> ## Documentation Index > Fetch the complete documentation index at: https://digraphsas-docs-cli.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # Build Market swap transaction > Build calldata for an Augustus v6.2 swap from a Market priceRoute. ## OpenAPI ````yaml api-reference/specs/market.json POST /transactions/{chainId} openapi: 3.0.3 info: title: Velora Market API version: 1.0.0 description: Velora Market API — direct aggregator pricing and Augustus calldata. servers: - url: https://api.velora.xyz description: Production security: [] externalDocs: description: Market — how it works (prices → calldata → broadcast). url: https://velora.xyz/docs/market/how-it-works paths: /transactions/{chainId}: post: summary: Build calldata for a Market Swap description: >- Build ready-to-broadcast transaction parameters from the `priceRoute` returned by GET /prices, passed verbatim. Unless `ignoreChecks=true`, the API verifies balances and allowances and simulates the transaction before returning calldata, so the response includes a `gas` estimate. operationId: marketTransactions parameters: - name: chainId in: path required: true schema: $ref: '#/components/schemas/ChainId' description: EVM chain ID. Matches `priceRoute.network`. - name: gasPrice in: query required: false schema: type: string description: Gas price to use for the transaction, in WEI. - name: ignoreChecks in: query required: false schema: type: boolean default: false description: >- Skip on-chain balance, allowance, and transaction-failure checks. The response omits the `gas` field when enabled. - name: ignoreGasEstimate in: query required: false schema: type: boolean default: false description: >- Skip the gas estimate. The response omits the `gas` field when enabled. - name: onlyParams in: query required: false schema: type: boolean default: false description: >- Return only the contract call parameters instead of a full transaction object. - name: eip1559 in: query required: false schema: type: boolean default: false description: >- Return an EIP-1559 transaction with `maxFeePerGas` and `maxPriorityFeePerGas` in place of `gasPrice`. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/MarketTransactionRequest' responses: '200': description: Augustus calldata + tx fields. content: application/json: schema: $ref: '#/components/schemas/MarketTransactionResponse' '400': description: >- Invalid input or stale priceRoute. Documented examples: `InvalidInput`, `StalePriceRoute`. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '500': description: Internal server error. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' components: schemas: ChainId: type: integer description: >- EVM chain ID. Supported values today include 1 (Mainnet), 10 (Optimism), 56 (BSC), 137 (Polygon), 8453 (Base), 42161 (Arbitrum), 43114 (Avalanche), 100 (Gnosis). The set is open — call GET /chains for the live list. example: 1 MarketTransactionRequest: type: object required: - srcToken - destToken - priceRoute - userAddress properties: priceRoute: allOf: - $ref: '#/components/schemas/MarketPriceRoute' description: >- The `priceRoute` block returned by GET /prices, passed verbatim — do not recompute or re-encode. srcToken: allOf: - $ref: '#/components/schemas/Address' description: >- Source token address. A token symbol listed in /tokens can be used instead. srcDecimals: type: integer description: >- Source token decimals. Can be omitted if a token symbol is used in srcToken. destToken: allOf: - $ref: '#/components/schemas/Address' description: >- Destination token address. A token symbol listed in /tokens can be used instead. destDecimals: type: integer description: >- Destination token decimals. Can be omitted if a token symbol is used in destToken. srcAmount: allOf: - $ref: '#/components/schemas/TokenAmount' description: >- Source amount in WEI/raw units. Required when `side=SELL`. On `side=BUY` it can be omitted if `slippage` is provided. destAmount: allOf: - $ref: '#/components/schemas/TokenAmount' description: >- Destination amount in WEI/raw units. Required when `side=BUY`. On `side=SELL` it can be omitted if `slippage` is provided. slippage: type: integer minimum: 0 maximum: 10000 description: >- Allowed slippage in basis points (0–10000). `250` = 2.5%. Required when the non-fixed amount (destAmount on SELL, srcAmount on BUY) is omitted. userAddress: allOf: - $ref: '#/components/schemas/Address' description: >- Address of the transaction caller (msg.sender). When using an intermediary contract, userAddress should correspond to msg.sender and receiver to the recipient. txOrigin: allOf: - $ref: '#/components/schemas/Address' description: >- When msg.sender differs from the transaction sender, pass the sender here along with userAddress. receiver: allOf: - $ref: '#/components/schemas/Address' description: >- Recipient of the swap output, for Swap & Transfer. Omit when userAddress receives. partner: type: string example: my-app-name description: >- Partner string. Used for analytics and fee attribution on your project's swaps. partnerAddress: allOf: - $ref: '#/components/schemas/Address' description: Address entitled to claim partner fees or surplus. partnerFeeBps: type: string description: Partner fee in basis points, used with partnerAddress. `200` = 2%. permit: type: string description: >- Signed permit payload (hex). Lets the swap skip the separate approve transaction. deadline: type: integer description: >- Unix timestamp (seconds) after which the transaction is no longer valid. isCapSurplus: type: boolean default: true description: Cap collected surplus at 1%. takeSurplus: type: boolean default: false description: Collect positive slippage as surplus. Works with partnerAddress. isSurplusToUser: type: boolean default: false description: >- Route positive slippage / surplus to the user instead of the partner. isDirectFeeTransfer: type: boolean default: false description: >- Transfer the partner fee directly rather than accruing it in the Fee Vault. MarketTransactionResponse: type: object description: Augustus calldata + tx envelope ready to broadcast. properties: from: allOf: - $ref: '#/components/schemas/Address' description: End-user wallet address (the `userAddress` from the request). to: allOf: - $ref: '#/components/schemas/Address' description: >- The Augustus v6.2 router. Send the transaction here; it is also the ERC-20 spender to approve. value: type: string example: '0' description: >- Native token amount in WEI to send with the transaction. `"0"` for ERC-20 sources. data: type: string description: Encoded swap calldata. gasPrice: type: string example: '16000000000' description: >- Suggested gas price in WEI. Replaced by maxFeePerGas / maxPriorityFeePerGas when `eip1559=true`. maxFeePerGas: type: string description: EIP-1559 max fee per gas in WEI. Present when `eip1559=true`. maxPriorityFeePerGas: type: string description: >- EIP-1559 max priority fee per gas in WEI. Present when `eip1559=true`. gas: type: string description: >- Gas limit estimate from the API's transaction checks. Returned by POST /transactions unless `ignoreChecks` or `ignoreGasEstimate` is set; omitted by GET /swap, where you estimate locally before broadcasting. chainId: $ref: '#/components/schemas/ChainId' ErrorResponse: type: object description: Standard Velora error envelope. required: - errorType properties: errorType: $ref: '#/components/schemas/ErrorCode' details: type: string description: Human-readable description of the failure. example: errorType: PricingError details: Error getting price data MarketPriceRoute: type: object description: >- Market route block. Calldata-ready against Augustus v6.2 when `version=6.2`. properties: blockNumber: type: integer network: $ref: '#/components/schemas/ChainId' srcToken: $ref: '#/components/schemas/Address' srcDecimals: type: integer srcAmount: $ref: '#/components/schemas/TokenAmount' destToken: $ref: '#/components/schemas/Address' destDecimals: type: integer destAmount: $ref: '#/components/schemas/TokenAmount' bestRoute: type: array items: type: object gasCostUSD: type: string gasCost: type: string side: type: string enum: - SELL - BUY version: type: string contractAddress: $ref: '#/components/schemas/Address' tokenTransferProxy: $ref: '#/components/schemas/Address' contractMethod: type: string partnerFee: type: number srcUSD: type: string destUSD: type: string partner: type: string maxImpactReached: type: boolean hmac: type: string Address: type: string description: >- EVM address (20 bytes, hex-encoded with `0x` prefix). Use the mixed-case placeholder `0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE` for native ETH. pattern: ^0x[a-fA-F0-9]{40}$ example: '0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045' TokenAmount: type: string description: >- Token amount in WEI / raw units (no decimal point). Serialized as a string to preserve precision for amounts that exceed JavaScript Number range. example: '1000000000000000000' ErrorCode: type: string description: >- Documented Velora error code (e.g. `PricingError`, `InvalidInput`, `UnsupportedChain`, `StalePriceRoute`, `InvalidSignature`). The set is open — handle codes you recognize and fall back to a generic error path for everything else. See /api-reference/troubleshooting for known codes. example: PricingError ````