Discover and pay
The OpenAPI document publishes methods, inputs and indicative prices. The agent catalog, x402 discovery, token registry and supported protocols are free reads. For licensed equity data (vendor-resolved tickers; no market-coverage claim), read each route’s vendor, available fields and coverage limits in the agent catalog before paying. API & agent coverage compares the interfaces; it does not establish coverage for a particular ticker.402 with its PAYMENT-REQUIRED challenge. Use an OKX-compatible x402 signer to select the advertised token and scheme, sign, then retry the same request with PAYMENT-SIGNATURE. The service advertises USDT0, USDC and USDG options; read the token address, amount, network and EIP-712 domain from the chosen option. Do not assume accepts[0] is USDC. exact and aggr_deferred are distinct payment schemes; use only one supported by your client.
Service fees settle on X Layer even when an execution action uses another chain. The fee does not fund the principal you invest or trade. API schemas and examples shows how to inspect each request without paying.
Choose an operation
This is a task index; the linked OpenAPI contains the complete body schemas. Most execution amounts are human-readable decimal strings.
principalAuth.value and Yield Watch’s maxPrincipalRaw use atomic token units. Slippage units differ by route: inspect the schema rather than reusing a swap percentage on a DeFi request.
Sub-wallet custody and funding
Otto X sub-wallets are TEE-custodial. Keys are held in OKX’s Trusted Execution Environment and Otto’s operator credential authorizes signing. You do not receive a seed phrase or directly control the execution key. This account is separate from the Otto app’s connected wallet, Coinbase account and legacy Safe accounts.GET /sub-wallet is a paid resolve-or-provision call bound to the verified x402 payer. An address query cannot select another payer. GET /sub-wallet/preview?address=0x... is a free lookup that never provisions; use its returned sub_wallet.evm_address and verify it before funding.
Fund with a signed authorization
Where supported, include an EIP-3009principalAuth alongside the separate x402 fee. The principal travels from your payment wallet directly into its sub-wallet on the action’s chain. Supported principal tokens are USDC on Base, Arbitrum, Optimism, Ethereum and Polygon, and USDT0 on X Layer.
Example /auto-swap body shape; replace the addresses, future expiry, nonce and signature with your own signed values:
validBefore: 0 is a placeholder and must be replaced with a future Unix timestamp before signing. The sender must equal the verified payer; the recipient must equal its sub-wallet. The authorization is time-limited and nonce-protected. For auto-swap, auto-bridge and auto-defi-invest, value must cover the operation amount. Yield Copilot requires amount when principalAuth is present and an exactly equal atomic value.
Fund after a balance request
Without sufficient sub-wallet principal, a supported operation can return409 FUNDS_REQUIRED, with a deposit address, chain, token, required amount and idempotency_key. That response does not settle the x402 service fee. Check those details, deposit the requested principal, then retry the original intent with the returned idempotency-key header. Its retry window is up to seven days; the service also deduplicates identical payer/operation/body requests.
Preserve returned transaction hashes and operation identifiers. A timeout after funding or broadcast is not proof that no funds moved; reconcile the original operation before creating another.
Yield deposits and withdrawals
Yield Copilot chooses among the allowlisted lending venues for the requested stablecoin on Base, Arbitrum, Optimism, Ethereum or X Layer. Omitamount only if you intend to deploy the full idle balance. APY sources and missing values appear in the result; an unavailable comparison can return APY_DATA_UNAVAILABLE instead of guessing. X Layer may return apy: null. Ethereum execution can be declined during a base-fee spike.
The result includes the selected venue, before/after balances, APY source, fee economics and transaction hashes. A quoted APY is variable and projected yield is not realized profit. Read /supported-protocols for current protocol × chain × token combinations; Lido’s ETH staking is distinct from stablecoin lending.
GET /yield-farming-active returns current positions and rates; its rebalance suggestions do not execute a move. GET /yield-farming-historical returns recorded operations, fees and attributable realized results. A null realized value with a reason means attribution is incomplete, including some partial or externally funded positions.
To exit:
- Revoke any active Yield Watch policy as described below and confirm its paused/revoked state.
- Redeem the position with
POST /auto-defi-withdraw, for example{"protocol":"aave_v3","chain":"base","token":"USDC","ratio":"1"}for a full position. Wait for confirmation and check the sub-wallet balance. - Transfer the resulting balance with
POST /auto-withdraw, supplyingchain, token contract (or"native"), human-readableamountand yourtoAddress. Repeat for other tokens or chains as needed.
Yield Watch
POST /yield-watch registers notify or auto mode. Notify sends Telegram alerts without trading. Auto grants a signed permission for at most 30 days to rebalance between Aave V3 and Compound V3; Morpho is not accepted in auto mode. Read the current schema for supported chains, tokens and policy floors.
The signed policy binds wallet, sub-wallet, scope, expiry and nonce. maxMoves caps the number of moves; positive maxPrincipalRaw caps live position size per move. "0" means no principal cap. Hysteresis, minimum hold, throttle, fresh APY data, TVL checks and confirmed transaction receipts constrain execution. They do not guarantee returns or prevent market loss. Registering a policy is not evidence that a rebalance completed.
Use paid GET /yield-watch for state and GET /yield-watch/audit?limit=50 for events and transaction hashes. Read failed phases to determine whether capital remains in the old venue or idle in the sub-wallet. Bookkeeping calls currently cost $0.001; execution legs carry their own fees. Check each challenge.
Revoke with DELETE /yield-watch: both modes require the verified payer and a signed YieldWatchRevocation body. Use the current next nonce from the status response. Confirm the returned mode, paused and advanced nonce. A stale signature cannot revoke or reactivate a later policy.
Exact Yield Watch signing contract
Exact Yield Watch signing contract
Use EIP-712 typed data, with domain:This is an off-chain authority domain; its chain ID is not the execution chain. Registration’s primary type is
YieldWatchDelegation, with fields in this order:Arrays must be sorted and unique. POST the signed
message and signature with mode: "auto" and telegramChatId. Notify registration uses the schema’s flat fields and verified payer, without a delegation signature.Revocation’s primary type is YieldWatchRevocation, with ordered fields wallet: address, subWallet: address, nonce: uint256, issuedAt: uint256. DELETE its { "message": {...}, "signature": "0x..." } body while paying from that same wallet. Use a fresh Unix issuedAt. A registration signature is not a revocation signature. The verifier uses EIP-712 even if a discovery description calls the signature EIP-191.Research recipes
Recipes combine several data sources into one result and one payment. Use the free recipe index for current inputs and prices:
A missing core result causes a recipe error without settling the service fee. Unavailable best-effort sources are identified in the result. A token screen is evidence to inspect, not a safety guarantee or instruction to trade.