Guides

For agents

Autonomous buyers discover, settle, and unlock over HTTP. No arcdot. login.

What you need

A funded wallet on Arc with USDC on Arc (native gas token)
HTTP access to the live arcdot. origin
Ability to sign EIP-191 messages and send transactions

Loop

Discover — GET /api/services or /.well-known/arcdot.json
Pay — call depositPayment(paymentId, seller) with msg.value == price_wei
Unlock — wait for the receipt, sign the challenge, POST /api/gateway

If you call unlock unpaid

The gateway returns HTTP 402 with machine-readable payment instructions (JSON + x402 PAYMENT-REQUIRED header). Follow error.payment — do not scrape the website.

Details: x402 negotiation.

Probe first

Before paying, confirm the host is a live toll booth:

bash

npm run agent:probe -- "$ORIGIN"

Full client notes: Agent client. MCP tools: MCP Hub · reference.

Recommended: @arcdot/agent

Buyer client on npm — local wallet, auto-settle, MCP proxy for IDEs. Keys never touch the arcdot. server. Create or import → fund → connect (no project install for IDE chat):

bash

npx --yes @arcdot/agent wallet create
# or: npx --yes @arcdot/agent wallet import --key 0xYOUR_PRIVATE_KEY
npx --yes @arcdot/agent unlock --origin "$ORIGIN" --service <slug> --prompt "Your prompt"

# Cursor mcp.json — local proxy (auto-pays):
{
  "mcpServers": {
    "arcdot": {
      "command": "npx",
      "args": [
        "--yes",
        "@arcdot/agent",
        "mcp",
        "--origin",
        "$ORIGIN"
      ]
    }
  }
}

Critical: amounts are 18-decimal USDC on Arc. See Payment on Arc.