Adverse — Multi-Agent Adversarial Code Review

This skill is the Claude Code-native side of the adverse project. The same logic is also available as a standalone CLI (adverse review …). When you run inside Claude Code, prefer this skill — it uses Claude Code's native Agent tool to spawn reviewers (no subprocess auth issues, faster) and calls Node helpers only for the deterministic source-collection and synthesis steps.

When to use this skill

The user explicitly asked for an adversarial / multi-perspective / panel review of their code, OR they're about to merge / land / ship a non-trivial change and asked for one more pass. If the diff is trivially mechanical (formatting, dependency bumps, typos), do NOT invoke this — say so and stop.

Prerequisites

node (>= 20) on PATH. Verify with node --version. The skill scripts live under ${SKILL_DIR}/scripts/ and are stdlib-only (no npm install needed).

If node is missing, tell the user: install Node 20+ from nodejs.org (or their package manager) and re-invoke. Do not fall back to a different implementation; the deterministic synthesizer is the contract.

Phase 0 — decide what to review

Pick scope before spending tokens:

1. If the user named a path, that's the scope.
2. Else if git status --porcelain reports uncommitted changes, review those

(diff mode against HEAD).

1. Else if the current branch is ahead of main (or master / the configured

upstream), review the diff since the merge base.

1. Else review the whole working directory.

State the scope you picked in one sentence so the user can redirect.

Phase 1 — collect source

Run the Node helper that walks the target and produces a single prompt-ready text block:

node ${SKILL_DIR}/scripts/collect.mjs --target <path> [--diff [base]] --out /tmp/adverse-source.txt --files-out /tmp/adverse-files.json

/tmp/adverse-source.txt is what you'll embed in the reviewer prompts. /tmp/adverse-files.json is the file list (use it to confirm scope to the user). The helper enforces the same source-size caps as the CLI.

If collect fails, surface the error to the user — it's almost always "target not found" or "diff is empty".

Phase 2 — round 1: independent reviews

Spawn three reviewers in parallel using Claude Code's Agent tool, one per persona. Each one gets:

• System prompt: read from ${SKILL_DIR}/scripts/prompts/<persona>.txt

(auditor / adversary / pragmatist).

• User message: the contents of /tmp/adverse-source.txt prefixed by

${SKILL_DIR}/scripts/prompts/round1.txt.

• Model: opus unless the user asked for a different one. If the user

picks a smaller model, pass it to all three personas — different models across personas defeats the single-model design.

Each subagent must respond with a single JSON object matching this schema:

{
  "persona": "<auditor|adversary|pragmatist>",
  "verdict": "approve|conditional|reject",
  "summary": "<one sentence>",
  "findings": [
    {
      "severity": "critical|warning|info",
      "file": "<path or null>",
      "line": <int or null>,
      "title": "<short noun phrase>",
      "detail": "<2-6 sentences>",
      "fix": "<concrete remediation or null>"
    }
  ]
}

Save each parsed JSON object to disk:

• /tmp/adverse-round1-auditor.json
• /tmp/adverse-round1-adversary.json
• /tmp/adverse-round1-pragmatist.json

If a subagent returns malformed JSON, retry that one persona once with the parser/validator error appended to the original prompt. If the retry also fails, drop that persona. If fewer than 2 personas survive, abort the run and report the failure — synthesis requires at least 2 voices.

When all three are done, combine them into one file for the next phase:

node ${SKILL_DIR}/scripts/combine.mjs \
    --round1 /tmp/adverse-round1-auditor.json /tmp/adverse-round1-adversary.json /tmp/adverse-round1-pragmatist.json \
    --out /tmp/adverse-round1.json

Phase 3 — round 2: cross-review

For each persona that produced a valid round-1 review, spawn a subagent that:

• Sees ALL round-1 reviews (the combined /tmp/adverse-round1.json).
• Validates findings it agrees with (cross-lane validation is the signal).
• Challenges findings it thinks are wrong / overstated (with a concrete

reason).

• Optionally adds new findings the other angles surfaced.

System prompt: same persona file as round 1. User prompt: the contents of ${SKILL_DIR}/scripts/prompts/round2.txt, then the round-1 combined JSON, then the source block.

Output schema:

{
  "persona": "<auditor|adversary|pragmatist>",
  "validate":  [{ "from": "<reporter>", "title": "<title>", "reason": "<…>" }],
  "challenge": [{ "from": "<reporter>", "title": "<title>", "reason": "<…>" }],
  "added":     [<finding object>]
}

Save each to /tmp/adverse-round2-<persona>.json and combine:

node ${SKILL_DIR}/scripts/combine.mjs \
    --round2 /tmp/adverse-round2-*.json \
    --out /tmp/adverse-round2.json

If the user asked for a faster review or --single-round, skip phase 3 entirely. The synthesizer treats missing round 2 as an empty cross-review.

Phase 4 — synthesize

Run the deterministic synthesizer. This produces the canonical report — never LLM-render the findings yourself, the synthesizer's groupings (cross-validated / consensus / disputed / solo) carry the signal.

node ${SKILL_DIR}/scripts/synthesize.mjs \
    --round1 /tmp/adverse-round1.json \
    --round2 /tmp/adverse-round2.json \
    --out /tmp/adverse-report.md \
    --json-out /tmp/adverse-report.json \
    --html-out /tmp/adverse-report.html

Read /tmp/adverse-report.md and present a summary to the user, not the full report:

1. The verdict line (e.g., SHIP-WITH-CAVEATS (2/3 ship, 1/3 block)).
2. Counts by severity and confidence.
3. The top 3 findings (cross-validated first, then consensus, then disputed)

with one-line previews.

1. A pointer to the full report on disk and the HTML dashboard.

Then ask the user how they want to proceed:

• Apply fixes for cross-validated findings only? (highest confidence)
• Apply fixes for everything except disputed? (most common)
• Show me a specific finding's full reasoning?
• Just save the report; I'll review it myself.

Do not start editing files until the user picks one.

Phase 5 — clean up

After the user is done with the report, delete /tmp/adverse-* and tell the user the run is complete. Do not commit those files.

Failure handling

Notes for the orchestrator

• This skill spends ~6 model calls (3 × round-1 + 3 × round-2). Skip round 2

on user request to halve it.

• Persona prompts are deliberately written to "stay in your lane" — do NOT

override them with general-purpose review instructions, doing so collapses the orthogonality the design relies on.

• The synthesizer is deterministic Python-free Node code (synthesize.mjs).

Counting validate/challenge edges is the consensus signal; do not run a fourth LLM "judge" pass.

• The standalone CLI (adverse review) is an alternative path that

subprocesses any coding agent (claude -p, codex exec, …). Mention it to the user only if they ask how to run this without Claude Code.