adversarial-review

v0.7.0 — Cross-host adversarial review for coding workflows. Works in Claude Code, Codex, Pi, and Grok from the same source: detects which agent host you're running in and routes the heavy critique to the OTHER agent.

Critique discipline (v0.7): break confidence rather than validate; expensive attack surfaces first; material-only findings; steerable focus; terse ship/no-ship summary. Lessons adapted from OpenAI Codex Companion — see references/codex-lessons.md.

The principle

The partner reviews, never the host.

Two models examining the same artifact from different angles catch more issues than either alone. Each has different training biases, blind spots, and reasoning patterns. Disagreements between the two surface the highest-value findings - the ones a single reviewer would miss.

This plugin enforces that principle automatically:

• Running in Claude Code -> external reviewer is Codex (codex exec, gpt-5.6-sol xhigh via ChatGPT subscription auth)
• Running in Codex -> external reviewer is Pi xAI OAuth Grok 4.5 with xhigh thinking first, then Claude (Opus, xhigh) via claude -p, then Grok Build CLI with grok-4.5 --reasoning-effort xhigh
• Running in Claude Code fallback order after Codex is Grok Build CLI, then Pi model chain (xai-oauth/grok-4.5 with --thinking xhigh, opencode-go/glm-5.2:high, moonshotai/kimi-k2.7-code-highspeed direct API), then Gemini via non-interactive Antigravity CLI (agy --print)
• Everything unavailable -> degraded mode with explicit banner: the host reviews itself, but the user is told the cross-host principle was bypassed

How it works

SKILL.md (same file in both hosts)
   │
   ├─ host runs lib/call-external.sh
   │     │
   │     ├─ lib/detect-host.sh  (override -> env -> PPID walk)
   │     ├─ partner = NOT host
   │     ├─ ADVERSARIAL_REVIEW_DEPTH = 1  (anti-recursion guard)
   │     ├─ try partner (codex exec OR claude -p)
   │     ├─ on fail -> grok, then pi/opencode-go
   │     ├─ on fail -> Gemini via Antigravity
   │     └─ on fail -> degraded mode (exit 2)
   │
   ├─ host runs its own independent analysis (no peeking at partner output)
   ├─ cross-validate: tag findings [cross-validated] / [external-only] / [host-only]
   └─ return unified output (P0-P3 severity, evidence, recommendation, partner-attribution)

No haiku courier subagent (removed in 0.5.0 - added complexity without value). The main session does the dispatch and synthesis directly.

Skills

Skill	What it does
/adversarial-review:adversarial-review	Single entry point. Classifies input (plan, code, prompt) and runs the matching procedure: plan critique with revised plan, red-team code review with patch, or prompt-engineering analysis (host-side, no external).

In Codex, after running the install script, the same skills are available as $<skill-name> (Codex prompt-prefix convention).

Install

Claude Code

# Add the marketplace and install the plugin
claude plugin marketplace add ~/repos/skills/plugins/adversarial-review
claude plugin install adversarial-review@adversarial-review

# Reload in current session
/reload-plugins

Codex (additionally)

# Symlinks each skills/<name>/ into ~/.codex/skills/
bash ~/repos/skills/plugins/adversarial-review/adapters/codex-skill/install.sh

Verify both:

claude plugin list                 # should show adversarial-review enabled
ls -la ~/.codex/skills/            # should show the adversarial-review symlink back to this repo

Prerequisites

At least one external partner CLI must be authenticated for cross-host review to work (otherwise you'll get DEGRADED mode):

# When host=claude, partner=codex:
codex login

# When host=codex, partner=Pi xAI OAuth Grok 4.5 with xhigh thinking first:
pi --version

# Host=codex fallback after Pi:
claude  # interactive once to register OAuth, then `claude -p` works headless

# Optional fallback:
grok --version
agy --version  # Antigravity CLI, authenticated through the Antigravity app

For ChatGPT-account Codex users, also add to ~/.codex/config.toml:

forced_login_method = "chatgpt"

(Without this, codex exec returns 404 "Model not found" even though the TUI works. See references/codex-integration.md for the gotcha details.)

Verify

# Detection in Claude Code
bash ~/repos/skills/plugins/adversarial-review/lib/detect-host.sh
# -> claude

# Detection inside Codex
codex exec --sandbox read-only --skip-git-repo-check \
  "bash $HOME/repos/skills/plugins/adversarial-review/lib/detect-host.sh"
# -> codex

# Override
ADVERSARIAL_REVIEW_HOST=codex bash lib/detect-host.sh
# -> codex

# Degraded mode (non-destructive smoke)
echo "test" | ADVERSARIAL_REVIEW_FORCE_DEGRADED=1 \
  bash lib/call-external.sh
# -> exit 2, stdout begins with "⚠️  DEGRADED MODE"

# Anti-recursion
echo "test" | ADVERSARIAL_REVIEW_DEPTH=1 \
  bash lib/call-external.sh
# -> exit 1, stderr "recursion detected"

Use

# In Claude Code
/adversarial-review:adversarial-review                 # paste anything - plan, code, diff, prompt, or "review uncommitted"

# In Codex (after running adapters/codex-skill/install.sh)
$adversarial-review please review the plan I'm about to implement: ...
$adversarial-review review my changes: ...

Architecture diagram

Open in Excalidraw

See also

• references/codex-lessons.md - stance/attack-surface/finding-bar adopted from Codex Companion
• references/output-standards.md - P0-P3, material bar, header/summary contract
• PLANS.md - upgrade plan + future pi-companion plan
• references/host-detection.md - the override -> env -> PPID walk priority
• references/codex-integration.md - Codex CLI specifics + forced_login_method gotcha
• references/claude-integration.md - claude -p --model opus --effort xhigh
• references/pi-integration.md - Pi model chain
• references/antigravity-integration.md - Gemini through non-interactive Antigravity CLI
• references/fallback-chain.md - external chain + Antigravity + degraded path
• AGENTS.md - agent-side rules (severity, honesty, anti-recursion contract)
• CLAUDE.md - Claude Code dev workflow

License

MIT