zerion-trails-deposit

Zerion — Trails DeFi Vault Deposit

Bridge tokens from any chain and deposit directly into a DeFi vault on Polygon in a single intent, powered by Trails. Trails handles routing, cross-chain settlement, and the vault deposit call atomically. Pair with the Zerion CLI to fund the wallet and verify the resulting vault position.

Setup

1. Get a Trails API key

Visit https://dashboard.trails.build to create an account and generate a key.

2. Install

# Widget or hooks (React / Next.js) + calldata encoding
npm install 0xtrails viem

# Direct API (Node.js / backend)
npm install @0xtrails/api viem

---

When to use

• "Deposit USDC into [vault] on Polygon"
• "Bridge ETH from Ethereum and deposit into Aave on Polygon"
• "Stake into a yield vault on Polygon from any chain"
• "Put my tokens to work on Polygon"
• Any Aave/Morpho lending market or custom ERC-4626 vault on Polygon

Polygon chain ID: 137
Polygon chain name (widget/hooks): "polygon"

Common deposit tokens on Polygon:

Symbol	Address
USDC (native)	0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359
USDC.e	0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174
USDT	0xc2132D05D31c914a87C6611C10748AEb04B58e8F
WETH	0x7ceB23fD6bC0adD59E62ac25578270cFf1b9f619
WMATIC / POL	0x0d500B1d8E8eF31E21C99d1Db9A6444d3ADf1270

---

Zerion CLI integration

Trails handles the bridge + vault deposit; the Zerion CLI handles funding the wallet beforehand and confirming the vault position afterward. Install with npm i -g zerion-cli.

End-to-end flow

# 1. Fund the wallet (shows EVM + Solana deposit addresses)
zerion wallet fund --wallet agent-bot

# 2. Confirm the source-chain balance is in place before quoting
zerion portfolio --wallet agent-bot

# 3. Run the Trails deposit (Widget / hooks / API — see sections below)

# 4. Verify the vault position appeared on Polygon (DeFi positions)
zerion portfolio --wallet agent-bot
zerion analyze agent-bot --chain polygon --positions defi

The Trails SDK runs against the same EVM address that zerion wallet list reports — pass that address as ownerAddress / userAddress and use the vault contract as destinationToAddress / to.recipient in any of the integration modes below.

---

Core concept: placeholder amount

Trails deposits are EXACT_INPUT — the user specifies the input amount and the vault receives the computed settled amount. Because the final amount isn't known at calldata encoding time, import and use TRAILS_ROUTER_PLACEHOLDER_AMOUNT from 0xtrails:

import { TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'

// Trails replaces this with the real settled amount at execution time
args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, receiverAddress]

Do not use this placeholder for functions that read the token balance internally (e.g. deposit(address receiver) without an explicit amount arg).

---

Integration: Widget (React / Next.js)

Import from 0xtrails/widget. Components are self-contained and take apiKey directly.

Fund widget — custom vault via calldata

import { Fund } from '0xtrails/widget'
import { TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'
import { encodeFunctionData } from 'viem'

const erc4626Abi = [
  {
    name: 'deposit',
    type: 'function',
    inputs: [
      { name: 'assets', type: 'uint256' },
      { name: 'receiver', type: 'address' },
    ],
    outputs: [{ name: 'shares', type: 'uint256' }],
  },
] as const

function VaultDepositWidget({
  vaultAddress,
  userAddress,
}: {
  vaultAddress: `0x${string}`
  userAddress: `0x${string}`
}) {
  const calldata = encodeFunctionData({
    abi: erc4626Abi,
    functionName: 'deposit',
    args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, userAddress],
  })

  return (
    <Fund
      apiKey="YOUR_TRAILS_API_KEY"
      to={{
        recipient: vaultAddress,
        currency: "USDC",
        chain: "polygon",
        calldata,
      }}
      onFundingSuccess={({ sessionId }) => {
        console.log('Deposit complete:', sessionId)
      }}
      onFundingError={({ error }) => console.error(error)}
    />
  )
}

Earn widget — for yield/lending protocols

For supported protocols (Aave, Morpho, Yearn, Compound), use the Earn component with composable actions — no manual ABI encoding needed:

import { Earn } from '0xtrails/widget'

function AaveDepositWidget() {
  return (
    <Earn
      apiKey="YOUR_TRAILS_API_KEY"
      onEarnSuccess={({ sessionId }) => {
        console.log('Earned:', sessionId)
      }}
    />
  )
}

For a specific Polygon lending market, add a to config:

<Earn
  apiKey="YOUR_TRAILS_API_KEY"
  to={{
    chain: "polygon",
    currency: "USDC",
  }}
  onEarnSuccess={({ sessionId }) => console.log(sessionId)}
/>

Widget props reference:

Prop	Type	Description
apiKey	string	Trails API key (required)
to.recipient	string	Vault contract address
to.currency	string	Token symbol or address
to.chain	string | number	Chain name, ID, or viem Chain
to.calldata	string	ABI-encoded deposit call (use TRAILS_ROUTER_PLACEHOLDER_AMOUNT)
to.amount	string	Fixed deposit amount (optional)
paymentMethod	string	"CONNECTED_WALLET" (default), "CRYPTO_TRANSFER", "CREDIT_DEBIT_CARD", "EXCHANGE"

---

Integration: Headless hooks (React + custom UI)

Import hooks from 0xtrails. Hooks require TrailsProvider context.

Provider setup

import { TrailsProvider } from '0xtrails'

export default function RootLayout({ children }: { children: React.ReactNode }) {
  return (
    <TrailsProvider trailsApiKey="YOUR_TRAILS_API_KEY">
      {children}
    </TrailsProvider>
  )
}

Aave deposit via composable actions

For supported protocols, use lend() from 0xtrails — Trails handles the contract calls internally:

import { useTrailsSendTransaction, lend, useEarnMarkets } from '0xtrails'

function AaveDepositButton({ amount }: { amount: string }) {
  const { data: markets } = useEarnMarkets({ chain: 'polygon', provider: 'aave' })

  const { sendTransaction, isPending } = useTrailsSendTransaction({
    actions: [
      lend({
        marketId: 'polygon-usdc-aave-v3-lending', // use useEarnMarkets to discover IDs
        amount,
      }),
    ],
  })

  return (
    <button onClick={() => sendTransaction()} disabled={isPending}>
      {isPending ? 'Depositing...' : 'Deposit to Aave on Polygon'}
    </button>
  )
}

Use useEarnMarkets to discover available marketId values at runtime rather than hardcoding them:

import { useEarnMarkets } from '0xtrails'

function MarketPicker() {
  const { data: markets } = useEarnMarkets({
    chain: 'polygon',
    type: 'lending',      // optional: 'lending' | 'vault'
    provider: 'aave',     // optional: filter by protocol
    sortBy: 'apy',        // optional
  })

  return (
    <ul>
      {markets?.map(m => (
        <li key={m.marketId}>{m.name} — {m.apy}% APY</li>
      ))}
    </ul>
  )
}

Custom vault deposit via calldata

For protocols not natively supported by Trails, encode calldata manually:

import { useTrailsSendTransaction, TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'
import { encodeFunctionData } from 'viem'

const erc4626Abi = [
  {
    name: 'deposit',
    type: 'function',
    inputs: [
      { name: 'assets', type: 'uint256' },
      { name: 'receiver', type: 'address' },
    ],
    outputs: [{ name: 'shares', type: 'uint256' }],
  },
] as const

function useCustomVaultDeposit(vaultAddress: `0x${string}`, userAddress: `0x${string}`) {
  const { sendTransaction, isPending } = useTrailsSendTransaction()

  const deposit = () => {
    const calldata = encodeFunctionData({
      abi: erc4626Abi,
      functionName: 'deposit',
      args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, userAddress],
    })

    sendTransaction({
      to: {
        recipient: vaultAddress,
        currency: "USDC",
        chain: "polygon",
        calldata,
      },
    })
  }

  return { deposit, isPending }
}

---

Integration: Direct API (Node.js / backend)

Full control over quote → commit → execute → wait. Use for server-side automation or non-React environments.

import { TrailsApi, TradeType } from '@0xtrails/api'
import { TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'
import { encodeFunctionData } from 'viem'

const trailsApi = new TrailsApi('YOUR_TRAILS_API_KEY')

const erc4626Abi = [
  {
    name: 'deposit',
    type: 'function',
    inputs: [
      { name: 'assets', type: 'uint256' },
      { name: 'receiver', type: 'address' },
    ],
    outputs: [{ name: 'shares', type: 'uint256' }],
  },
] as const

async function depositToPolygonVault(params: {
  userAddress: string
  vaultAddress: string
  depositTokenAddress: string   // token the vault accepts on Polygon
  originChainId: number
  originTokenAddress: string
  originTokenAmount: bigint     // in source token's smallest unit
}) {
  const { userAddress, vaultAddress, depositTokenAddress, originChainId, originTokenAddress, originTokenAmount } = params

  // Encode vault deposit call — Trails replaces TRAILS_ROUTER_PLACEHOLDER_AMOUNT at execution
  const destinationCallData = encodeFunctionData({
    abi: erc4626Abi,
    functionName: 'deposit',
    args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, userAddress as `0x${string}`],
  })

  // 1. Quote — includes bridge + swap + vault deposit in one route
  const { intent, gasFeeOptions } = await trailsApi.quoteIntent({
    ownerAddress: userAddress,
    originChainId,
    originTokenAddress,
    originTokenAmount,
    destinationChainId: 137,            // Polygon
    destinationTokenAddress: depositTokenAddress,
    destinationToAddress: vaultAddress,
    destinationCallData,                 // capital D
    tradeType: TradeType.EXACT_INPUT,
    options: {
      slippageTolerance: 0.005,
    },
  })

  // 2. Commit — pass the full intent object; must execute within 10 minutes
  const { intentId } = await trailsApi.commitIntent({ intent })

  // 3. Execute — user signs the intent (gasless path)
  await trailsApi.executeIntent({
    intentId,
    depositSignature: {
      intentSignature: await signIntent(intent, walletClient), // EIP-712 sign
      selectedGasFeeOption: gasFeeOptions.feeOptions[0],
      userNonce: 1,
      deadline: Math.floor(Date.now() / 1000) + 3600,
    },
  })

  // Alternative: user submits deposit transaction manually
  // await trailsApi.executeIntent({ intentId, depositTransactionHash: '0x...' })

  // 4. Poll until bridge + vault deposit settles (can take 1-5 min)
  let done = false
  let intentReceipt
  while (!done) {
    ;({ intentReceipt, done } = await trailsApi.waitIntentReceipt({ intentId }))
  }

  if (intentReceipt.status === 'SUCCEEDED') {
    console.log('Vault deposit complete:', intentReceipt.destinationTransaction?.txnHash)
  } else {
    throw new Error(`Deposit failed: ${intentReceipt.originTransaction?.statusReason}`)
  }

  return intentReceipt
}

Note on signIntent: This is your wallet's EIP-712 signing function applied to the intent data. With viem, use signTypedData on the intent's structured data. Refer to the Trails execution docs for the exact typed data schema.

---

Calldata patterns

ERC-4626 standard

import { TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'
import { encodeFunctionData } from 'viem'

const calldata = encodeFunctionData({
  abi: [{
    name: 'deposit',
    type: 'function',
    inputs: [
      { name: 'assets', type: 'uint256' },
      { name: 'receiver', type: 'address' },
    ],
    outputs: [{ name: 'shares', type: 'uint256' }],
  }] as const,
  functionName: 'deposit',
  args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, receiverAddress],
})

Custom deposit(uint256) only

const calldata = encodeFunctionData({
  abi: [{
    name: 'deposit',
    type: 'function',
    inputs: [{ name: 'amount', type: 'uint256' }],
    outputs: [],
  }] as const,
  functionName: 'deposit',
  args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT],
})

Staking contract

const calldata = encodeFunctionData({
  abi: [{
    name: 'stake',
    type: 'function',
    inputs: [{ name: 'amount', type: 'uint256' }],
    outputs: [],
  }] as const,
  functionName: 'stake',
  args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT],
})

---

Direct API parameter reference

Parameter	Type	Description
ownerAddress	string	User's wallet address
originChainId	number	Source chain ID
originTokenAddress	string	Source token address
originTokenAmount	bigint	Amount in smallest unit
destinationChainId	number	137 for Polygon
destinationTokenAddress	string	Token the vault accepts
destinationToAddress	string	Vault contract address
destinationCallData	string	ABI-encoded vault call (capital D)
tradeType	TradeType	TradeType.EXACT_INPUT for all deposit flows

Safety checklist

1. Import TRAILS_ROUTER_PLACEHOLDER_AMOUNT — do not use a raw BigInt('0xff...') constant.
2. Verify the vault contract — confirm destinationToAddress / to.recipient is a trusted contract.
3. Check token decimals — USDC uses 6 decimals; WETH and POL use 18.
4. Test calldata encoding — decode with decodeFunctionData from viem before using in production.
5. Confirm vault accepts bridged token — some vaults accept native USDC (0x3c49...) only, not USDC.e (0x2791...).
6. Committed intents expire in 10 minutes — quote and execute promptly.

Common errors

Code	Cause	Fix
missing_api_key	API key not set	Check TRAILS_API_KEY or apiKey prop
quote_failed	No route to vault token	Confirm vault's deposit token is Trails-supported
quote_expired	>5 min since quote	Re-quote and commit immediately
intent_expired	>10 min since commit	Re-quote, re-commit, then execute
tx_reverted	Vault deposit call reverted	Verify ABI, token address, and placeholder usage
slippage_exceeded	Price moved beyond tolerance	Increase slippageTolerance or retry
unsupported_chain	Polygon not available	Call getChains() to verify