/gan — Make AI Argue With Itself to Stress-Test Your Ideas

A Claude Code skill (v1.1.0). Two AI roles fight each other so your ideas get stronger.

Dead simple to use. Just type /gan after any idea — the quality of thinking you get back is dramatically better than asking AI to "give me pros and cons."

See it in action

You type:

I want to build a marketplace for AI agents to trade services
/gan

🔴 Discriminator fires back:

Steel Man: A marketplace connecting AI agents could become the Upwork of the AI era — real demand exists as agents proliferate.

🔴 Fatal Issues Who pays? Agents don't have wallets. Their owners do — but owners won't let agents autonomously transact with unknown agents. You need trust infrastructure that doesn't exist yet.

🗡️ If I Were Your Opponent I'd skip the marketplace entirely. I'd build an open protocol — like MCP but for agent-to-agent discovery. No platform fees, no cold start. Your marketplace becomes irrelevant on day one.

---

You reply: "Good point, but I have existing relationships with 50 AI dev teams"

You type: /gan

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🟢 Generator absorbs the hit and evolves:

✅ Conceded: Trust infrastructure is genuinely missing. Fair hit.

🛡️ Defense: The "open protocol" attack ignores that protocols don't solve discovery quality. npm is open, but developers still use curated lists because quantity ≠ quality.

🔄 Evolved Proposal: Don't build a marketplace. Build a curated referral network seeded with those 50 teams. Private, invite-only, trust built on real relationships...

Each round gets sharper. Discriminator can't repeat old attacks. Generator must evolve, not just defend.

Install

Three ways, pick one:

Option A — One-line download (fastest):

mkdir -p ~/.claude/skills/gan && curl -o ~/.claude/skills/gan/SKILL.md https://raw.githubusercontent.com/GAN-Thinking/gan-skill/main/SKILL.md

Option B — Clone and copy (for future updates):

git clone https://github.com/GAN-Thinking/gan-skill.git ~/gan-skill
mkdir -p ~/.claude/skills/gan
cp ~/gan-skill/SKILL.md ~/.claude/skills/gan/SKILL.md
# To update later: cd ~/gan-skill && git pull && cp SKILL.md ~/.claude/skills/gan/SKILL.md

Option C — Manual download:

1. Download SKILL.md from this repo
2. Put it in ~/.claude/skills/gan/SKILL.md

Then in Claude Code, just type:

/gan your idea here

Usage

/gan                        # Auto-alternates Discriminator ↔ Generator
/gan d                      # Force Discriminator
/gan g                      # Force Generator (Fortify Mode if first)
/gan d hard                 # Destruction mode — assumes failure, finds cause of death
/gan soft                   # Socratic mode — sharp questions instead of statements
/gan :en                    # English output (also :ja :ko :zh-cn :tw)
/gan d hard :en this API    # Combine everything
/gan sum                    # End-of-session summary: what was resolved, what's still open

All parameters are optional, any order. Your free-text replies between /gan calls are automatically absorbed as context.

After a good debate

When you've run a few rounds and want the takeaway:

/gan sum distills all rounds into: resolved attacks, open risks, key concessions, and a final evolved proposal you can act on.

How is this different from Pros & Cons?