> ## Documentation Index > Fetch the complete documentation index at: https://developers.circle.com/llms.txt > Use this file to discover all available pages before exploring further. # Create a challenge for a wallet upgrade > Generates a challenge to create a transaction that upgrades a wallet. To identify the wallet, you must provide either `walletId`, or both `walletAddress` and `blockchain` in the request body. ## OpenAPI ````yaml openapi/user-controlled-wallets.yaml post /v1/w3s/user/transactions/walletUpgrade openapi: 3.0.3 info: version: '1.0' title: User-Controlled Wallets description: User-Controlled Wallets API documentation. servers: - url: https://api.circle.com security: - BearerAuth: [] tags: - name: Social/ Email Authentication - name: PIN Authentication - name: Users - name: Wallets - name: Transactions - name: Token Lookup - name: Signing paths: /v1/w3s/user/transactions/walletUpgrade: post: tags: - Transactions summary: Create a challenge for a wallet upgrade description: > Generates a challenge to create a transaction that upgrades a wallet. To identify the wallet, you must provide either `walletId`, or both `walletAddress` and `blockchain` in the request body. operationId: createUserTransactionWalletUpgradeChallenge parameters: - $ref: '#/components/parameters/XUserToken' - $ref: '#/components/parameters/XRequestId' requestBody: $ref: '#/components/requestBodies/CreateWalletUpgradeTransactionForEndUser' responses: '200': content: application/json: schema: $ref: >- #/components/schemas/CreateWalletUpgradeTransactionForEndUserResponse description: >- Returns the existing challenge if the idempotency key matches a previous successful request. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' '201': content: application/json: schema: $ref: >- #/components/schemas/CreateWalletUpgradeTransactionForEndUserResponse description: Successfully created the challenge for the wallet upgrade. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' '400': $ref: '#/components/responses/DefaultError' '401': $ref: '#/components/responses/NotAuthorized' '404': $ref: '#/components/responses/NotFound' security: - BearerAuth: [] components: parameters: XUserToken: name: X-User-Token description: Unique system generated JWT session token for specific user. required: true in: header schema: type: string XRequestId: name: X-Request-Id in: header description: > Developer-provided identifier for this request, used for tracing requests in Wallets API logs and the Developer Console, and when communicating with Circle Support. **Must be a UUID to appear in logs.** Non-UUID values are accepted by the API but are ignored by logging and tracing systems. schema: $ref: '#/components/schemas/XRequestId' requestBodies: CreateWalletUpgradeTransactionForEndUser: content: application/json: schema: title: CreateWalletUpgradeTransactionForEndUserRequest type: object required: - idempotencyKey - newScaCore properties: idempotencyKey: $ref: '#/components/schemas/IdempotencyKey' newScaCore: $ref: '#/components/schemas/NewScaCore' feeLevel: $ref: '#/components/schemas/FeeLevel' gasLimit: $ref: '#/components/schemas/GasLimit' gasPrice: $ref: '#/components/schemas/GasPrice' maxFee: $ref: '#/components/schemas/MaxFee' priorityFee: $ref: '#/components/schemas/PriorityFee' refId: $ref: '#/components/schemas/TransactionReferenceId' blockchain: $ref: '#/components/schemas/Blockchain' walletId: $ref: '#/components/schemas/WalletId' walletAddress: $ref: '#/components/schemas/Address' description: Creates a transaction for an end-user request. required: true schemas: CreateWalletUpgradeTransactionForEndUserResponse: title: CreateWalletUpgradeTransactionForEndUserResponse type: object properties: data: type: object required: - challengeId properties: challengeId: $ref: '#/components/schemas/ChallengeId' XRequestId: type: string format: uuid description: >- A unique identifier, which can be helpful for identifying a request when communicating with Circle support. example: 2adba88e-9d63-44bc-b975-9b6ae3440dde IdempotencyKey: type: string description: >- Universally unique identifier (UUID v4) idempotency key. This key is utilized to ensure exactly-once execution of mutating requests. To create a UUIDv4 go to [uuidgenerator.net](https://www.uuidgenerator.net). If the same key is reused, it will be treated as the same request and the original response will be returned. example: a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11 format: uuid NewScaCore: type: string description: >- `newScaCore` displays the version of the SCA available for upgrade. For a list of supported versions, refer to the developer documentation. enum: - circle_6900_singleowner_v2 example: circle_6900_singleowner_v2 FeeLevel: type: string enum: - LOW - MEDIUM - HIGH example: MEDIUM description: > A dynamic blockchain fee level setting (`LOW`, `MEDIUM`, or `HIGH`) that will be used to pay gas for the transaction. Calculated based on network traffic, supply of validators, and demand for transaction verification. Cannot be used with `gasPrice`, `priorityFee`, or `maxFee`. Estimates for each fee level can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. GasLimit: type: string description: > The maximum units of gas to use for the transaction. Required if `feeLevel` is not provided. Estimates for this limit can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. An insufficient gas limit may cause the transaction to fail on-chain. Use this field with care when manually providing values. GasLimit override (only supported for EOA wallets): Using `gasLimit` together with `feeLevel`, the provided `gasLimit` will override the estimation's gasLimit. example: '21000' GasPrice: type: string description: > For blockchains without EIP-1559 support, the maximum price of gas, in gwei, to use per each unit of gas (see `gasLimit`). Requires `gasLimit`. Cannot be used with `feeLevel`, `priorityFee`, or `maxFee`. Estimates for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. The wallet service enforces a dynamic minimum `gasPrice` based on current network conditions. Requests specifying a `gasPrice` below this minimum will be rejected MaxFee: type: string example: '5.935224468' description: > For blockchains with EIP-1559 support, the maximum price per unit of gas (see `gasLimit`), in gwei. Requires `priorityFee`, and `gasLimit` to be present. Cannot be used with `feeLevel` or `gasPrice`. Estimates for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. PriorityFee: type: string example: '1.022783914' description: > For blockchains with EIP-1559 support, the “tip”, in gwei, to add to the base fee as an incentive for validators. Please note that the `maxFee` and `gasLimit` parameters are required alongside the `priorityFee`. The `feeLevel` and `gasPrice` parameters cannot be used with the `priorityFee`. Estimations for this fee can be obtained through the [`POST /transactions/transfer/estimateFee`](/api-reference/w3s/developer-controlled-wallets/create-transfer-estimate-fee) API. The wallet service enforces a dynamic minimum `priorityFee` based on current network conditions. Requests specifying a `priorityFee` below this minimum will be rejected TransactionReferenceId: type: string example: grouptransaction123 description: Optional reference or description used to identify the transaction. Blockchain: type: string description: >- The blockchain network that the resource is to be created on or is currently on. enum: - ETH - ETH-SEPOLIA - AVAX - AVAX-FUJI - MATIC - MATIC-AMOY - SOL - SOL-DEVNET - ARB - ARB-SEPOLIA - NEAR - NEAR-TESTNET - EVM - EVM-TESTNET - UNI - UNI-SEPOLIA - BASE - BASE-SEPOLIA - OP - OP-SEPOLIA - APTOS - APTOS-TESTNET - ARC-TESTNET - MONAD - MONAD-TESTNET example: MATIC-AMOY WalletId: title: WalletId type: string format: uuid description: | Unique system generated identifier of the wallet. For contract deploys this wallet ID will be used as the source. example: a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11 Address: title: Address description: > Blockchain generated unique identifier, associated with wallet (account), smart contract or other blockchain objects. type: string example: '0xca9142d0b9804ef5e239d3bc1c7aa0d1c74e7350' ChallengeId: type: string format: uuid description: >- Unique system generated identifier used to initiate a user challenge flow. example: c4d1da72-111e-4d52-bdbf-2e74a2d803d5 Error: title: Error type: object required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. headers: XRequestId: description: > Developer-provided header parameter or Circle-generated universally unique identifier (UUID v4). Useful for identifying a specific request when communicating with Circle Support. schema: $ref: '#/components/schemas/XRequestId' responses: DefaultError: content: application/json: schema: $ref: '#/components/schemas/Error' description: Error response headers: X-Request-Id: $ref: '#/components/headers/XRequestId' NotAuthorized: content: application/json: schema: type: object title: NotAuthorizedResponse required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. example: code: 401 message: Malformed authorization. description: >- Request has not been applied because it lacks valid authentication credentials. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' NotFound: content: application/json: schema: type: object title: NotFoundResponse required: - code - message properties: code: type: integer description: Code that corresponds to the error. message: type: string description: Message that describes the error. example: code: 404 message: Not found. description: Specified resource was not found. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' securitySchemes: BearerAuth: type: http scheme: bearer bearerFormat: PREFIX:ID:SECRET description: >- Circle's API Keys are formatted in the following structure "PREFIX:ID:SECRET". All three parts are required to make a successful request. ````