Create an Intent

Create a new swap intent that describes what the user wants to swap. The intent is created off-chain and later executed on-chain by a resolver.

POST /affiliate/v1/intents

Request

{
  "quote_id": "fe5601fb-60f2-4cb0-8a67-c55bd3640411",
  "refund_address": "0x0000000000000000000000000000000000000000",
  "user_destination_address": "0x0000000000000000000000000000000000000000",
  "user_source_address": "0x0000000000000000000000000000000000000000",
  "user_source_public_key": null
}

Field	Type	Required	Description
`quote_id`	string	Yes	Quote ID returned by `POST /affiliate/v1/quotes/best`
`refund_address`	string	Yes	Address on the source network that receives funds if the swap is refunded
`user_destination_address`	string	Yes	Address on the destination network that receives the swapped asset
`user_source_address`	string	Yes	Address on the source network that provides the funds
`user_source_public_key`	string	Conditional	Required only when the source chain is Bitcoin (including RGB USDT) or Solana
`retail_user_id`	string	No	Your own user identifier, for analytics and user-level tracking

Response

The response contains the intent ID, the deadline, and the data the user must sign.

{
  "intent_id": "8a2d3f92-2a2b-4e4c-9d8a-3c9f92e4a111",
  "deadline_secs": 1761545456,
  "secret_hash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "approval_mechanism": "permit2",
  "params_to_sign": {
    "escrow_contract_address": "0x0000000000000000000000000000000000000000",
    "permit2_contract_address": "0x0000000000000000000000000000000000000000",
    "resolver_deposit_address": "0x0000000000000000000000000000000000000000",
    "nonce": 10000,
    "additional_data": {
      "domain": { },
      "types": { },
      "witness": { },
      "witness_type_string": "ExampleTrade witness)ExampleTrade(address exampleTokenAddress,uint256 exampleMinimumAmountOut)",
      "witness_hash": "0x0000000000000000000000000000000000000000000000000000000000000000"
    }
  }
}

Approval mechanism

The approval flow depends on the source chain and swap type. The value of approval_mechanism may change, and the structure of params_to_sign depends on it. Always check approval_mechanism and handle params_to_sign accordingly.

`approval_mechanism`	Source chain	Signing guide
`permit2`	EVM, Tron	EVM, Tron
`htlc`	Bitcoin	Bitcoin
`rgblock`	Bitcoin (RGB USDT)	RGB USDT
`cosign`	Solana	Solana

Permit2 (EVM, Tron)
HTLC (Bitcoin)
RGB lock (RGB USDT)
Cosign (Solana)

{
  "intent_id": "528d72ae-61cd-4fbc-9940-48ce4104abbb",
  "deadline_secs": 1772124002,
  "secret_hash": "0x19875e12d834bc245b834c4c031d4b89c6354fba4575e44dd26f37d367a44926",
  "approval_mechanism": "permit2",
  "params_to_sign": {
    "escrow_contract_address": "0x8DcbE1aCf345BF5117543f69C3541e318F8e8836",
    "permit2_contract_address": "0x000000000022D473030F116dDEE9F6B43aC78BA3",
    "resolver_deposit_address": "0xF3B3a4edBb93E8eb85B4DBCB1483B2f69f557029",
    "nonce": 499,
    "additional_data": {
      "domain": { },
      "types": { },
      "witness": { },
      "secretHash": "0xabcde...",
      "witness_type_string": "DepositWitness witness)DepositWitness(address resolverDepositAddress,bytes32 secretHash,uint256 deadline)TokenPermissions(address token,uint256 amount)",
      "witness_hash": "0xc77ff4a96e07cede0217fa3bf985d16078f9f1b637ea7b60e8b8c12636c39f7f"
    }
  }
}

domain, types, and witness contain the EIP-712 domain, types, and witness data (shortened here).

{
  "approval_mechanism": "htlc",
  "params_to_sign": {
    "psbt": "cHNidP8BAJ0CAAAAAQEBAQEB...",
    "inputs": [0, 1, 2]
  }
}

psbt is Base64-encoded. inputs lists the input indexes the user must sign.

{
  "approval_mechanism": "rgblock",
  "params_to_sign": {
    "lock_address": "bc1p…",
    "psbt": "cHNid…",
    "witness_invoice": "wvout:…",
    "inputs": [0, 1, 2],
    "asset_id": "rgb:…",
    "asset_amount": 100,
    "lock_anchor_sat": 546
  }
}

The user pays witness_invoice to lock the RGB asset in the HTLC. See RGB USDT in Utexo Swap.

{
  "intent_id": "0a47fbd6-056a-4e4d-a1e3-9b9a1bf947e5",
  "deadline_secs": 1772124152,
  "secret_hash": "0x84edcf73255d3a419a9f12686128d0ef00bfff31e82b110fe160dd0fb60baccf",
  "approval_mechanism": "cosign",
  "params_to_sign": {
    "transaction": "02000..."
  }
}

transaction is a hex-encoded versioned transaction.

Next: submit the signed approval.

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Approval mechanism