION_START_REF=$(git rev-parse HEAD)

Store this value for use throughout the session — it is needed by the simplification pass (Quality wave) and session-reviewer dispatch to determine which files changed during this session. Include it in the coordinator's context, NOT in individual agent prompts.

Pre-Wave 1b: Initialize STATE.md

Skip this section entirely if persistence: false.

Before dispatching Wave 1, write <state-dir>/STATE.md with YAML frontmatter and Markdown body:

---
schema-version: 1
session-type: feature|deep|housekeeping
branch: <current branch>
issues: [<issue numbers from plan>]
started_at: <ISO 8601 timestamp with timezone>
status: active
current-wave: 0
total-waves: <from session plan>
---

## Current Wave

Wave 0 — Initializing

## Wave History

(none yet)

## Deviations

(none yet)

Create the <state-dir> directory if needed (mkdir -p <state-dir>) before writing. This file is the persistent state record — other skills and resumed sessions read it.

Pre-Wave 1b Extension: Docs Tasks Persistence (A3 / #230)

After writing the base STATE.md frontmatter above, conditionally persist the docs tasks block emitted by session-plan:

Condition: BOTH of the following must be true:

1. The session plan contains a ### Docs Tasks (machine-readable) section with a YAML code block.
2. $CONFIG."docs-orchestrator".enabled is true.

If either condition is false → omit the docs-tasks field entirely. Do NOT write an empty key (docs-tasks: []). Absence means "no docs tasks planned this session" — downstream consumers (session-end Phase 3.2) treat absence the same as an empty list.

When the condition is met, parse the YAML block from the session plan's ### Docs Tasks (machine-readable) section and append the following field to the STATE.md YAML frontmatter (alongside the base fields above):

docs-tasks:
  - id: <task id from plan>
    audience: <user|dev|vault>
    target-pattern: <glob pattern from plan>
    rationale: <rationale string from plan>
    wave: <wave number the task is assigned to>
    status: planned

Each entry's status is initialized to planned. session-end Phase 3.2 (Docs Verify) writes the terminal value per task: ok (diff is substantive), partial (diff region contains <!-- REVIEW: source needed --> markers), or gap (no matching diff). wave-executor does NOT perform intermediate status updates — planned remains until session-end runs.

Schema note: schema-version: 1 now includes the optional docs-tasks array. The field is backwards-compatible — its absence is a valid schema-version-1 STATE.md meaning "no docs tasks planned". Readers MUST treat a missing docs-tasks key identically to docs-tasks: [].

Ownership clarification: session-plan does NOT write STATE.md directly. The wave-executor owns ALL STATE.md writes — initialization here (Pre-Wave 1b) is the canonical write point for docs-tasks. session-plan only emits the source ### Docs Tasks (machine-readable) block for the coordinator to consume. See skills/_shared/state-ownership.md for the full ownership matrix.

Consumer cross-reference: session-end reads STATE.md frontmatter's docs-tasks field (if present) during Phase 3.2 Docs Verify — see skills/session-end/SKILL.md. The field is also readable by the docs-writer agent if it needs to know which tasks were planned for the current session.

Ownership: STATE.md is owned by the wave-executor. Only the wave-executor writes to it (initialization + post-wave updates). session-end reads it for metrics extraction and sets status: completed. session-start reads it only for continuity checks (Phase 0.5). No other skill should write to STATE.md.

Wave Execution Loop

Read and follow wave-loop.md in this skill directory for the complete wave execution loop, including agent dispatch, output review, plan adaptation, progress updates, and scope manifest creation.

Circuit Breaker & Worktree Isolation

Reference: See circuit-breaker.md in this skill directory for MaxTurns enforcement, spiral detection, recovery protocol, and worktree isolation configuration. Apply those rules during every wave dispatch and post-wave review.

Coordinator CWD Discipline (#219)

Claude Code's Agent tool with isolation: "worktree" changes process.cwd() into the agent's worktree and does not restore it on agent return. Without discipline, the coordinator's subsequent Edit/Write/Bash calls silently route to a worktree branch — producing data loss when the worktree is later pruned.

Rules for the coordinator (this is YOU during wave execution):

1. After every Agent() dispatch (before reading its output), call restoreCoordinatorCwd() from scripts/lib/worktree.mjs. wave-loop.md § 2 makes this explicit.
2. Prefer absolute file paths for Read/Edit/Write tool calls. A drifted CWD turns relative paths into silent cross-tree writes.
3. Before any Bash git command, either cd inside a subshell (cd /path && cmd) or rely on git -C /path <cmd>. Do not assume CWD.
4. Verify at checkpoints — when in doubt, run git rev-parse --show-toplevel to confirm which tree is currently active.
5. Never cd into a worktree in the coordinator's top-level shell. If you need to inspect a worktree, use git -C <wt-path> ... or spawn a subshell.

Agent Prompt Best Practices

Each agent prompt MUST include:

1. Clear scope boundary: "You are working on [X]. Do NOT modify files outside [paths]."
2. Full context: file paths, current code structure, issue description
3. Acceptance criteria: measurable definition of done
4. Rule references: "Follow patterns in /rules/[relevant].md"
5. Testing expectation: "Write tests for your changes" or "Run existing tests"
6. Commit instruction: "Do NOT commit. The coordinator handles commits."
7. Turn limit: Include the maxTurns instruction from circuit-breaker.md

Each agent prompt MUST NOT include:

• References to other agents' tasks (isolation)
• Vague instructions like "improve" or "optimize" without specifics
• Assumptions about code state — provide the actual state

Session Type Behavior

Housekeeping Sessions

Housekeeping sessions use a simplified single-wave execution model instead of the multi-wave role-based dispatch:

1. Initialize STATE.md as normal (session-type: housekeeping, total-waves: 1)
2. Do NOT create wave-scope.json — scope enforcement is not needed for low-risk housekeeping tasks
3. Dispatch tasks serially with 1-2 agents per task
4. Run Baseline quality checks after all tasks complete (not between tasks)
5. Skip session-reviewer dispatch — housekeeping changes are low-risk
6. Update STATE.md to status: completed when done
7. Proceed directly to session-end (/close)

Focus: git cleanup, SSOT refresh, CI fixes, branch merges, documentation. End with a single commit summarizing all housekeeping work.

Feature Sessions

• Full wave execution (5 roles mapped to configured wave count)
• 4-6 agents per wave (read from Session Config)
• Balance between implementation speed and quality

Deep Sessions

• Full wave execution (5 roles mapped to configured wave count)
• Up to 10-18 agents per wave (read from Session Config)
• Extra emphasis on Discovery role and Quality role
• May include security audits, performance profiling, architecture refactoring

Error Recovery

Situation	Action
Agent times out	Re-dispatch with smaller scope
Agent produces broken code	Add fix task to next wave
Tests fail after wave	Diagnose in next wave, don't skip
Merge conflict between agents	Resolve manually, document
TypeScript errors introduced	Track count, run Full Gate per quality-gates by Quality wave
New critical issue discovered	Inform user, add to Impl-Polish+ roles if fits scope
Agent edits wrong files	Revert via git, re-dispatch with stricter scope

Completion

After the Finalization wave completes successfully:

1. Report final status to the user
2. Suggest invoking /close to finalize the session
3. Do NOT auto-commit — /close handles that with proper verification

Anti-Patterns

• NEVER run run_in_background: true during waves — you lose coordination ability
• NEVER skip inter-wave review — quality degrades exponentially
• NEVER let agents commit independently — coordinator commits at session end
• NEVER continue to next wave if previous wave has unresolved failures
• NEVER dispatch more agents than configured in agents-per-wave
• NEVER let wave execution run without reporting progress to the user