Approvals - Utexo Protocol Docs

After an intent is created, an approval must be added before it can be executed. This endpoint attaches a signed approval to an existing intent. The approval proves the user has authorized the swap and allows it to proceed.

POST /affiliate/v1/intents/{intent_id}/approvals

Request body

The body depends on the approval mechanism returned when the intent was created. It includes the approval type and the data signed by the user.

Permit2 (EVM, Tron)
PSBT (Bitcoin)
Cosign (Solana)

{
  "type": "permit2",
  "signed_data": "0x..."
}

signed_data is the Permit2 signature. See Signing for EVM and Signing for Tron.If the API returns error code 25, the user has not yet approved Permit2 for the selected token. The user must approve Permit2 on-chain before continuing. See Approve for Permit2.

{
  "type": "psbt",
  "signed_data": "cHNid..."
}

signed_data is the signed PSBT, Base64-encoded. See Signing for Bitcoin.RGB USDT sources (rgblock) use the same psbt approval type. See RGB USDT in Utexo Swap.

{
  "type": "cosign",
  "signed_data": {
    "transaction": "02000...",
    "user_address": "F8ZRdxvWEczGyxEBPiYraWCcMjv2sQZxuhh7BGETTDFg"
  }
}

signed_data.transaction is the signed versioned transaction, hex-encoded. See Signing for Solana.

Example

const BASE_URL = "https://api-swap.utexo.com/affiliate";

async function addApproval(intentId: string, approval: object): Promise<void> {
  const response = await fetch(`${BASE_URL}/v1/intents/${intentId}/approvals`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "X-API-Key": process.env.UTEXO_SWAP_API_KEY!,
    },
    body: JSON.stringify(approval),
  });
  if (!response.ok) {
    throw new Error(`Approval failed: ${response.status} ${await response.text()}`);
  }
}