API Overview

Base URL

https://api.daimo.com

Authentication

Endpoints use Bearer token authentication with your API key:

Authorization: Bearer YOUR_API_KEY

Some endpoints accept a client secret instead, passed in the request body or query string. Each session has its own client secret, returned when you create or retrieve the session. Client secrets are safe for client-side use since they only grant access to their specific session.

Credential	Format	Use
API key	UUID	Server-side. Create sessions, retrieve full details.
Client secret	UUID	Client-side, per-session. Set payment method, check status.

Error format

All errors return a JSON body:

{
  "error": {
    "type": "validation_error",
    "code": "invalid_parameter",
    "message": "invalid session create request",
    "param": "body"
  }
}

Field	Type	Description
`type`	`string`	Error category (see below)
`code`	`string`	Machine-readable error code
`message`	`string`	Human-readable description
`param`	`string?`	The parameter that caused the error, if applicable

Error types

Type	Description
`authentication_error`	Missing or invalid credentials
`validation_error`	Invalid request body or parameters
`invalid_request_error`	Valid request but cannot be processed (e.g. resource not found)
`api_error`	Internal server error

HTTP status codes

Code	Meaning
`200`	Success
`201`	Created
`400`	Bad request, validation error
`401`	Unauthorized, missing or invalid API key
`404`	Not found, session does not exist
`500`	Internal server error

Session object

The full session object (returned with API key authentication):

{
  sessionId: string;        // 32-character hex ID
  status: SessionStatus;    // see below
  destination: {
    type: "evm";
    address: string;        // checksum-encoded destination address
    chainId: number;        // e.g. 8453
    chainName: string;      // e.g. "Base"
    tokenAddress: string;   // destination token address
    tokenSymbol: string;    // e.g. "USDC"
    amountUnits?: string;   // requested amount in token units
    calldata?: string;      // hex-encoded calldata for contract calls
    delivery?: {            // set once funds are delivered
      txHash: string;
      receivedUnits: string;
    };
  };
  display: {
    title: string;          // e.g. "Deposit to Acme"
    verb: string;           // e.g. "Deposit"
  };
  paymentMethod: PaymentMethod | null;
  metadata: Record<string, string> | null;
  clientSecret: string;     // per-session client credential
  createdAt: number;        // unix timestamp (seconds)
  expiresAt: number;        // unix timestamp (seconds)
}

Without an API key, metadata and clientSecret are omitted. The destination above shows the EVM shape. For a Solana destination (USDC only), destination is instead:

{
  type: "solana";
  address: string;        // base58 destination address
  tokenAddress: string;   // USDC mint (base58)
  tokenSymbol: string;    // "USDC"
  amountUnits?: string;   // requested amount in token units
  delivery?: {            // set once funds are delivered
    txHash: string;       // Solana transaction signature
    receivedUnits: string;
  };
}

A Solana destination uses the token mint as tokenAddress, omits chainId, chainName, and calldata, and its delivery.txHash is a Solana transaction signature.

SessionStatus

Value	Description
`requires_payment_method`	Waiting for user to choose how to deposit
`waiting_payment`	Payment method set, waiting for deposit transaction
`processing`	Deposit detected, routing funds to destination
`succeeded`	Funds delivered to destination
`bounced`	Delivery failed, funds returned to refund address
`expired`	Session timed out

PaymentMethod

Three variants based on the source chain: EVM:

{
  "type": "evm",
  "receiverAddress": "0x...",
  "source": {
    "address": "0x...",
    "chainId": 1,
    "chainName": "Ethereum",
    "tokenAddress": "0x...",
    "tokenSymbol": "USDC",
    "sentUnits": "10.00",
    "txHash": "0x..."
  },
  "createdAt": 1700000000
}

Tron:

{
  "type": "tron",
  "receiverAddress": "T...",
  "source": {
    "address": "T...",
    "chainId": 728126428,
    "chainName": "tron",
    "tokenAddress": "T...",
    "tokenSymbol": "USDT",
    "sentUnits": "10.00",
    "txHash": "..."
  },
  "createdAt": 1700000000
}

Solana:

{
  "type": "solana",
  "source": {
    "address": "So1...",
    "chainId": 501,
    "chainName": "solana",
    "tokenAddress": "EPjF...",
    "tokenSymbol": "USDC",
    "sentUnits": "10.00",
    "txHash": "..."
  },
  "createdAt": 1700000000
}

The source field is populated once the user’s deposit transaction is detected. Before that, only type, receiverAddress (for EVM/Tron), and createdAt are present. EVM and Tron are receiver-address flows. Solana is a sign-and-send flow: instead of a receiverAddress, the response returns a transaction payload for the wallet to execute in one click.

Create payment method response

When creating a payment method, chain-specific fields are returned alongside the session:

Tron: tron.receiverAddress (the Tron USDT address to send to), tron.expiresAt, and optionally tron.deeplinks.trustWallet for opening Trust Wallet’s USDT on Tron send flow
Solana: solana.serializedTx (hex-encoded serialized transaction for the wallet to sign and submit)
EVM: no additional fields; the deposit address is the session’s EVM deposit address

Overview

Sessions

External Integrations

Webhooks

API Overview

Base URL

Authentication

Error format

Error types

HTTP status codes

Session object

SessionStatus

PaymentMethod

Create payment method response

​Base URL

​Authentication

​Error format

​Error types

​HTTP status codes

​Session object

​SessionStatus

​PaymentMethod

​Create payment method response

Base URL

Authentication

Error format

Error types

HTTP status codes

Session object

SessionStatus

PaymentMethod

Create payment method response