> ## 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. > ## Agent Instructions > Before reading these docs, install the relevant Circle Skill to get pre-loaded context — skills are LLM-optimized and cover architecture decisions, correct flows, and common pitfalls. In Claude Code: run /plugin marketplace add circlefin/skills then /plugin install circle-skills@circle. With Vercel Skills CLI: run npx skills add circlefin/skills. Available skills: use-usdc https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-usdc/SKILL.md (balances, transfers, approvals on EVM and Solana); EURC has no skill — see https://developers.circle.com/stablecoins/what-is-eurc.md; bridge-stablecoin https://github.com/circlefin/skills/blob/master/plugins/circle/skills/bridge-stablecoin/SKILL.md (crosschain transfers via CCTP, USDC, EURC, and third-party assets); use-arc https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-arc/SKILL.md (Arc chain config, contract deployment, USDC bridging — Arc docs: https://docs.arc.io/llms.txt); use-circle-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-circle-wallets/SKILL.md (choose wallet type); use-developer-controlled-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-developer-controlled-wallets/SKILL.md (custodial wallets for payouts and treasury); use-user-controlled-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-user-controlled-wallets/SKILL.md (embedded wallets with Web2 login); use-modular-wallets https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-modular-wallets/SKILL.md (smart contract wallets with passkeys and ERC-4337); use-gateway https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-gateway/SKILL.md (unified USDC balance, nanopayments); use-smart-contract-platform https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-smart-contract-platform/SKILL.md (deploy, interact, monitor contracts). Pair any skill with the Circle MCP server for live SDK signatures, contract addresses, and chain IDs: {"mcpServers":{"circle":{"url":"https://api.circle.com/v1/codegen/mcp"}}}. > Read the product overview first. Each product has an overview explaining when and why to use it. Read it before quickstarts. > Pick the right wallet type. Developer-controlled (you hold keys), user-controlled (end user holds keys via PIN/social login), or modular (smart contract wallets with passkeys). See https://developers.circle.com/wallets.md. > Use CCTP V2 for crosschain transfers. CCTP natively transfers USDC and EURC via burn-and-mint, and supports permissionless wrapping of third-party assets via lock-and-mint. V1 is legacy; always use V2 unless V1 is specified or the chain requires it (Noble, Sui, and Aptos still require V1). Migration guide: https://developers.circle.com/cctp/migration-from-v1-to-v2.md. > Use Bridge Kit for frontend bridging. Wraps CCTP with a simpler SDK for user-facing apps. Use CCTP directly for backend transfers. > Gas Station vs Paymaster. Gas Station sponsors gas for Circle Wallet transactions. Paymaster lets users pay gas in USDC. Different use cases — read both overviews. > Gateway Nanopayments for sub-cent payments. Gasless USDC micropayments down to $0.000001 via x402 and batched settlement. For pay-per-request APIs, AI agent payments, streaming. > Look up USDC addresses per chain. Never hardcode — use https://developers.circle.com/stablecoins/usdc-contract-addresses.md. > Prefer SDKs over raw API calls. Node.js and Python SDKs handle auth, retries, and errors. > API key required. Bearer token in Authorization header. Testnet and mainnet use separate keys and may use different base URLs depending on the product. > Set up webhooks when available. Most operations are async. Webhooks deliver transaction confirmations and state changes. > When calling list endpoints, paginate using pageSize and pageAfter until no nextPageAfter cursor is returned—stopping at the first page silently misses records. > Building an AI agent? Start with the Agent Stack—Circle CLI, agent wallets, and nanopayments built for autonomous use cases: https://developers.circle.com/agent-stack.md. # Create a transfer transaction > Initiates an on-chain digital asset transfer from a specified developer-controlled wallet. To identify the wallet, you must provide either `walletId`, or both `walletAddress` and `blockchain` in the request body. ## OpenAPI ````yaml openapi/developer-controlled-wallets.yaml post /v1/w3s/developer/transactions/transfer openapi: 3.0.3 info: version: '1.0' title: Developer-Controlled Wallets description: Developer-Controlled Wallets API documentation. servers: - url: https://api.circle.com security: - BearerAuth: [] tags: - name: Wallet Sets - name: Wallets - name: Signing - name: Transactions - name: Token Lookup paths: /v1/w3s/developer/transactions/transfer: post: tags: - Transactions summary: Create a transfer transaction description: > Initiates an on-chain digital asset transfer from a specified developer-controlled wallet. To identify the wallet, you must provide either `walletId`, or both `walletAddress` and `blockchain` in the request body. operationId: createDeveloperTransactionTransfer parameters: - $ref: '#/components/parameters/XRequestId' requestBody: $ref: '#/components/requestBodies/CreateTransferTransactionForDeveloper' responses: '200': content: application/json: schema: $ref: >- #/components/schemas/CreateTransferTransactionForDeveloperResponse description: >- Returns the existing transaction 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/CreateTransferTransactionForDeveloperResponse description: A new transaction is created 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: 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: CreateTransferTransactionForDeveloper: content: application/json: schema: title: CreateTransferTransactionForDeveloperRequest type: object required: - destinationAddress - entitySecretCiphertext - idempotencyKey properties: idempotencyKey: $ref: '#/components/schemas/IdempotencyKey' amounts: $ref: '#/components/schemas/TransferAmounts-2' destinationAddress: $ref: '#/components/schemas/Address' entitySecretCiphertext: $ref: '#/components/schemas/EntitySecretCiphertext' 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' nftTokenIds: $ref: '#/components/schemas/NftTokenIds' refId: $ref: '#/components/schemas/TransactionReferenceId' tokenId: $ref: '#/components/schemas/TokenId' tokenAddress: $ref: '#/components/schemas/TokenAddress' blockchain: anyOf: - $ref: '#/components/schemas/TransferBlockchain' - $ref: '#/components/schemas/TokenBlockchain' walletId: $ref: '#/components/schemas/WalletId' walletAddress: $ref: '#/components/schemas/Address' description: Create transaction for developer request required: true schemas: CreateTransferTransactionForDeveloperResponse: title: CreateTransferTransactionForDeveloperResponse type: object properties: data: type: object required: - id - state properties: id: $ref: '#/components/schemas/Id' state: $ref: '#/components/schemas/TransactionState' 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 TransferAmounts-2: title: TransferAmounts type: array items: type: string description: >- Transfer amounts in decimal number format, at least one element is required for transfer. For ERC721 token transfer, the amounts field is required to be ["1"] (array with "1" as the only element). example: - '6.62607015' minItems: 1 Address: title: Address description: > Blockchain generated unique identifier, associated with wallet (account), smart contract or other blockchain objects. type: string example: '0xca9142d0b9804ef5e239d3bc1c7aa0d1c74e7350' EntitySecretCiphertext: type: string description: > A base64 string expression of the entity secret ciphertext. The entity secret should be encrypted by the entity public key. Circle mandates that the entity secret ciphertext is unique for each API request. format: byte example: >- 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 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 NftTokenIds: title: NftTokenIds type: array description: >- List of NFT token IDs corresponding with the NFTs to transfer. Batch transfers are supported only for ERC-1155 tokens. The length of NFT token IDs must match the length of amounts. items: $ref: '#/components/schemas/NftTokenId' TransactionReferenceId: type: string example: grouptransaction123 description: Optional reference or description used to identify the transaction. TokenId: title: TokenId type: string format: uuid description: >- System generated identifier of the token. Excluded with `tokenAddress` and `tokenBlockchain`. TokenAddress: title: TokenAddress type: string description: >- Blockchain address of the transferred token. Empty for native tokens. Excluded with `tokenId`. TransferBlockchain: title: TransferBlockchain type: string description: > Blockchain associated with the transfer transaction. Required when either of `walletAddress` or `tokenAddress` is provided. enum: - ETH - ETH-SEPOLIA - AVAX - AVAX-FUJI - MATIC - MATIC-AMOY - SOL - SOL-DEVNET - ARB - ARB-SEPOLIA - UNI - UNI-SEPOLIA - BASE - BASE-SEPOLIA - OP - OP-SEPOLIA - APTOS - APTOS-TESTNET - ARC - ARC-TESTNET - MONAD - MONAD-TESTNET example: MATIC-AMOY TokenBlockchain: title: TokenBlockchain type: string description: > Blockchain of the transferred token. Required if `tokenId` is not provided. The `blockchain` and `tokenId` fields are mutually exclusive. enum: - ETH - ETH-SEPOLIA - AVAX - AVAX-FUJI - MATIC - MATIC-AMOY - SOL - SOL-DEVNET - ARB - ARB-SEPOLIA - UNI - UNI-SEPOLIA - BASE - BASE-SEPOLIA - OP - OP-SEPOLIA - APTOS - APTOS-TESTNET - ARC - 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 Id: type: string format: uuid description: System-generated unique identifier of the resource. example: c4d1da72-111e-4d52-bdbf-2e74a2d803d5 TransactionState: title: TransactionState type: string description: Current state of the transaction. enum: - INITIATED - CLEARED - QUEUED - SENT - STUCK - CONFIRMED - COMPLETE - FAILED - DENIED - CANCELLED 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. NftTokenId: title: NftTokenId type: string description: The NFT token ID. example: '2' 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. ````