Monero to USDC swap API

Quote, open and track XMR ⇄ USDC swaps on Arbitrum One from your backend, bot or AI agent: a public HTTPS API and a remote MCP server, with no API key, no account and no KYC. Swapper never holds funds.

A quote in one call

A quote needs no key and creates nothing. Pass direction (x2u sells XMR, u2x buys XMR) and amount, what the user sends, as a decimal string (digits and one dot):

curl -sS https://xmrtousdc.xyz/api/v1/agent/swap/quote \
  -H "content-type: application/json" \
  -d '{"direction":"x2u","amount":"0.8","to":"0xYOUR_ARBITRUM_ADDRESS"}'

What to read in the response:

• data.quoteId, data.expiresAt and data.expiresInSec: the order must be created within the 300-second acceptance window, or you quote again.
• data.terms.receive.estimate: the estimated output with every fee inside. guaranteed: false: the provider publishes no minimum receive amount (receive.minimum is null), so the final amount is set when the swap runs.
• data.terms.fees.integratorFee: Swapper's fee (currently 1%), already inside the rate.
• data.terms.minimumSwapUsd, minimumSendEstimate and belowProviderMinimum: the provider's minimum; create refuses a quote below it.
• data.prerequisites (USDC senders): native USDC plus ETH for gas on Arbitrum One, before any order exists.

Know what the user wants to receive? Send receiveAmount instead of amount, with direction: "u2x", and Swapper finds the USDC to send:

curl -sS https://xmrtousdc.xyz/api/v1/agent/swap/quote \
  -H "content-type: application/json" \
  -d '{"direction":"u2x","receiveAmount":"1","to":"YOUR_MONERO_ADDRESS"}'

Open the order and track it

Create the order from the quote alone, with an idempotency-key header: a new random UUID per order, reused only to retry that same create. No confirmation step is required.

KEY=$(uuidgen)   # a new random key per order; reuse it only to retry this create
curl -sS https://xmrtousdc.xyz/api/v1/agent/swap/create \
  -H "content-type: application/json" \
  -H "idempotency-key: $KEY" \
  -d '{"quoteId":"QUOTE_ID"}'

The response carries data.order.orderId, data.destination (the payout address recorded with the order), data.payable, data.deposit (one-time address, exact amount, expiry) and, while payable is true, data.deposit.payment: a wallet-ready transfer (a monero: URI, or an EIP-681 link plus an unsigned ERC-20 transaction). Send it once, unchanged, only if data.destination is the user's own address. Then long-poll the status until terminal is true:

curl -sS "https://xmrtousdc.xyz/api/v1/agent/swap/status/ORDER_ID?waitSec=25&sinceState=waiting_for_funding"

Core endpoints

Every endpoint, error code and order state, with a full JavaScript loop and a system prompt for your agent: REST API reference.

Connect an AI agent over MCP

Agents in MCP clients get the same flow as tools (get_quote, create_swap, get_swap_status, get_funding_options, list_swaps, plan_swap, get_capabilities, create_support_ticket), with no key and no OAuth:

Step-by-step setup for each client, the prompts, an example conversation and the safety model: Monero MCP server.

Rules for a safe integration

• Amounts are decimal strings with digits and one dot ("0.5", never "0,5" or "0.5 XMR"). Never invent or guess addresses or amounts.
• Each quote opens at most one order. A new order needs a new quote and a new idempotency key; a retry reuses both.
• Fund only while payable is true, exactly once, and read the status before showing a deposit again. Paying from an agent's wallet: Agent wallets.
• Honor 429 and Retry-After; long-poll status instead of polling fast.
• Never ask for seed phrases or private keys: Swapper never needs them.

Machine-readable docs

• OpenAPI 3.1 (base https://xmrtousdc.xyz/api/v1) and llms-full.txt, everything an LLM needs to run a swap, in one file.
• Quickstart JSON and capabilities: directions, live chains, limits, validation rules.
• MCP server card (registry name xyz.xmrtousdc/monero-swap).
• autonomous-agent.mjs: a runnable agent (Node 20+, no dependencies) that quotes, creates and checks the payment, and stops before signing unless you plug in a wallet adapter.

Questions

Integration help: agent@xmrtousdc.xyz. Swapping by hand instead? Monero to USDC · USDC to Monero.

Open the swap app →