Agent Workflows

End-to-end examples showing real AI agent sessions performing crosschain tasks with the Across Protocol.

Walk through complete agent workflows — from the user's prompt to the final result. Each example shows every step the agent takes, the API calls it makes, and the data it works with.

Example 1: Bridge USDC Across Chains

User prompt:

Bridge 100 USDC from Arbitrum to Base

Discover supported chains

The agent calls the chains endpoint to confirm Arbitrum and Base are supported and to get their chain IDs.

GET https://app.across.to/api/swap/chains

The agent finds:

Arbitrum — chain ID 42161
Base — chain ID 8453

Look up token addresses

The agent fetches the token list for both chains to find the USDC contract addresses.

GET https://app.across.to/api/swap/tokens?chainId=42161
GET https://app.across.to/api/swap/tokens?chainId=8453

The agent finds:

USDC on Arbitrum: 0xaf88d065e77c8cC2239327C5EDb3A432268e5831 (6 decimals)
USDC on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (6 decimals)

Get a quote

The agent formats the amount (100 USDC = 100000000 with 6 decimals) and requests a quote.

GET https://app.across.to/api/swap/approval
  ?originChainId=42161
  &destinationChainId=8453
  &inputToken=0xaf88d065e77c8cC2239327C5EDb3A432268e5831
  &outputToken=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
  &amount=100000000
  &depositor=0xUserWallet
  &tradeType=minOutput

The response includes:

expectedFillTime: 2 seconds
simulationSuccess: true
approvalTxns: 1 approval needed (first time only)
swapTx: the bridge transaction calldata

Execute token approval

The quote includes an approval transaction because this is the first time bridging USDC through this SpokePool. The agent sends it.

Transaction: Approve SpokePool to spend USDC
Hash: 0xabc123...
Status: Confirmed

On subsequent bridges, this step is skipped — the approval persists.

Execute the bridge

The agent sends the main swap transaction using the calldata from the quote.

Transaction: Deposit 100 USDC into Arbitrum SpokePool
Hash: 0xdef456...
Status: Confirmed in block 284719304

The agent reports back:

Bridged 100 USDC from Arbitrum to Base. Expected fill time: ~2 seconds. Tx: https://arbiscan.io/tx/0xdef456...

Track the deposit

The agent polls the status endpoint until the deposit is filled.

GET https://app.across.to/api/deposit/status
  ?originChainId=42161
  &depositTxHash=0xdef456...

After ~2 seconds:

{
  "status": "filled",
  "fillTxHash": "0x789abc...",
  "destinationChainId": 8453
}

The agent confirms: Transfer complete. 100 USDC arrived on Base.

Try it yourself. Give your agent this prompt:

Bridge 100 USDC from Arbitrum to Base

With the Across skill installed, the agent handles the entire flow autonomously.

Example 2: Bridge + DeFi Deposit

User prompt:

Bridge 100 USDC from Arbitrum to Ethereum, swap to ETH, and deposit into Aave

Discover chains and tokens

The agent resolves chain IDs and token addresses, same as Example 1.

Arbitrum (42161) — USDC: 0xaf88d065e77c8cC2239327C5EDb3A432268e5831
Ethereum (1) — WETH: 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2

The agent identifies this as a cross-token bridge (USDC to WETH) with an embedded action.

Build the embedded action

The agent constructs an Aave deposit action targeting the WETH Gateway on Ethereum.

embedded action

{
  "target": "0x893411580e590D62dDBca8a703d61Cc4A8c7b2b9",
  "functionSignature": "function depositETH(address, address onBehalfOf, uint16 referralCode)",
  "args": [
    { "value": "0x0000000000000000000000000000000000000000", "populateDynamically": false },
    { "value": "0xUserWallet", "populateDynamically": false },
    { "value": "0", "populateDynamically": false }
  ],
  "value": "0",
  "isNativeTransfer": false,
  "populateCallValueDynamically": true
}

The key: populateCallValueDynamically: true tells the MulticallHandler to forward the entire ETH balance from the swap as msg.value to the Aave deposit.

Get a quote with actions

The agent uses POST /swap/approval with the actions array in the body and sets recipient to the MulticallHandler contract.

POST https://app.across.to/api/swap/approval
  ?originChainId=42161
  &destinationChainId=1
  &inputToken=0xaf88d065e77c8cC2239327C5EDb3A432268e5831
  &outputToken=0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2
  &amount=100000000
  &depositor=0xUserWallet
  &recipient=0x924a9f036260DdD5808007E1AA95f08eD08aA569
  &tradeType=exactInput

Body: { "actions": [<embedded action>] }

The response confirms simulationSuccess: true — the full flow (bridge + swap + Aave deposit) has been simulated successfully.

Execute approvals and bridge

The agent sends any required approval transactions, then the main swap transaction.

Transaction: Deposit USDC into Arbitrum SpokePool (with embedded Aave action)
Hash: 0xfed987...
Status: Confirmed

What happens next (handled by the protocol):

A relayer fills the intent on Ethereum, delivering ETH to the MulticallHandler
The MulticallHandler executes the Aave depositETH() call
Aave mints aWETH tokens to the user's address

Confirm the result

The agent tracks the deposit and confirms the full flow completed.

Bridge + Aave deposit complete. 100 USDC on Arbitrum has been converted to an aWETH lending position on Ethereum. Deposit tx: https://arbiscan.io/tx/0xfed987... Expected fill: ~2 seconds.