Demo seller

Use the demo merchant store to try out Arc Pay wallet with agentic commerce protocol (ACP)

https://merchant-demo.arcpay.ai

Obtain an API key

To obtain an API key, log into your Arc Pay account and head to the My API keys page. Keep your API key secret and do not share it with anyone.

Authentication

Authentication is done via bearer auth. Use your API key as the bearer token in the request header:

curl https://arcpay.ai/account \
  -H "Authorization: Bearer sk_test_YOUR_API_KEY"

Test mode

Arc Pay supports test mode for testing and development. Test mode uses blockchain testnets & payment sandboxes to avoid real financial risks.

To run in test mode, use the API key with prefix sk_test_. Live mode API keys have the prefix sk_live_.

Additionally, objects returned by the API will have the live flag set to false to indicate that the object is in test mode.

{
  "object": "payment",
  "id": "pay_lb1veJWQWjzEwjo6tqvC5",
  "live": false,
  ...
}

Resources

Idempotency

The API includes idempotency to ensure that retrying a request won't accidentally repeat the same operation.

To use idempotency, include the Idempotency-Key header in the request (e.g. UUID v4 or similar alphanumeric).

If the same request with the same idempotency key is received multiple times, the same response is returned, even for failed requests.

Idempotency keys expire after 24 hours.

Only POST requests support idempotency key (GET and DELETE requests are idempotent by design).

curl https://arcpay.ai/deposits \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sk_test_YOUR_API_KEY" \
  -H "Idempotency-Key: OHGqyQ9oXRZQHGbv" \
  -d '{ "type": "testnet_faucet", "currency": "USDC" }'

Agentic Wallet (MCP)

The Agentic Wallet MCP lets your AI agents pay for physical or digital goods and services.

https://arcpay.ai/wallet

Use the same authentication method as the API.

Agentic Wallet MCP accepts streamable HTTP connections.

Agentic Commerce Protocol (ACP)

Arc Pay supports the Delegated Payments flow of ACP.

This allows merchants to accept payments in their stores from their customers' AI agents.

Arc Pay extends ACP with the following features:

To start accepting payments from AI agents via Arc Pay, the merchant must include Arc Pay as the payment provider in all ACP Checkout Session responses:

# In all ACP Checkout Session responses

{
  "id": "checkout_session_123",
  ...,
  "payment_provider": {
    "provider": "arcpay",
    "supported_payment_methods": [
      "wallet"
    ]
  }
}

Then, the AI agents can use the wallet payment method with Arc Pay to pay for the checkout session using ACP's Delegated Payments flow:

POST /agentic_commerce/delegate_payment

{
  "payment_method": {
    "type": "wallet"
  },
  "allowance": {
    "reason": "one_time",
    "max_amount": 2000,
    "currency": "usd",
    "checkout_session_id": "cart_y6W9dpzxpAzQRmtfr9lUC",
    "merchant_id": "acme",
    "expires_at": "2025-11-30T09:00:00.00Z"
  },
  "risk_signals": [],
  "metadata": {
    "campaign": "q4"
  }
}

Upon checkout competion, the merchant will receive a secret token that can be used to pull the payment from the customer's wallet, up to the authorized limit of the mandate:

POST /payment_captures

{
  "amount": "20",
  "currency": "USDC",
  "granted_mandate_secret": "paym_eNSM2UiaOaUdlfKU6_secret_2k8ZabXp..."
}