Billing

Mint a persistent API key via x402 USDC payment

Agents submit a verified Base mainnet USDC transaction hash and receive a persistent ho_live_ API key. Builder tier: 99 USDC = 50K calls/day. Pro tier: 299 USDC = 200K calls/day. Each tx_hash mints at most one key: the hash is claimed atomically before the key is created. The request must carry signature, an EIP-191 personal_sign by the address that sent the USDC Transfer over the exact message "headlessoracle.com x402 mint <tx_hash>" (tx_hash lowercase); it is checked before the hash is claimed, so a wrong signature cannot spend the payer's claim. Only an EOA can mint: smart-contract wallets (ERC-1271) are not supported.

post/v5/x402/mint

Request

  • Base URL: https://headlessoracle.com
  • URL: https://headlessoracle.com/v5/x402/mint
  • Auth: none declared

Request body

tx_hashstring required

Base mainnet USDC transaction hash (0x-prefixed).

tier'builder' | 'pro' required

Desired key tier.

signaturestring required

Payer binding. EIP-191 personal_sign (keccak256("\x19Ethereum Signed Message:\n" + byte length + message)) by the address that sent the USDC Transfer, as 65 bytes of 0x-prefixed hex (r || s || v, v = 27/28 or 0/1). The signer must be an EOA: smart-contract wallets (ERC-1271) are not supported. Message: "headlessoracle.com x402 mint <tx_hash>", with tx_hash lowercase.

networkstring

Optional. "base", "base-mainnet" or "eip155:8453".

emailstring email

Optional. The key is returned in the response as api_key.

Response

Key minted

api_keystring

Your new persistent API key (ho_live_ prefix). Store securely — shown once.

tier'builder' | 'pro'
daily_limitinteger

Changes

No recorded changes to this operation across all 1 revision of this API.