generated: '2026-09-19'
method: searched
source: openapi/liquidagent-ai-openapi.yml
docs: https://api.liquidagent.ai/v1/guide
docs_also:
- https://api.liquidagent.ai/llms.txt
- https://api.liquidagent.ai/v1/gas?docs=1
- https://api.liquidagent.ai/.well-known/x402-resources
- https://raw.githubusercontent.com/LiquidAgent/liquidagentx402/main/skills/liquid-gas-sponsor/SKILL.md
summary:
  types: [apiKey, http]
  api_key_in: [header]
  accounts: false
  api_keys_issued: false
  oauth2_flows: []
  model: >-
    No account, no API key, no allowlist. Eleven free operations accept an OPTIONAL wallet identity (SIWX,
    EIP-4361, in a SIGN-IN-WITH-X header) and work anonymously without it - observed live: every free read
    answered 200 with no headers at all. Four paid operations are gated by x402 v2 payment rather than identity:
    the server answers 402 with a PaymentRequired document, the caller signs a USDC authorization for exactly the
    quoted amount and retries with it in an X-PAYMENT (or PAYMENT-SIGNATURE) header. The server holds no key and
    never signs; the caller's own wallet is the only credential anywhere in the system.
schemes:
- name: siwx
  type: apiKey
  in: header
  parameter: SIGN-IN-WITH-X
  description: Sign-In with X wallet identity (EIP-4361). Optional; no payment.
  required: false
  applies_to: [get_v1_guide, get_v1_basket, get_v1_vault_address, get_v1_balance_agent, get_v1_quote, post_v1_create-vault, post_v1_set-weights, post_v1_buy, post_v1_redeem, post_v1_rebalance, post_v1_send]
  observed: All eleven operations answer 200 without the header (probed 2026-09-19), so the scheme is identity, not access control.
  sources: [openapi/liquidagent-ai-openapi.yml]
- name: x402
  type: http
  scheme: x402
  description: Pay-per-call via x402 (exact scheme, EIP-3009 USDC on Base eip155:8453 or Polygon eip155:137). Sign a USDC authorization; no account, no key held by the server.
  required: true
  applies_to: [getV1Signals, postV1Publish, postV1Gas, postV1GasSolana]
  protocol:
    version: 2
    scheme: exact
    challenge: 'HTTP 402; body is the PaymentRequired JSON {x402Version, error, resource, accepts[], extensions}; the same JSON base64-encoded in PAYMENT-REQUIRED and X-PAYMENT-REQUIRED response headers'
    payment_header: X-PAYMENT (PAYMENT-SIGNATURE also accepted on the Solana lane)
    evm_authorization: EIP-3009 transferWithAuthorization on USDC - Base 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, Polygon 0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359; accepts[].extra carries {name USD Coin, version 2, chainId, verifyingContract}
    solana_authorization: one USDC TransferChecked of exactly accepts[].amount to the sponsor's USDC account, sponsor as fee payer, wrapped as {x402Version:2, scheme:exact, network, accepted, payload:{transaction}} and base64d
    payTo: {evm: '0x487b28A4FbbA8Cf46eb6E1d72e6959202Bb75e90', solana: BBcAL97dyJPGmsjQ7pPxCdUsFk1wgZ6jqYQ4DFvCVHkn}
    timeout: maxTimeoutSeconds 60 per accepts[] entry
    erc7677_in_band: On POST /v1/gas JSON-RPC calls HTTP is always 200; an unpaid pm_getPaymasterData returns a JSON-RPC error {code:402, data:<PaymentRequired>} and the payment object goes in params[3].context.x402
    facilitator: PayAI (named in the gas-sponsor SKILL.md)
  sources: [openapi/liquidagent-ai-openapi.yml, https://api.liquidagent.ai/v1/signals (live 402), https://api.liquidagent.ai/v1/gas (live 402)]
signing_is_not_authentication:
  note: >-
    The six transaction builders return unsigned calldata or EIP-712 typed data; the caller signs with the wallet
    that owns the funds and broadcasts to Base itself. That signature authorizes the on-chain action, not the API
    call - the API call needs nothing. Consequently there is nothing to rotate, revoke or leak on the API side.