team-coordination

name	team-coordination
description	Coordinate agent teams for adversarial review (paired skeptic/verifier per facet, challenge round with disposition vocabulary, consolidated findings with confidence) or parallel implementation (task sizing 5-6 per teammate, non-overlapping files). Enforces independent analysis before shared conclusions. Reference only (`disable-model-invocation: true`); loaded only when `agentTeams: true` in settings.
allowed-tools	Bash, Read, TaskCreate, TaskList, TaskUpdate
agent	general-purpose
disable-model-invocation	true

Team Coordination

Domain skill for orchestrating agent teams. Only relevant when agentTeams: true in settings.

Requires: CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS environment variable.

Iron Law

INDEPENDENT ANALYSIS BEFORE SHARED CONCLUSIONS. Teammates who see each other's findings are contaminated reviewers.

The value of a team is independent perspectives. Sharing findings before independent analysis destroys that value.

When to Spawn Teams

Scenario	Recommendation	Rationale
Review with 3+ facets	Spawn team	Independent analysis enables adversarial protocol
Large feature (>5 acceptance criteria, independent modules)	Suggest team	Parallel implementation across modules
Debugging with competing hypotheses	Spawn team	Each teammate tests a different hypothesis
Small feature (<3 criteria)	Single session	Team overhead exceeds benefit
Sequential dependencies	Single session	Can't parallelize sequential work

Task Sizing

• 5-6 tasks per teammate — enough work to stay busy, not so much they lose focus
• Each task should be completable without coordination
• Tasks must have clear acceptance criteria
• Overlapping file sets → same teammate (avoid merge conflicts)

Adversarial Review Protocol

When spawning a review team, each facet runs as a paired reviewer (skeptic + verifier) with a disposition-only challenge round between them. The protocol is the contract frozen in .decisions/issue-86.md and emitted by commands/review.md Path A.

Cost expectation

Per /flow:review run with default 6-facet fan-out:

Phase	LLM calls
Phase 1 — Independent Analysis (5 agent facets × 2 + 2 holdout-validation Skill calls)	12
Phase 2 — Share findings (lead-only orchestration; no LLM call)	0
Phase 3 — Challenge (each Agent reviewer challenges the other's findings, 5 × 2; holdout-validation excluded — see review.md A.1 note)	10
Phase 4 — Synthesize (main agent, 1 consolidation pass)	1
Phase 5 — Emit consolidated output (lead-only; no LLM call)	0
Total	≈23 calls (≈3.8× single-session baseline of 6)

Wall-clock: ≈1.5–2× single-session via parallel dispatch within each phase. The cost is opt-in (agentTeams: false by default) and gated behind CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS.

Phase 1: Independent Analysis (paired reviewers per facet)

For each facet, dispatch two subagents with orthogonal prompt lenses. Both run in parallel and never see each other's findings during this phase.

Variant	System-prompt lens
skeptic	"Assume the diff is broken until proven otherwise. Flag every behavior you cannot prove correct from the code as written."
verifier	"Assume the diff is correct as a baseline. Look only for missed edge cases, undocumented contract assumptions, or invariants that aren't enforced."

Default 6-facet topology (12 invocations in one parallel dispatch — 5 Agent pairs and 2 Skill calls):

Agent(security-reviewer-skeptic) | Agent(security-reviewer-verifier)
Agent(code-reviewer-skeptic) | Agent(code-reviewer-verifier)
Agent(convention-checker-skeptic) | Agent(convention-checker-verifier)
Agent(test-runner-skeptic) | Agent(test-runner-verifier)
Agent(error-handler-inspector-skeptic) | Agent(error-handler-inspector-verifier)
Skill(holdout-validation) [skeptic lens] | Skill(holdout-validation) [verifier lens]

The holdout-validation pair is dispatched as Skills (not Agents) because the project does not define a holdout-validation agent — the skill IS the contract. The holdout-validation pair contributes findings to A.2 auto-consensus matching but is excluded from the Phase 3 challenge round by design, not because Skills lack a challenger prompt pattern.

The principled rationale: adversarial challenge (AGREE/DISAGREE/REFINE) exists for findings where reviewers can hold legitimately different subjective opinions about priority, severity, or category. Holdout findings are categorically different — they are objective claim-verification (file state vs self-reported claim). The file state is the arbiter, so DISAGREE is not a meaningful disposition. Including holdout in challenge would produce vacuous AGREE responses (re-check confirms what we already established) or confuse the protocol (DISAGREE based on what?). See commands/review.md A.1 for the full rationale.

Holdout findings carry their own confidence model: consensus when both lenses raised the same finding independently, unchallenged when only one lens raised it (signal: the lenses parsed the same claim differently or weighted scenario priority differently). They NEVER carry validated / refined / kept — those dispositions are challenge-round outputs.

Each returns P1/P2/P3 findings with file:line citations and a category. No challenge information is included in this phase — outputs are independent.

Phase 2: Share Findings

Lead collects all 12 finding sets (10 Agent + 2 Skill). No LLM call. Indexes findings by facet for the per-facet challenge round. Holdout-validation findings are indexed for A.2 auto-consensus matching only and bypass Phase 3.

Phase 3: Challenge (disposition-only, no diff re-read)

For each facet, dispatch each variant to challenge the OTHER variant's findings. The challenger does NOT re-read the diff. The challenger labels each of the other's findings with one of three dispositions:

Disposition	Meaning
AGREE	Challenger also flagged this OR confirms it as a real issue
DISAGREE	Challenger believes this is not a real issue (must give a one-line reason)
REFINE	Real issue, but priority/category differs (challenger states the corrected priority/category)

Challenge prompt (issued per facet, both directions in parallel):

You are reviewer-{A|B} for facet {facet}. Reviewer-{B|A} raised the following
findings on the same diff you reviewed independently. For each finding, respond
with exactly one line:

  {finding-id} AGREE
  {finding-id} DISAGREE: {one-line reason}
  {finding-id} REFINE: priority={P1|P2|P3} category={text}

Do NOT re-read the diff. Decide based on your prior independent analysis only.

Findings to challenge:
{list of the OTHER reviewer's findings: ID, file:line, priority, category}

10 challenge prompts run in parallel (5 agent facets × 2 directions; the holdout-validation Skill pair is excluded by design — see A.1 note for the principled rationale: holdout is objective claim-verification, not subjective judgment, so AGREE/DISAGREE/REFINE doesn't apply).

Phase 4: Synthesize (consolidation rules)

Lead applies the consolidation table to each finding:

Origin	Other reviewer's disposition	Consolidated confidence	Disposition vocab
Both raised independently (file ±2 lines, priority ±1)	n/a	HIGH	consensus
One raised, other AGREE	AGREE	HIGH	validated
One raised, other REFINE	REFINE	MEDIUM	refined (priority/category from REFINE)
One raised, other DISAGREE	DISAGREE	LOW	kept
One raised, other timed out / errored	none	MEDIUM	unchallenged
Both raised, both DISAGREE'd in challenge	n/a	DROPPED	excluded; logged in journal

Independence-match window (hard-coded for v1): same facet AND same file AND lines within ±2 AND priority within ±1 (P1↔P2 counts; P1↔P3 does not).

The disposition vocabulary consensus|validated|refined|kept|unchallenged is the controlled set emitted into the FLOW_REVIEW_CYCLE marker — see references/finding-ledger-parser.md for the marker schema.

Phase 5: Emit consolidated output

Lead writes the per-priority finding tables, folding confidence and disposition into the Finding cell as a trailing _(confidence · disposition)_ suffix:

### P1 — Critical
| Finding | Suggested Fix |
|---------|---------------|
| **F1 · security · `src/auth.ts:42`**<br>... _(HIGH · consensus)_ | ... |
| **F2 · correctness · `src/api.ts:88`**<br>... _(LOW · kept — B disagreed: "off-by-one is intentional")_ | ... |

And the extended FLOW_REVIEW_CYCLE marker (7 fields per row; example exercises three disposition values):

<!-- FLOW_REVIEW_CYCLE:{N} FINDINGS:[F1|P1|security|src/auth.ts:42|open|HIGH|validated,F2|P2|correctness|src/api.ts:88|open|MEDIUM|refined,F3|P1|race|src/job.ts:17|open|LOW|kept] -->

DROPPED findings do NOT appear in the marker; they are logged in the decision journal under ## Dropped after challenge for traceability.

Cognitive Bias Awareness

• Anchoring: A reviewer who reads another's findings before producing their own anchors on them. Phase 1 is strictly independent for this reason; the challenge round in Phase 3 explicitly forbids diff re-read so the reviewer cannot synthesize fresh "agreements" from re-reading.
• Groupthink: Confidence-HIGH-on-everything is a smell, not a goal. A healthy review surfaces some kept (challenged but disagreed) findings.
• Central-judge bias: The protocol intentionally has no third-agent challenger and no main-agent adjudicator. The lead consolidates mechanically via the table above; it does not opine on which finding is "really" correct.

Fallback Semantics (per-facet graceful degradation)

A failure in the paired/challenge mechanism never blocks /flow:review. Per-facet matrix:

Condition	Behavior
agentTeams: false	Skip paired protocol entirely. Emit Path A skipped: agentTeams=false. Using Path B (single-session). to stdout and use single-reviewer dispatch (the commands/review.md Path B fallback).
agentTeams: true AND env var CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS unset	Single-line WARN to stderr: agentTeams enabled but env var unset; using single-reviewer fallback. Use Path B.
agentTeams: true AND env var set, but one variant (skeptic OR verifier) fails to spawn for one facet	That facet uses single-reviewer fallback (the responding variant). Other facets continue paired. Note in output: facet {facet}: single-reviewer fallback (verifier failed to spawn).
Variant times out (timeouts.teammateTimeout)	Use the responding variant's findings only for that facet. Mark each finding as unchallenged (MEDIUM confidence).
BOTH variants fail for one facet	Re-dispatch with single-reviewer Path B for that facet. Note in output.
Challenge round itself fails (cannot dispatch challenger prompt)	Skip challenge step. Findings included as unchallenged. Do not block review.

Teammate Health Protocol

Timeout Handling

From settings: timeouts.teammateTimeout (default: 300 seconds)

If a teammate exceeds timeout:

1. Check if they have partial results
2. If yes, collect partial results and note as "incomplete review"
3. If no, mark the facet as "not reviewed" and proceed

Failure Handling

If a teammate crashes or returns an error:

1. Log the failure
2. Fall back to single-session review for that facet
3. Note in the review summary: "Facet X reviewed in single-session fallback"

Idle Handling

The nudge-idle-teammate.sh hook handles idle teammates:

• After 60s idle: "Check task list for unclaimed tasks"
• The hook sends feedback via stderr output (exits 0; exit code 2 has no defined semantics for TeammateIdle)

Implementation Team Protocol

When spawning an implementation team:

1. Lead creates task list with dependencies
2. Lead assigns task groups to teammates (non-overlapping file sets)
3. Each teammate:
   • Claims tasks from their group
   • Implements and commits
   • Marks tasks complete
4. Lead monitors via TaskList
5. Lead runs final verification after all teammates complete

Single-Session Fallback

When teams are disabled or spawn fails, all team patterns fall back to:

• Sequential Agent dispatch (parallel where independent)
• Main thread handles coordination
• No adversarial protocol (single perspective)

The calling command handles the fallback — this skill only provides team-specific knowledge.