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The Vaults.fyi transaction API lets you integrate vault interactions — deposits, redemptions, and reward claims — across hundreds of protocols without writing any protocol-specific contract logic. You get back ready-to-sign transaction payloads that users submit directly to the protocol. No intermediary smart contracts sit between your users and their funds.

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Supported actions

The API supports the following vault interaction types:
ActionDescription
depositMove tokens into a vault to start earning yield
redeemWithdraw tokens from a vault in a single step (for instant-redeem vaults)
request-redeemSubmit a withdrawal request for vaults with a queue or delay
claim-redeemClaim tokens after a withdrawal request has been fulfilled
claim-rewardsCollect accrued reward tokens from a vault or across multiple vaults
Not all vaults support every action. Use the transaction context endpoint to check which actions are available for a specific vault and user before rendering UI controls.

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How transaction preparation works

1

Fetch transaction context

Call GET /v2/transactions/context/ with the vault address, network, and user wallet address. The response tells you which actions are available, the user’s current position and balances, and any claimable rewards.
2

Generate a transaction payload

Call GET /v2/transactions/{action}/ with the action you want to prepare (e.g., deposit), the vault, the amount, and the user address. The API returns a fully formed transaction payload — including calldata, to-address, and value — ready to be signed.
3

Present the transaction to the user

Pass the payload to your wallet integration (e.g., eth_sendTransaction for EOA wallets, or a UserOperation for ERC-4337 smart wallets). The user signs and submits directly to the protocol.
4

Confirm and update state

After the transaction is confirmed on-chain, re-fetch the transaction context or portfolio endpoints to reflect the updated position in your UI.

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EOA and smart wallet support

The API works with both externally owned accounts (EOA) and ERC-4337 compatible smart contract wallets.
For standard wallets (e.g., MetaMask, Coinbase Wallet), the API returns a single transaction object. Pass it directly to your wallet library and prompt the user to sign.The user’s transaction goes straight to the protocol contract — no proxy or intermediary contract is involved.

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Key properties

Non-custodial

Users transact directly with protocol smart contracts. Vaults.fyi never holds or controls user funds.

No extra contracts

The API prepares calldata for the protocol’s own contracts. No proxy or aggregator contracts are inserted.

Multi-vault rewards

The rewards endpoint discovers claimable rewards across all supported vaults for an address and generates batched claim payloads.

Monetization ready

Optionally embed a fee into transaction payloads to generate revenue when users transact through your integration.
Always call the transaction context endpoint before generating a payload. Attempting to prepare a transaction for an unsupported action or insufficient balance will return an error.

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API reference

See the full endpoint reference at /api/transactions, or explore the live spec at https://api.vaults.fyi/v2/documentation/.