> ## Documentation Index > Fetch the complete documentation index at: https://docs.8dx.io/llms.txt > Use this file to discover all available pages before exploring further. # Post api swap > POST building swap calldata for 8dx aggregation smart contract ## OpenAPI ````yaml /openapi.yaml post /api/{blockchain}/swap openapi: 3.1.0 info: title: swap-8dx description: '' license: name: '' version: 0.1.0 servers: - url: https://swap.ggp.gg - url: https://8dx.io security: [] tags: - name: swap description: Swap API endpoints - name: approve description: Approve (Permit) API endpoints - name: explorer description: Explorer API endpoints - name: order description: Limit Order API endpoints - name: healthcheck description: Health Check API endpoints paths: /api/{blockchain}/swap: post: tags: - swap description: POST building swap calldata for 8dx aggregation smart contract operationId: create_swap parameters: - name: blockchain in: path required: true schema: type: string enum: - ethereum - bsc - arbitrum requestBody: description: Params for building swap calldata content: application/json: schema: $ref: '#/components/schemas/SwapBody' required: true responses: '201': description: Built swap calldata for 8dx aggregation smart contract content: application/json: schema: $ref: '#/components/schemas/SwapResponse' '400': description: Bad request error from HTTP server content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: BadRequest: summary: Bad request value: code: 400 error: string '404': description: Not found error from HTTP server content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: NotFound: summary: Not found value: code: 404 error: string '408': description: Request timeout error from HTTP server content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: RequestTimeout: summary: Request timeout value: code: 408 error: string '500': description: Internal server error from HTTP server content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: Internal: summary: Internal value: code: 500 error: string components: schemas: SwapBody: type: object required: - path - dstAddress properties: apiKey: type: - string - 'null' deadline: type: - integer - 'null' format: int64 description: Deadline in seconds, default 3600 seconds (1 hour) minimum: 0 dstAddress: type: string description: Destination/taker wallet or contract fromAddress: type: - string - 'null' description: Source wallet or contract path: $ref: '#/components/schemas/InputPath' description: Quote path permit: oneOf: - type: 'null' - $ref: '#/components/schemas/PermitSwapBody' description: Permit2 data with EIP-2612 signature, if exist skipSimulation: type: - boolean - 'null' description: Whether to skip simulation slippageBps: type: - integer - 'null' format: int32 description: >- Custom slippage in bps, default using totalPriceImpact from the quote minimum: 0 usePermit: type: - boolean - 'null' description: Whether to use permit SwapResponse: type: object required: - data - to - value - minReturnAmountOut properties: computeUnits: type: - integer - 'null' format: int64 minimum: 0 data: type: string description: Calldata to send to the aggregator contract minReturnAmountOut: type: string to: type: string description: >- Aggregator contract address - recipient of the transaction (transaction `to`) tokenApprovalAddress: type: - string - 'null' description: >- Address that the user must approve for ERC20 spending (null for native-token swaps; equals `to` for non-permit ERC20 swaps; equals Permit2 address when `use_permit = true`) value: type: string description: Native value (msg.value) attached to the transaction, in wei ErrorResponse: type: object required: - error - code properties: code: type: integer format: int32 minimum: 0 error: type: string InputPath: allOf: - $ref: '#/components/schemas/InputOptimalRoute' - type: object required: - addressTokenIn - addressTokenOut - amountIn properties: addressTokenIn: type: string description: Source token contract address (ERC20 or native token) addressTokenOut: type: string description: Destination token contract address (ERC20 or native token) amountIn: type: string description: >- Amount of source token to swap (in token's smallest unit, e.g., wei for ETH) PermitSwapBody: type: object required: - data - signature properties: data: type: object signature: type: string InputOptimalRoute: type: object required: - steps - totalAmountOut - totalPriceImpact properties: steps: type: array items: type: array items: $ref: '#/components/schemas/InputPathStep' totalAmountOut: type: string description: >- Expected amount of destination token to receive (in token's smallest unit, e.g., wei for ETH) totalPriceImpact: type: integer format: int32 description: Price impact of the quote in bps minimum: 0 InputPathStep: allOf: - $ref: '#/components/schemas/Action' - type: object required: - tokenIn - tokenOut - percentBps properties: percentBps: type: integer format: int32 description: Percentage of the input allocated to this route in bps minimum: 0 tokenIn: type: string description: In step token contract address tokenOut: type: string description: Out of step token contract address Action: oneOf: - type: object required: - exchanger properties: exchanger: $ref: '#/components/schemas/ExchangerData' - type: object required: - wrap properties: wrap: $ref: '#/components/schemas/WrapData' ExchangerData: type: object required: - name - address - poolType - fee properties: address: type: string description: Pool contract address of the pool fee: type: integer format: int32 description: Fee of the pool in bps minimum: 0 name: type: string description: Name of the pool poolType: $ref: '#/components/schemas/PoolType' description: Type of the pool WrapData: type: object required: - isWrap - wrapperType - name properties: isWrap: type: boolean description: Whether the action is a wrap name: type: string description: Name of the wrap token wrapperType: $ref: '#/components/schemas/WrappedType' description: Type of the wrap token PoolType: type: string enum: - UniswapV2 - UniswapV3 - UniswapV4 - SushiSwapV2 - PancakeSwapV2 - PancakeSwapV3 - CurveStable - CurveCrypto - CurveNG - CurveMeta - BalancerV2 - BalancerV3 - FluidT1 - FluidLite WrappedType: type: string enum: - WETH - LidoWstETH - RocketPoolRETH - FraxSfrxETH - Custom ````