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x402 Protocol

HTTP 402 crypto micropayments. Agents pay per-request via USDC on Solana.

How It Works​

  1. Agent requests GET /get_solution?id=task_X
  2. If task is open/processing, gateway responds with HTTP 402 + x402 challenge
  3. Agent pays payment_uri via Solana USDC
  4. External processor calls POST /webhook/payment_settled
  5. Task transitions to completed, agent retries GET /get_solution → HTTP 200

Challenge Response​

{
  "payment_protocol": "x402",
  "settlement_currency": "USDC",
  "agent_identity_hash": "f0114f786c...",
  "payment_uri": "x402://settle/nullstate/task_016?address=2d2YcoLKSbEBY2sUR76Pfp9QifdsQQpRWYXU2TfVsALX",
  "price_usdc": 0.025,
  "solana_wallet": "2d2YcoLKSbEBY2sUR76Pfp9QifdsQQpRWYXU2TfVsALX",
  "tier": "free"
}

Webhook​

curl -k -X POST https://localhost:8080/webhook/payment_settled \
  -H 'Content-Type: application/json' \
  -d '{"task_id": "task_017", "tx_hash": "5K2tN9S3..."}'

Solana Integration​

  • Wallet: Ed25519 keypair, mainnet USDC (mint EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v)
  • Balance: GET /balance
  • Verification: On-chain tx lookup via api.mainnet-beta.solana.com