Swap & Bridge Integration

Use TaskType.GetTokenOut for cross-chain swaps and bridges where the user receives a target token on a destination chain.

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When to use each pattern

User goal	Task type	Amount pattern
Swap token A → token B on another chain	GetTokenOut	Forward quote: set tokenInAmount
Bridge same asset to another chain	GetTokenOut	Forward quote: set tokenInAmount
Receive exact output (e.g. pay exactly 50 USDC on Base)	GetTokenOut or ProtocolInteraction	Reverse quote: tokenInAmount: "0", set minTokenOut

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Forward quote

User specifies how much they want to spend:

const { taskTypeString, intentData } = await sdk.getTaskData({
  taskType: TaskType.GetTokenOut,
  intentData: {
    isNative: false,
    depositTokenAddress: SOURCE_USDC,
    tokenInAmount: parseUnits("100", 6).toString(),  // user spends 100 USDC
    outputTokenAddress: DEST_USDC,
    minTokenOut: "0",                               // accept any output >= 0
    destinationChainId: "8453",
    protocolHashIdentifier: "0x0000000000000000000000000000000000000000000000000000000000000000",
    recipient: sponsorAddress,
  },
  extraDataTypestring: "",
  extraData: {},
});

Display quote.tokenOut to the user as the expected receive amount.

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Reverse quote

User needs an exact output; Epoch computes the required input:

const { taskTypeString, intentData } = await sdk.getTaskData({
  taskType: TaskType.GetTokenOut,
  intentData: {
    isNative: false,
    depositTokenAddress: SOURCE_USDC,
    tokenInAmount: "0",                             // backend computes input
    outputTokenAddress: DEST_TOKEN,
    minTokenOut: parseUnits("50", 6).toString(),    // user must receive exactly 50
    destinationChainId: "8453",
    protocolHashIdentifier: "0x0000000000000000000000000000000000000000000000000000000000000000",
    recipient: sponsorAddress,
  },
  extraDataTypestring: "",
  extraData: {},
});

const quote = await sdk.getIntentQuote({ sponsorAddress, taskTypeString, intentData, isNative: false });
// Display quote.tokenIn as "You will pay approximately X USDC"

Reverse quotes are required for fixed-price purchases (raffle tickets, exact payment amounts).

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Approvals

Before or during solveIntent, the user may need to approve the input token on the source chain. The SDK returns approval transactions when needed.

Your UI should:

1. Detect when approval is required (from quote or solve response).

2. Prompt the user to sign the approval transaction.

3. Proceed to the main intent solve after approval confirms.

Ensure the wallet is on the source chain before signing.

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Displaying quotes

Show the user:

Field	Label suggestion
quote.tokenIn	"You pay"
quote.tokenInSymbol	Token symbol
quote.tokenOut	"You receive"
quote.path	Optional: "Route" (human-readable summary)
Slippage / fees	If exposed in quote response

Always require explicit user confirmation before calling solveIntent.

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Routing & liquidity options

Optional routingAndLiquidityOptions lets integrators choose how the swap is filled:

Preset	When to use
any	Default — best quote across all solvers
filler-single-transaction	Prefer Epoch filler liquidity — the user signs one transaction for seamless end-to-end execution (protocol interactions are handled behind the scenes)
external-multi-transactions	External aggregators only (multi-step signing)
custom	Pin specific solver address(es)

Pass the same options to getIntentQuote and solveIntent:

const routingAndLiquidityOptions = { preset: "filler-single-transaction" as const };

const quote = await sdk.getIntentQuote({
  sponsorAddress,
  taskTypeString,
  intentData,
  routingAndLiquidityOptions,
});

await sdk.solveIntent({ ...params, quoteResult: quote, routingAndLiquidityOptions });

See SDK Reference.

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Chain and token selection

• Source chain: where the user's wallet is connected and input tokens exist.

• Destination chain: where output tokens are delivered (destinationChainId).

• Use token addresses from Chains & Tokens.

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Resource locks

If quote.resourceLockRequired === true, the intent requires Compact collateral. See Core Concepts and contact Epoch for Compact partner setup.

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Next steps

• Protocol Interaction — combine swap/bridge with on-chain actions

• Error Handling