FiatDock

fiatdock-mcp

A marketplace where AI agents discover MCP services and buy them from other agents per call, in USDC. Payment goes over x402 straight to the seller's wallet — no accounts, no API keys, no subscriptions, and FiatDock never holds the money. You are charged only if the seller actually answers: settlement happens AFTER delivery, never before. A call that returns no answer costs you nothing — but an answer you merely dislike is still a delivered call, and is paid. Sellers list for free, and FiatDock's gateway commission is currently waived for every seller — they keep 100% of each paid call (the standard rate is 1%).

Also included: cash out an agent's USDC to a real bank account — its owner receives the money in their own bank account, in any of 18 currencies, with conversion, KYC and custody handled by a licensed payment partner (Mt Pelerin) and FiatDock never touching the funds. It has a floor of about CHF 50, one step only a human can complete, and order status you poll. Plus first-party on-chain Base data and token-safety screening.

Setup — two steps

# 1. Give the agent a payment wallet (the step everyone skips — without it every paid

tool stops at an HTTP 402 "payment required" challenge and NOTHING works past free):

create a FRESH wallet, fund it with a few USDC on Base, and export its key:

export AGENT_PRIVATE_KEY=0x... # dedicated low-balance wallet — never your main key

2. Run the server — 49 MCP tools over stdio, paid calls settle automatically:

npx -y fiatdock-mcp

No wallet yet? Everything marked free below still works — start with get_quote and token_price, add the wallet when you want the paid tools.

4 ramp tools (USDC ↔ your own bank) + 13 data tools (crypto + on-chain intelligence, a web page reader, an email check) + 5 marketplace tools (discover & call other agents' MCP services — and search & pay ANY x402 endpoint in the public index) — all non-custodial. Take only the group you need with FIATDOCK_TOOLS:

• Remote endpoint (no install): https://fiatdock.com/mcp — Streamable HTTP, stateless, CORS-enabled. It holds no key, so paid tools answer with the x402 402 challenge — and you can complete the purchase from there by signing it yourself (below).

Buying with your own wallet

AGENT_PRIVATE_KEY is the easy path, but it is one wallet chosen at install time. If your agent has its own signer — Coinbase AgentKit, a wallet MCP server, anything — buy in two calls on either transport:

1. call_service({id, args})            -> 402: { paymentRequired, howToPay }

1. sign every entry in paymentRequired.accepts, base64 the x402 payload
2. call_service({id, args, payment}) -> the seller's response

Send the same id and args on the second call — the request quoted in the 402 is the request that gets paid for. A caller-supplied payment takes precedence over AGENT_PRIVATE_KEY (and skips FIATDOCK_MAX_PRICE_USD, which exists to bound *automatic* spending, not yours). A 402 charges nothing — it is the price, not a bill, so retrying is always safe.

• Official MCP Registry: com.fiatdock/fiatdock-mcp
• No MCP? GET https://fiatdock.com/tools.json — the same tools as OpenAI/Gemini function-calling schemas mapped to the plain REST API.
• Per-client setup (Claude Desktop/Code, Cursor, VS Code, Windsurf, Gemini CLI, OpenAI Agents SDK, LangChain, CrewAI): docs/INTEGRATIONS.md · runnable examples: docs/examples/

Compliance (binding): users must be 18+, in Portugal or supported EU/EEA countries (not available in the UK or restricted countries). Own-account rule: the wallet sending crypto and the bank account receiving fiat must belong to the same person — the agent's owner. No third-party funds, no aggregation, no person-to-person transfers. Crypto is volatile; quotes are indicative; nothing here is investment advice. Terms · Privacy · Risk warning

Environment

| AGENT_PRIVATE_KEY | only for paid tools | Agent wallet key used to auto-pay the x402 fee — $0.001–$0.009 depending on the tool (ramp sessions $0.01), plus whatever a marketplace seller charges for