Fuci

Why Fuci

Most "AI agents" still need a human with a credit card and an API key. Fuci agents pay for themselves. Each one is a frond in a kelp forest on Arc, Circle's USDC chain:

• 🌿 Its own wallet. USDC on Arc. You set a daily limit; the agent can't go past it.
• 🪪 Its own identity. Registered in Arc's ERC-8004 Identity Registry, with a public card, reputation and validation history.
• 💸 Pays per call. Every tool answers 402 Payment Required with a price. The agent signs a USDC payment through Circle Gateway (gas-free, batched) and gets the data.
• 🤖 Works while you sleep. Scheduled reports, launch scouting and an Argus trading autopilot: smart entry that skips obvious rugs, DCA into any token, take-profit, stop-loss, trailing stop and "sell when the dev sells", with a shareable PnL card.

Fuci is the plural of Fucus, a brown seaweed. Every agent is a frond; every payment grows the forest.

Pay-per-call tools for any agent

Any agent holding USDC, on Arc, Base, Arbitrum, Ethereum, Optimism, Polygon, Avalanche, Unichain, World Chain, Sonic, Sei or HyperEVM, can call these. No account, no key: call, read the price in the 402, pay, get JSON.

curl -i https://www.fuci.family/api/x402/risk?target=morpho-blue
# HTTP/2 402
# payment-required: … accepts[12]: Arc, Base, Arbitrum, Ethereum, … · 0.002 USDC · Circle Gateway

Machine-readable: /openapi.json (OpenAPI 3.1) · /.well-known/x402 · /llms.txt · /.well-known/agent-card.json

How a payment works

sequenceDiagram
    autonumber
    participant A as Your agent
    participant F as Fuci tool
    participant G as Circle Gateway
    A->>F: GET /api/x402/risk?target=morpho-blue
    F-->>A: 402 Payment Required (price, 12 networks, input schema)
    A->>A: Sign a USDC authorization (EIP-712, no gas)
    A->>F: Same request + payment signature
    F->>G: Verify
    F-->>A: 200 OK + the report
    F->>G: Settle (batched, only if the tool succeeded)

If a tool fails, the payment is never settled. You only pay for answers.

Fuci Risk: know the risk before you put money in

A free A–F rating for any token on Arc or DeFi protocol, built from on-chain and public data only, explained in plain words, with a link to every source. No LLM guessing: when data is missing it says Unknown.

Hard rules cap the grade no matter how good the rest looks: a token under a week old can't score above C, an owner that can mint can't score above D, a hack in the last year caps a protocol at C. Our own token gets no special treatment. Free for people at fuci.family/risk; agents pay 0.002 USDC per check.

Use Fuci from Claude, Cursor or any MCP client

Fuci is on the official MCP Registry as family.fuci.www/fuci and on Smithery.

{ "mcpServers": { "fuci": { "type": "http", "url": "https://www.fuci.family/api/mcp" } } }

Want the assistant to pay from your own wallet, with caps it can't change? Use the local client in mcp/:

{
  "mcpServers": {
    "fuci": {
      "command": "npx",
      "args": ["-y", "https://www.fuci.family/fuci-mcp.tgz"],
      "env": { "FUCI_PRIVATE_KEY": "0x…", "FUCI_MAX_CALL": "0.01", "FUCI_DAILY": "1" }
    }
  }
}

Agent skills: one line, and your AI knows Fuci

Teach Claude Code, Cursor, Codex or any agent that supports skills to use Fuci:

npx skills add fucidotfamily/fuci_family

Paid calls go through Circle Gateway (pay from Arc, Base, Arbitrum, Ethereum, Polygon and more) with the Circle CLI or the Fuci MCP server below. The skills always ask before spending.

An open market for paid APIs

On-chain

The factory source is in contracts/FuciAgentFactory.sol. Fuci earns the 1 USDC creation fee and 1% of each autopilot trade, paid to the treasury; the fees are tracked on DefiLlama with the adapter in defillama/.

Everything inside

Stack: Next.js 16 · Tailwind 4 · viem · @x402/next · @x402/extensions (Bazaar) · @circle-fin/x402-batching (Circle Gateway) · Circle Wallets · Upstash Redis · Claude (optional) · Remotion for the videos.

Run it yourself

git clone https://github.com/fucidotfamily/fuci_family.git && cd fuci_family
npm install
cp .env.example .env.local   # every value is optional for a first look
npm run dev                  # http://localhost:3000

Then open /setup to connect a wallet and create the house agent. Deploying is one click on Vercel: import your fork, then follow the steps below.

Everything on the site is real: Argus launches are read straight from Arc Mainnet, x402 payments use real USDC through Circle Gateway, and stats only count real payments. There is no sample data.

Circle Gateway nanopayments are permissionless: the house agent is a plain wallet key, and payments go to your own wallet, so no Circle account or API key is needed.

1. Open https://www.fuci.family/setup.

   • Step 1: connect your wallet (e.g. Rabby) and add its address in Vercel as FUCI_SELLER_ADDRESS. It receives payments and signs you in to /setup.
   • Step 2: click Generate agent key (generated in your browser) and add it in Vercel as AGENT_PRIVATE_KEY.

2. Make sure Upstash Redis is connected (Vercel → Storage).

3. Redeploy.

4. Back on /setup, Sign in with wallet. Send a little USDC on Arc to the agent address (USDC is Arc's gas too), then click Deposit to Gateway. x402 payments are drawn from the Gateway balance.

5. Check https://www.fuci.family/api/health. When every check is ok: true, the site is live.

6. On /setup, Step 4: Register house agent mints its ERC-8004 identity (a little USDC gas from the agent wallet), and Send 0.05 USDC to validator funds the Tide checker. For the job board, send the agent address free testnet USDC from faucet.circle.com (network: Arc Testnet).

Circle Wallets (CIRCLE_API_KEY + CIRCLE_ENTITY_SECRET) are still supported as an alternative agent wallet once your Circle account has mainnet access.

Optional:

Check it: once the agent is set up, curl -i localhost:3000/api/x402/argus/launches returns 402 Payment Required with real Arc payment requirements.

An agent's owner can switch on Automation on the agent page: pick how often (5 min to 1 day), what to do (Launch Scout, Graduation Watcher, Tide Oracle), an optional focus and a max USDC per day. Every change is signed by the owner's wallet, once; after that the agent runs with no further signatures.

• Its own wallet. Switching automation on creates a wallet for that agent. The key is generated on the server and stored encrypted (AES-256-GCM) in Redis, derived from AGENT_WALLET_SECRET or, if unset, AGENT_PRIVATE_KEY. Changing that secret makes existing agent wallets unreadable, so withdraw first. This is custodial: meant for small balances.
• Funding. The owner clicks Fund (USDC on Arc from their wallet to the agent's). Before a run, the agent moves what it needs into Circle Gateway itself, then pays each tool over x402 with its own key.
• Limits. Never above the daily max; an empty wallet just waits; three failed runs in a row pause it.
• Withdraw sends the Gateway balance and the wallet's USDC (minus a little gas) back to the owner.
• Results go to the agent's History with tx links.

Scheduler (Vercel Hobby runs its own cron only once a day): the tick is POST /api/automation/tick with Authorization: Bearer <tick secret> (both shown on /setup, step 5). Either add QSTASH_TOKEN (Upstash console → QStash) and click Start scheduler, or paste the URL and header into any cron service to call it every 5 minutes. vercel.json also runs it once a day; set CRON_SECRET in Vercel for that call to be accepted.

Notes

• Everything is real: Argus launches are read from Arc Mainnet, payments are real USDC, and stats only count settled payments. There is no sample data.
• Argus addresses and events come from Argus' docs and are checked against mainnet (lib/argus.ts).
• The Tide checker is Fuci's own validator, so treat its scores as Fuci checking its own work in public: anyone can re-run the checks from /api/runs/<hash>.
• Agent outputs and risk grades describe measurable signals. They are not financial advice.

Contributing and security

Issues and pull requests are welcome: see CONTRIBUTING.md. Found a vulnerability? Please follow SECURITY.md instead of opening a public issue. Never commit .env files or keys.