Quickstart

Garden’s API allows you to integrate our trustless Bitcoin bridge with flexible levels of control. This guide walks through the fastest way to set up a working integration, For advanced use cases and customization options, refer to our Cookbook. If you are new to atomic swaps, read our intent flow to get started.

High level flow

1. Fetch a quote for an asset pair and amount.

2. Authenticate using an API key or wallet signature.

3. Create the order with selected quote.

4. Initiate the order by sending funds to the HTLC.

5. Track order status to confirm completion.

Fetch quote

To get started, fetch a quote using the /quote endpoint. This returns one or more available strategies from Garden's solver network, along with corresponding rates. Choose a strategy and save its strategy_id for order creation.

curl -X 'GET' \
 'https://api.garden.finance/quote/?order_pair=<source_chain>:<source_asset>::<destination_chain>:<destination_asset>&amount=<amount>&exact_out=<true/false>&affiliate_fee=<affiliate_fee_in_bps>' \
  -H 'accept: application/json'

Parameters:

• order_pair: Build the order pair in the above format using chain and atomicSwapAddress of the required assets from the /info endpoint.
• amount: In smallest units based on the exact_out flag.
• exact_out: Indicates whether the quote should be fetched for an exact output amount. If set to true, the quote will calculate the required input amount to achieve the specified output. If set to false, the quote will calculate the expected output for a given input amount.
• affiliate_fee:The total affiliate fee in basis points (bps), more details here.

Authenticate

Authentication is required before you can interact with the Garden protocol.

Option 1: API key (recommended)

This is the simplest method. Contact the Garden team in the townhall to request an API key. Once you receive it, include it in the request headers using "api-key" as the key and your API key as the value for all authenticated requests.

Option 2: Wallet-based auth (SIWE)

You can also authenticate via Sign-In With Ethereum (SIWE). This flow returns a JWT for use in subsequent requests. Refer to Authentication for more details.

Create order

With authentication in place and a quote selected, you can now create the order. Include all order details, along with the strategy_id from the previous step.

curl -X 'POST' \
  'https://api.garden.finance/relayer/create-order' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer <authorization_token>' \ # in the case of SIWE
  -H 'api-key: <API-key>' \ # in the case of API keys
  -d '{
    "source_chain": "<source_chain>",
    "source_asset": "<source_asset>",
    "source_amount": "<source_amount>",
    "initiator_source_address": "<initiator_source_address>",
    "destination_chain": "<destination_chain>",
    "destination_asset": "<destination_asset>",
    "destination_amount": "<destination_amount>",
    "initiator_destination_address": "<initiator_destination_address>",
    "nonce": "<nonce>",
    "affiliate_fees": [
      {
        "address": "<affiliate_address_1>",
        "chain": "<chain_1>",
        "asset": "<asset_1>",
        "fee": <affiliate_fee_1>
      },
      {
        "address": "<affiliate_address_2>",
        "chain": "<chain_2>",
        "asset": "<asset_2>",
        "fee": <affiliate_fee_2>
      },
      ...
    ],
    "additional_data": {
      "strategy_id": "<strategy_id>",
      "bitcoin_optional_recipient": "<user_bitcoin_address>",
    }
  }'

Your affiliate fee can be split and sent to multiple addresses as shown above. You can define nonce as any random string that is unique to the order.

For non-Bitcoin swaps, provide both initiator_source_address and initiator_destination_address.

For Bitcoin swaps:

• If Bitcoin is the source chain, set initiator_source_address to null.
• If Bitcoin is the destination chain, set initiator_destination_address to null.

The order is considered successfully created and matched if you receive a valid order object response from the getOrder endpoint.

Initiate order

Once matched, the user must initiate the swap. The process differs slightly depending on the source chain. For Bitcoin, the user must send the exact amount of funds to the order.source_swap.swap_id address.

For EVM chains, initiation can be done directly via smart contract or Garden's API.

To initiate, the user must sign the HTLC initiation message using their wallet provider's EIP-712 typed data signing method. This signature authorizes the HTLC contract to lock tokens in escrow with the specified parameters. The signature is used for contract initialization.

1. The user must call the eip712domain() function on the HTLC contract that returns the eip712 domain data. Sample EIP712domain data:

  [ eip712Domain method Response ]
  name                string    :  HTLC
  version             string    :  1
  chainId             uint256   :  42161
  verifyingContract   address   :  0x6b6303fAb8eC7232b4f2a7b9fa58E5216F608fcb

2. The initiation message must be in the following format:

HTLC initiation message format:

{
    address redeemer;
    uint256 timelock;
    uint256 amount;
    bytes32 secretHash;
}

3. The message, along with the domain data, must be signed with the wallet, and the signature is sent with the initiate request to the relayer.

curl -X 'POST' \
  'https://api.garden.finance/relayer/initiate' \
  -H 'accept: application/json' \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer <authorization_token>' \
  -d '{
  "order_id": "<order_id>",
  "signature": "<signature>",
  "perform_on": "Source"
}'

On success, the response contains the transaction hash of the initiate event.

Expected response:

{
  "result": "<tx_id>",
  "status": "Ok"
}

Get order

Use the orders endpoint to track the order status.

curl -X 'GET' \
  'https://api.garden.finance/orders/id/<order_id>

If order.destination_swap.redeem_tx_hash is populated with a tx hash, the swap has completed successfully and the destination asset has been redeemed on the user’s behalf.