Autonomous Agents: Wallet Identity + Credits

AgentPMT lets autonomous agents buy Agent Credits (100 credits = $1) and invoke marketplace tools and workflows over HTTP. Identity is a wallet signature (no API keys).

1) Identity: A Wallet Address + Signatures

Your agent is identified by an EVM wallet address. To check balances, invoke tools, or fetch and run workflows, your agent signs standardized messages (EIP-191 personal-sign). Credits are attached to that wallet address.

2) If Your Agent Doesn't Have a Wallet: Use AgentAddress

If your agent runtime doesn't already have a wallet, generate one with AgentAddress. AgentAddress runs locally in your browser and produces an address + secret key + recovery phrase.

3) Buying Credits (Two Patterns)

Purchase API supports three flow variants: x402direct (body-based two-step, recommended), x402 v2 header handshake (PAYMENT-REQUIRED/PAYMENT-SIGNATURE), and x402 self-broadcast (submit transaction_hash).

Pattern A: Agent Pays and Credits Itself (Fully Autonomous)

Use this when your agent wallet holds USDC and is allowed to purchase credits directly. This is the simplest flow.

# Option A1: x402direct (recommended, server broadcasts after authorization)
curl -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
  -H "Content-Type: application/json" \
  -d '{ "wallet_address":"0xAGENT_WALLET", "credits": 500, "payment_method":"x402direct" }'

# Then submit authorization in a second call.

# Option A2: x402 v2 header handshake
# Step 1 -> read PAYMENT-REQUIRED, Step 2 -> send PAYMENT-SIGNATURE (base64 JSON).
curl -i -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
  -H "Content-Type: application/json" \
  -d '{ "wallet_address":"0xAGENT_WALLET", "credits": 500, "payment_method":"x402" }'

# Option A3: x402 self-broadcast proof (you submit tx hash after broadcasting on-chain)
curl -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
  -H "Content-Type: application/json" \
  -d '{ "wallet_address":"0xAGENT_WALLET", "credits": 500, "payment_method":"x402", "transaction_hash":"0xYOUR_TX_HASH" }'

Pattern B: Human Sponsors Credits to the Agent Wallet (Recommended Guardrails)

Use this when a human wants to pay from their own wallet, but give the agent only a capped amount of spend power via credits (without sharing the human wallet key).

In this model:

• The agent has its own wallet (for identity and signing requests).
• The human pays USDC from a different wallet.
• The human includes a sponsor signature authorizing which agent wallet should receive the credits for that payment.

# Human sponsors credits to an agent wallet using x402direct
# (The payment authorization "from" is the human wallet; credits are granted to wallet_address.)

curl -s -X POST "https://www.agentpmt.com/api/external/credits/purchase" \
  -H "Content-Type: application/json" \
  -d '{
    "wallet_address":"0xAGENT_WALLET",
    "credits": 500,
    "payment_method":"x402direct",
    "payer_wallet_address":"0xHUMAN_WALLET",
    "sponsor_signature":"0x<signature-by-human-wallet>",
    "authorization": {
      "from":"0xHUMAN_WALLET",
      "to":"0xUSER_CREDIT_WALLET",
      "value":"5000000",
      "valid_after":"0",
      "valid_before":"1700000000",
      "nonce":"0x<32-bytes>",
      "signature":"0x<65-bytes>"
    }
  }'

# sponsor_signature signs this exact message (EIP-191 personal-sign):
agentpmt-external-sponsor
payer:0xhuman_wallet_lower...
recipient:0xagent_wallet_lower...
credits:500
nonce:0x<same-nonce-as-authorization>

If sponsored purchase uses self-broadcast transaction-hash mode instead of authorization mode, the sponsor signature reference line becomes tx:0xYOUR_TX_HASH instead of nonce:....

4) Running Tools and Workflows Autonomously

Once the agent wallet has credits, the agent can:

• create a session nonce
• check credit balance
• list and invoke tools
• list, fetch, and run workflows with wallet-based session tracking