Intents¶

TAO Intents lets your users move value between chains. The user says what they want, for example "100 USDC on Ethereum in, TAO on Subtensor EVM out", and signs two transactions on the origin chain: an approval for USDC, then the order itself, which locks the input in the Intents contract. A solver then delivers the output to the recipient on the destination chain. If nobody fills the intent before its deadline, the input is refunded, always in USDC, on the origin chain.

Recommended: use the SDK¶

The TypeScript SDK is the easiest way to integrate. One call gets a quote, approves USDC, opens the intent, and gives you an order to track:

import { TaoIntents } from "@tao.com/intents-sdk";

const intents = new TaoIntents({ rpcUrls: { 1: "https://YOUR-ETHEREUM-RPC" } });

const { order, quote } = await intents.execute({
  wallet: window.ethereum,
  originChainId: 1,
  destinationChainId: 964,
  outputToken: "TAO",
  amount: "100", // 100 USDC
});

const result = await order.waitForSettlement(); // "filled" | "refunded"

See the SDK guide for installation, progress events, quotes, order tracking, and error handling.

Under the hood¶

The SDK uses two pieces, and you can also call them directly if you can't use the SDK:

The Quoter API tells you how much the user will receive for a given input.
The Intents smart contract is where you submit the intent. Your app calls it directly from the user's wallet. No TAO API sits between your users and the contract.

How it works¶

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sequenceDiagram
    autonumber
    participant App as Your app
    participant Quoter as Quoter API
    participant Origin as Intents contract<br/>(origin chain)
    participant Solver
    participant Dest as Intents contract<br/>(destination chain)

    App->>Quoter: Request a quote
    Quoter-->>App: Output amount
    App->>Origin: approve USDC, then open(order)
    Note over App,Origin: USDC is escrowed
    Origin-->>Solver: Open event
    alt Filled before fillDeadline
        Solver->>Dest: fill(order)
        Dest->>App: Output delivered to the recipient
    else Not filled before fillDeadline
        Origin-->>App: Refunded event
        Note over App,Origin: Input returned to the user, in USDC, on the origin chain
    end

Quote. Call the Quoter API with the route and amount. It returns the output amount a solver is willing to deliver.
Open. Have the user approve USDC and call open on the Intents contract, passing the quoted output amount. The contract escrows the USDC and emits an Open event with the order ID.
Fill. A solver sees the event and sends the output token to the recipient on the destination chain.
Refund. If the intent is not filled before its fillDeadline, the protocol refunds the escrowed USDC to the user on the origin chain. The refund is sent after the deadline passes, the user cannot trigger it, and the order stays pending until the Refunded event. See order status to tell a refund from an order that is still waiting.

The SDK follows these steps for you. The contract is the source of truth: you can also follow an order using contract events and reads alone.

Start here¶

Page	Use for
SDK (recommended)	Install the TypeScript SDK and open an intent with one call.
Integration Guide	Integrating without the SDK: a complete example that calls the Quoter API and the contract directly.
Quoter API	Request and response details, deadlines, and error handling for quotes.
Smart Contract	Contract addresses, the `open` function, the order struct, events, refunds, and reverts.
Quoter API Reference	The OpenAPI reference for the quote endpoint.

Supported routes¶

These are the mainnet deployments. Intents are opened on an origin chain and filled on a different destination chain.

Chain	Chain ID	Intents contract	USDC (input token)
Ethereum	`1`	`0x2831Ea5524f171735aF8FEB2e331821bef176C8A`	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48`
Subtensor EVM	`964`	`0x24834012973b6e70997a23C7aAB01481d46CB8E1`	`0x9001dbe4D68d36ab87923A2a9Dfb0c745fd25001`

Tokens¶

Chain	Token	Address	Decimals	Use
Ethereum	USDC	`0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48`	6	Input and output
Ethereum	ETH (native)	`0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE`	18	Output
Subtensor EVM	USDC (on-chain symbol `USDC.e`)	`0x9001dbe4D68d36ab87923A2a9Dfb0c745fd25001`	6	Input and output
Subtensor EVM	wTAO	`0x134f59E8B8637FD70ae12f263492B1dc73A25D1e`	18	Output
Subtensor EVM	TAO (native)	`0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE`	18	Output

The USDC on Subtensor EVM is a bridged token whose on-chain symbol is USDC.e, so wallets label it USDC.e. These docs call it USDC. The native-token address is a placeholder that the contract and the Quoter API use for ETH and TAO.

Input: USDC on the origin chain.
Output: any token in the table for the destination chain.
Recipient: an EVM (0x) address on the destination chain. Native TAO on Subtensor can also be delivered to a Substrate account through the SDK, and subnet alpha can be staked to a Substrate coldkey (Deliver subnet alpha).

If a pair is not supported, the Quoter API returns an error instead of a quote.

Fees¶

The Intents contract charges a protocol fee, currently 0.30% (30 basis points), taken from the USDC the user pays. The quote already accounts for it, and you cap it in the order with maxProtocolFeeBps. Solver costs are reflected in the quoted output amount, so there is nothing else to add on top of the quote.

Authentication¶

Neither the SDK, the Quoter API, nor the smart contract needs an API key or access token.