## Documentation Index

Fetch the complete documentation index at: [/llms.txt](https://docs.relay.link/llms.txt)

Use this file to discover all available pages before exploring further.

Relay is a multichain payments network. You define the **Intent** (what the user wants), and Relay handles the **Execution** (how to get there).Follow this 5-step flow to integrate Relay into your application:

### 1. Configure

To see how fast and simple Relay makes transacting cross-chain, let’s bridge real assets between inexpensive L2s—Base and Arbitrum.**Prerequisites:**

- **Base URL:**`https://api.relay.link`
- **Environment:** Node.js installed
- **Wallet:** An EOA with a small amount of ETH (~$2.00 USD equivalent) on Base

### API key Provisioning

Create an API key in the [Relay Dashboard](https://dashboard.relay.link/) to raise your rate limits.

See [API keys and Rate Limits](https://docs.relay.link/references/api/api-keys) for usage and limits.

## Chain Configuration

For chain metadata we recommend querying the [chains API](https://docs.relay.link/references/api/get-chains) in your application. This will return some valuable information about the chain, we’ve provided a sample below:

Response

Request

```
{
  "chains": [{
      "id":10,
      "name":"optimism",
      "displayName":"Optimism",
      "httpRpcUrl":"https://optimism.publicnode.com",
      "wsRpcUrl":"wss://optimism.publicnode.com",
      "explorerUrl":"https://optimistic.etherscan.io",
      "explorerName":"Optimism Etherscan",
      "depositEnabled":true,
      "tokenSupport":"All",
      "disabled":false,
      "partialDisableLimit":0,
      "blockProductionLagging":false,
      "currency":{
          "id":"eth",
          "symbol":"ETH",
          "name":"Ether",
          "address":"0x0000000000000000000000000000000000000000",
          "decimals":18,
          "supportsBridging":true
      },
      "withdrawalFee":1,
      "depositFee":0,
      "surgeEnabled":false,
      "featuredTokens":[
          {
            "id":"eth",
            "symbol":"ETH",
            "name":"Ether",
            "address":"0x0000000000000000000000000000000000000000",
            "decimals":18,
            "supportsBridging":true,
            "metadata":{
                "logoURI":"https://assets.relay.link/icons/1/light.png"
            }
          }
      ],
      "erc20Currencies":[
          {
            "id":"sipher",
            "symbol":"SIPHER",
            "name":"Sipher",
            "address":"0xb94944669f7967e16588e55ac41be0d5ef399dcd",
            "decimals":18,
            "supportsBridging":true,
            "withdrawalFee":1,
            "depositFee":0,
            "surgeEnabled":false
          }
      ],
      "solverCurrencies":[
        {
          "id":"sipher",
          "symbol":"SIPHER",
          "name":"Sipher",
          "address":"0xb94944669f7967e16588e55ac41be0d5ef399dcd",
          "decimals":18
        },
      ],
      "iconUrl":"https://assets.relay.link/icons/10/light.png",
      "contracts":{
        "multicall3":"0xca11bde05977b3631167028862be2a173976ca11",
        "multicaller":"0x0000000000002bdbf1bf3279983603ec279cc6df",
        "onlyOwnerMulticaller":"0xb90ed4c123843cbfd66b11411ee7694ef37e6e72",
        "relayReceiver":"0xa5f565650890fba1824ee0f21ebbbf660a179934",
        "erc20Router":"0xf5042e6ffac5a625d4e7848e0b01373d8eb9e222",
        "approvalProxy":"0xbbbfd134e9b44bfb5123898ba36b01de7ab93d98",
        "v3":{
          "erc20Router":"0xb92fe925dc43a0ecde6c8b1a2709c170ec4fff4f",
          "approvalProxy":"0xccc88a9d1b4ed6b0eaba998850414b24f1c315be"
        }
      },
      "vmType":"evm",
      "baseChainId":1,
      "solverAddresses":[
          "0xf70da97812cb96acdf810712aa562db8dfa3dbef"
      ],
      "tags":[],
      "protocol":{
          "v2":{
            "chainId":"optimism",
            "depository":"0x4cd00e387622c35bddb9b4c962c136462338bc31"
          }
      }
  }]
}
```

See all 87 lines

```
curl -X GET "https://api.relay.link/chains"
```

The endpoint exposes a vast amount of chain metadata but the important things to note are:

- `vmType`: This is the type of virtual machine that the chain uses (SVM, EVM, BVM, etc).
- `id`: This is the chain id of the chain. Some chains like Bitcoin/Solana/Tron have a custom id that the Relay team chose upon deployment.
- `disabled`: This is a boolean that indicates if the chain is disabled. When incidents arise we may disable a chain to prevent users from interacting with it.
- `blockProductionLagging`: This boolean indicates if the chain is lagging in block production. You can use this to let your users know about degraded Relay performance in real time.

### 2. Quote

Every action in Relay starts with a Quote.The [quote endpoint](https://docs.relay.link/references/api/get-quote-v2) handles all of your use cases, whether it’s a [**bridge**](https://docs.relay.link/use-cases/bridging), [**swap**](https://docs.relay.link/use-cases/cross-chain-swaps), or [**cross-chain call**](https://docs.relay.link/use-cases/calling). It calculates fees, finds the best route, and generates the transaction data.

## Request

As an example, let’s consider the scenario of bridging 0.0001 ETH from Base (Chain ID 8453) to Arbitrum One (Chain ID 42161):

_Note: the `requestId` will be unique to every request._

Request

Response

```
curl -X POST "https://api.relay.link/quote/v2" \
-H "Content-Type: application/json" \
-d '{
  "user": "YOUR_WALLET_ADDRESS",
  "originChainId": 8453,
  "destinationChainId": 42161,
  "originCurrency": "0x0000000000000000000000000000000000000000",
  "destinationCurrency": "0x0000000000000000000000000000000000000000",
  "amount": "100000000000000",
  "tradeType": "EXACT_INPUT"
}'
```

```
{
  "steps": [
    {
      "id": "deposit",
      "action": "Confirm transaction in your wallet",
      "description": "Deposit funds to the relayer to execute the bridge",
      "kind": "transaction",
      "requestId": "0x8a9b3c...",
      "items": [
        {
          "status": "incomplete",
          "data": {
            "from": "YOUR_WALLET_ADDRESS",
            "to": "0xf70da97812cb96acdf810712aa562db8dfa3dbef",
            "data": "0x00fad611...",
            "value": "100000000000000",
            "chainId": 8453,
            "gas": "150000",
            "maxFeePerGas": "100000000",
            "maxPriorityFeePerGas": "100000000"
          },
          "check": {
            "endpoint": "/intents/status?requestId=0x8a9b3c...",
            "method": "GET"
          }
        }
      ],
      "depositAddress": ""
    }
  ],
  # ...
  "fees": {
    "gas": {
      "amount": "21000",
      "currency": {
        "chainId": 8453,
        "address": "0x0000000000000000000000000000000000000000",
        "symbol": "ETH",
        "name": "Ether",
        "decimals": 18
      },
      "amountUsd": "0.01"
    },
    "relayer": {
      "amount": "5000000000000",
      "currency": {
        "chainId": 8453,
        "address": "0x0000000000000000000000000000000000000000",
        "symbol": "ETH",
        "name": "Ether",
        "decimals": 18
      },
      "amountUsd": "0.02"
    }
  },
  "details": {
    "operation": "bridge",
    "sender": "YOUR_WALLET_ADDRESS",
    "recipient": "YOUR_WALLET_ADDRESS",
    "timeEstimate": 15,
    "currencyIn": {
      "amount": "100000000000000",
      "currency": {
        "chainId": 8453,
        "address": "0x0000000000000000000000000000000000000000",
        "symbol": "ETH",
        "decimals": 18
      }
    },
    "currencyOut": {
      "amount": "95000000000000",
      "currency": {
        "chainId": 42161,
        "address": "0x0000000000000000000000000000000000000000",
        "symbol": "ETH",
        "decimals": 18
      }
    },
    "totalImpact": {
      "usd": "-0.02",
      "percent": "-0.50"
    },
    "rate": "0.95"
  }
}
```

### 3. Execute

The [quote endpoint](https://docs.relay.link/references/api/get-quote-v2) returns a `steps` array. Think of this as a recipe your application must follow. You need to iterate through these steps and prompt the user to sign or submit them.

### The Logic

For a simple ETH bridge, the `steps` array contains a single transaction item. To execute it:

- **Check the Step Kind:** Identify if the step is a `transaction` (submit to chain) or a `signature` (sign off-chain).
- **Execute:** For transactions, submit the provided `data`, `to`, `value`, and `chainId` using the user’s wallet. For signatures, follow the `signatureKind` provided in the step item to sign the `message`.

### The Script (Node.js / Viem example)

Copy the script below to execute the transaction returned by the Quote in Step 2. You’ll need to add the wallet connection logic using your preferred provider.

```javascript
// npm install viem
import { createWalletClient, http } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import { base } from 'viem/chains';

// 1. Setup Wallet (Base)
//Initialize your wallet using a provider or your preferred method
const account = {}
const client = createWalletClient({
  account,
  chain: base,
  transport: http()
});

// 2. The Quote from Step 2 (Paste JSON response)
const quote = { /* PASTE_FULL_JSON_RESPONSE_HERE */ };

async function execute() {
  console.log("🚀 Starting Execution...");

// Iterate through steps (usually just 1 for ETH bridge)
  for (const step of quote.steps) {
    //Although there is an array of items, you can safely select the first item
    //as there is just one returned
    const item = step.items[0]
    if (step.kind === 'transaction') {
      console.log(`Submitting Transaction...`);

// 3. Send Transaction
      const hash = await client.sendTransaction({
        to: item.data.to,
        data: item.data.data,
        value: BigInt(item.data.value),
        chain: base
      });

//4. Optional but you may want to wait for the transaction receipt
      //to ensure that the origin transaction was successfully submitted.

console.log(`✅ Bridge Initiated: ${hash}`);
      console.log(`requestId: ${step.requestId}`); // Save this for Step 4!
    }
  }
}

execute();
```

### 4. Monitor

Once you submit the transaction, the Relay Solver detects the deposit and fills the request on the destination chain.Use the [status endpoint](https://docs.relay.link/references/api/get-intents-status-v3) with the `requestId` located inside each step object in your [quote response](https://docs.relay.link/references/api/quickstart#request) to track status and confirm success. You can also use the `check.endpoint` property inside the step item object as the endpoint for checking the status of the request.

_Note: Replace with the requestId returned in your quote_

Request

Response

```
curl "https://api.relay.link/intents/status/v3?requestId=0x20538510fd9eab7a90c3e54418f8f477bfef24d83c11955a8ca835e6154b59d3"
```

```
{
  "status": "success",
  "inTxHashes": [
    "0x9421772820b92c239162341a17994b4ad8706c974af2ebf88084a1b3b614d328"
  ],
  "txHashes": [
    "0xef2a71eb2ddd952b31f7b552e133d3af048e4be30a568f2bea54a36d8f3b12cd"
  ],
  "updatedAt": 1767385462193,
  "originChainId": 8453,
  "destinationChainId": 56
}
```

Poll this endpoint once per second. For a real-time status stream you can subscribe to Relay’s [**websocket server**](https://docs.relay.link/references/api/api_guides/websockets).

### 5. Optimize

You have successfully executed your first cross-chain transaction with Relay!
Check out some of the advanced features we offer to customize the experience:

- [**App Fees**](https://docs.relay.link/features/app-fees): Monetize your integration by adding a fee (in bps) to every quote. Revenue is collected automatically in USDC.
- [**Smart Accounts**](https://docs.relay.link/references/api/api_guides/smart_accounts/smart-accounts): Use [ERC-4337](https://docs.relay.link/references/api/api_guides/smart_accounts/erc-4337) and [EIP-7702](https://docs.relay.link/references/api/api_guides/smart_accounts/eip-7702) to enable _Gas Sponsorship_ and _Atomic Batching_ (e.g., Approve + Swap in one click).
- [**Transaction Indexing**](https://docs.relay.link/references/api/api_guides/transaction-indexing): Handle complex settlement scenarios, like tracking complex same-chain wraps or transfers.