> ## Documentation Index > Fetch the complete documentation index at: https://docs.walletsuite.io/llms.txt > Use this file to discover all available pages before exploring further. # Prepare transfer signing payload > Prepares signing payload for TRANSFER_NATIVE or TRANSFER_TOKEN, calculates nonce (EVM), calldata (EVM ERC20), fee params, and runs a simulation check. Amount can be specified in two ways (mutually exclusive): - `amountWei` - raw amount in smallest units (wei / sun) - `amount` - human-readable amount (e.g. "1.5" for 1.5 ETH); backend resolves decimals automatically When using `amount`, decimals are resolved from the chain (native transfers) or from the asset registry for the provided `tokenContract` (token transfers). For `TRANSFER_TOKEN`, `tokenContract` is required. `symbol` is optional and only acts as an auxiliary decimal hint after the token is identified by `tokenContract`. Returns 400 if decimals cannot be resolved. ## OpenAPI ````yaml /openapi.json post /api/txs/prepare-sign openapi: 3.1.0 info: title: WalletSuite REST API description: >- Multi-chain wallet operations, balances, prices, and transaction lifecycle as a REST API. contact: name: WalletSuite url: https://walletsuite.io version: prod servers: - url: https://api.walletsuite.io description: WalletSuite API security: - ApiKeyAuth: [] tags: - name: Transactions description: >- Get transaction history by address, check live transaction status, and send signed transactions. - name: Fees description: Fee estimation endpoints - name: Balances description: Fetch balances on any supported chain (Ethereum, Tron). - name: Assets description: >- List supported blockchain assets from the database loaded at startup from bundled resources - name: Asset Status description: Asset enablement and restrictions. - name: Prices description: Fiat prices for symbols and contract addresses - name: Swaps description: Swap quote, route, and transaction building. - name: Approvals description: Allowance, approval tx data, and approval status. - name: NFTs description: NFT collections, tokens, owners, and transfer building. - name: Staking description: Native staking APR, validators, positions, and transaction building. - name: Name Service description: Name resolution and reverse resolution. - name: Chains description: Chain registry and chain capabilities. - name: Chain Specific description: Chain specific endpoints consumable by SDK. - name: Blocks description: View most recently indexed block information. - name: Info description: General information and summary counts. paths: /api/txs/prepare-sign: post: tags: - Transactions summary: Prepare transfer signing payload description: >- Prepares signing payload for TRANSFER_NATIVE or TRANSFER_TOKEN, calculates nonce (EVM), calldata (EVM ERC20), fee params, and runs a simulation check. Amount can be specified in two ways (mutually exclusive): - `amountWei` - raw amount in smallest units (wei / sun) - `amount` - human-readable amount (e.g. "1.5" for 1.5 ETH); backend resolves decimals automatically When using `amount`, decimals are resolved from the chain (native transfers) or from the asset registry for the provided `tokenContract` (token transfers). For `TRANSFER_TOKEN`, `tokenContract` is required. `symbol` is optional and only acts as an auxiliary decimal hint after the token is identified by `tokenContract`. Returns 400 if decimals cannot be resolved. operationId: prepareSign requestBody: content: application/json: schema: $ref: '#/components/schemas/PrepareSignRequestDto' required: true responses: '200': description: OK content: '*/*': schema: $ref: '#/components/schemas/ApiResponsePrepareSignResponseDto' components: schemas: PrepareSignRequestDto: type: object properties: chain: type: string from: type: string to: type: string amountWei: type: integer amount: type: string symbol: type: string txType: type: string enum: - TRANSFER_NATIVE - TRANSFER_TOKEN - CONTRACT_CREATION - CONTRACT_CALL - SWAP - STAKE - UNSTAKE - CLAIM_REWARDS - UNKNOWN tokenContract: type: string nonce: type: integer maxPriorityFeePerGasWei: type: integer priorityFeeMultiplier: type: number format: double required: - chain - from - to - txType ApiResponsePrepareSignResponseDto: type: object properties: ok: type: boolean code: type: string message: type: string data: $ref: '#/components/schemas/PrepareSignResponseDto' required: - code - message - ok PrepareSignResponseDto: type: object properties: chain: type: string chainId: type: integer format: int64 from: type: string to: type: string valueWei: type: integer data: type: string txType: type: string enum: - TRANSFER_NATIVE - TRANSFER_TOKEN - CONTRACT_CREATION - CONTRACT_CALL - SWAP - STAKE - UNSTAKE - CLAIM_REWARDS - UNKNOWN tokenContract: type: string nonce: type: integer fee: $ref: '#/components/schemas/FeeParamsDto' required: - chain - fee - from - to - txType - valueWei FeeParamsDto: type: object properties: mode: type: string enum: - EIP1559 - LEGACY - TRON gasLimit: type: integer baseFeePerGas: type: integer maxPriorityFeePerGas: type: integer maxFeePerGas: type: integer gasPrice: type: integer el: type: integer rp: $ref: '#/components/schemas/TronBlockHeaderDto' sol: $ref: '#/components/schemas/SolanaFeeDetailsDto' required: - mode TronBlockHeaderDto: type: object properties: h: type: string 'n': type: integer format: int64 t: type: integer format: int64 p: type: string r: type: string w: type: string v: type: integer format: int32 required: - h - 'n' - t - v SolanaFeeDetailsDto: type: object properties: bh: type: string lvbh: type: integer format: int64 ns: type: integer format: int32 bf: type: integer format: int64 cu: type: integer format: int64 cup: type: integer format: int64 pf: type: integer format: int64 tf: type: integer format: int64 msg: type: string signers: type: array items: type: string required: - bf - bh - cu - cup - lvbh - msg - ns - pf - signers - tf securitySchemes: ApiKeyAuth: type: apiKey description: API key provided by WalletSuite team name: x-api-key in: header ````