quickstart

Up and running in 5 minutes.

Create an account, get a wallet and an API key, and give your agent its first card. The sandbox runs entirely on your machine, no signup needed to try it.

1 · Create an account

curl -X POST https://api.a-card.cc/v1/signup \
  -d '{"email": "you@company.com"}'

Returns an account, a prepaid wallet, and an API key.

2 · Fund your wallet

curl -X POST https://api.a-card.cc/v1/wallet/fund \
  -H "Authorization: Bearer sk_live_..." \
  -d '{"amount_cents": 50000}'

All amounts are integer cents. 500.00 = 50000.

3 · Connect your agent

npx -y @a-card/mcp

That's it. Your agent can now mint cards and pay, inside your rules.

MCP setup

Add a·card to Claude Desktop or any MCP-compatible agent. Runs locally over stdio, or point at our hosted endpoint over Streamable HTTP.

{
  "mcpServers": {
    "acard": {
      "command": "npx",
      "args": ["-y", "@a-card/mcp"],
      "env": { "ACARD_API_KEY": "sk_live_..." }
    }
  }
}

REST API

The MCP server is a thin adapter over this API. Agents and humans hit the same endpoints, with the same guardrails.

METHOD
ENDPOINT
DESCRIPTION

{{ ep.method }}

{{ ep.path }}

MCP tools

{{ tool.name }}

Approvals

Any charge over the card's approval threshold declines as pending_human_approval and lands in your queue. Nothing moves until you decide.

Approving mints a one-time grant bounded to that exact amount. The agent retries the charge, the grant is consumed, the payment settles. Denying releases nothing. The money never left.

Card limits

Every card carries its own rules, set at creation:

budget_centsTotal the card can ever spend.

per_txn_centsMaximum for any single charge.

allowed_mccsMerchant categories the card works at.

velocityMax charges per hour / per day.

approval_threshold_centsCharges above this ask you first.

single_useCard closes itself after one successful charge.