> ## 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 an account transfer > Create an internal transfer from an account to another account under the same parent. Supported paths are subaccount to subaccount, main wallet to subaccount, and subaccount to main wallet. Cross-parent transfers are rejected. This endpoint creates internal transfers only. Sending funds to an external blockchain address is not supported, and both `source` and `destination` must be of type `account`. ## OpenAPI ````yaml openapi/managed-payments.yaml post /v1/accounts/transfers openapi: 3.0.2 info: version: ${version} title: Managed Payments API description: | The Managed Payments API enables Payment Service Providers (PSPs) to create and manage sub-client accounts for stablecoin settlement, and to send fiat payouts to registered beneficiaries worldwide. servers: - url: https://api-sandbox.circle.com - url: https://api.circle.com security: [] tags: - name: Managed Payments Accounts description: Create and manage sub-client accounts for Managed Payments PSPs. - name: Managed Payments Credit description: Get credit line details and wire instructions for repayment. - name: Managed Payments Credit Transfers description: Create and manage credit transfers (drawdowns) against a credit line. - name: Managed Payments Transfers description: >- Create and manage internal account-to-account transfers for Managed Payments. - name: Managed Payments Fiat Payouts description: > Register and manage fiat payout beneficiaries, discover supported corridors and field requirements, and create locked FX quotes for cross-border fiat payouts. paths: /v1/accounts/transfers: post: tags: - Managed Payments Transfers summary: Create an account transfer description: > Create an internal transfer from an account to another account under the same parent. Supported paths are subaccount to subaccount, main wallet to subaccount, and subaccount to main wallet. Cross-parent transfers are rejected. This endpoint creates internal transfers only. Sending funds to an external blockchain address is not supported, and both `source` and `destination` must be of type `account`. operationId: createManagedPaymentsAccountTransfer requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/AccountTransferCreationRequest' example: idempotencyKey: ba943ff1-ca16-49b2-ba55-1057e70ca5c7 source: type: account id: '1000565227' destination: type: account id: '1000662322' amount: amount: '10.00' currency: USD responses: '201': description: Successfully created a transfer. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' content: application/json: schema: title: CreateManagedPaymentsAccountTransferResponse properties: data: $ref: '#/components/schemas/CreatedAccountTransfer' example: data: id: b8627ae8-732b-4d25-b947-1df8f4007a29 source: type: account id: '1000565227' description: Your Payments Account destination: type: account id: '1000662322' description: Merchant Subledger Account amount: amount: '10.00' currency: USD status: pending createDate: '2020-04-10T02:13:30.000Z' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/NotAuthorized' '403': $ref: '#/components/responses/Forbidden' '500': $ref: '#/components/responses/InternalServerError' security: - bearerAuth: [] components: schemas: AccountTransferCreationRequest: type: object description: Request body for creating an internal account-to-account transfer. required: - idempotencyKey - destination - amount properties: idempotencyKey: $ref: '#/components/schemas/IdempotencyKey' destination: description: The destination account for an internal transfer. type: object required: - type - id properties: type: type: string enum: - account id: description: The identifier of the destination account. type: string example: '1000565227' amount: $ref: '#/components/schemas/FiatMoneyUsd' source: description: The source of the transfer. The type must be `account`. type: object required: - id - type properties: id: description: Identifier for the source account. type: string example: '1000565227' type: type: string enum: - account CreatedAccountTransfer: type: object description: > A transfer of funds returned by the create transfer endpoint. Both source and destination are always accounts, because this endpoint only creates internal account-to-account transfers. required: - id - source - destination - amount - status properties: id: $ref: '#/components/schemas/Id' source: $ref: '#/components/schemas/TransferSourceAccountLocation' destination: $ref: '#/components/schemas/TransferDestinationAccountLocation' amount: $ref: '#/components/schemas/FiatMoneyUsd' fees: description: >- An array of fees applied to a transaction. This is only available when there is at least one non-zero fee. type: array items: $ref: '#/components/schemas/Fee' status: description: >- Status of the transfer. Status `pending` indicates that the transfer is in the process of running; `complete` indicates it finished successfully; `failed` indicates it failed. type: string enum: - pending - complete - failed errorCode: $ref: '#/components/schemas/AccountTransferErrorCode' createDate: $ref: '#/components/schemas/UtcTimestamp' description: The create date of the transfer. IdempotencyKey: type: string description: >- Universally unique identifier (UUID v4) idempotency key. This key is utilized to ensure exactly-once execution of mutating requests. format: uuid example: ba943ff1-ca16-49b2-ba55-1057e70ca5c7 FiatMoneyUsd: type: object required: - amount - currency properties: amount: description: Magnitude of the amount, in units of the currency, with a `.`. type: string example: '3.14' currency: description: Currency code. type: string enum: - USD Id: type: string description: Unique system generated identifier for the entity. format: uuid example: b8627ae8-732b-4d25-b947-1df8f4007a29 TransferSourceAccountLocation: description: A source account location. type: object required: - type - id properties: type: type: string enum: - account id: type: string description: The identifier of the source account. example: '1000662322' description: type: string description: The human-readable name of the source account. example: Your Payments Account TransferDestinationAccountLocation: description: A destination account location. type: object required: - type - id properties: type: type: string enum: - account id: type: string description: The identifier of the destination account. example: '1000662322' description: type: string description: The human-readable name of the destination account. example: Merchant Subledger Account address: type: string description: > The deposit address of the destination account. Present when the transfer originates from a blockchain source (e.g. a crypto deposit). example: '0xecf270635e22f87b9d9ed501eca86e74caf59623' addressTag: $ref: '#/components/schemas/AddressTag' Fee: type: object required: - amount - currency - type properties: amount: type: string description: Magnitude of the fee amount, in units of the currency, with a `.`. example: '10.00' currency: type: string description: Currency code for the amount. enum: - USD type: type: string description: Category of the fee. enum: - network AccountTransferErrorCode: type: string description: >- Indicates the failure reason of a transfer. Only present for transfers in a `failed` state. nullable: true enum: - transfer_failed - transfer_denied - blockchain_error - insufficient_funds - invalid_crypto_address UtcTimestamp: type: string description: ISO-8601 UTC date/time format. example: '2020-04-10T02:13:30.000Z' AddressTag: type: string description: >- The secondary identifier for a blockchain address. An example of this is the memo field on the Stellar network, which can be text, id, or hash format. nullable: true example: '123456789' headers: XRequestId: description: >- Universally unique identifier (UUID v4) for the request. Helpful for identifying a request when communicating with Circle support. schema: type: string format: uuid example: 2adba88e-9d63-44bc-b975-9b6ae3440dde responses: BadRequest: description: The request cannot be processed due to a client error. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' content: application/json: schema: type: object title: BadRequest required: - code - message properties: code: type: integer example: 400 message: type: string example: Something went wrong. example: code: 400 message: Bad request. examples: response: value: code: 400 message: Bad request. NotAuthorized: description: >- The request has not been applied because it lacks valid authentication credentials. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' content: application/json: schema: type: object title: NotAuthorized required: - code - message properties: code: type: integer example: 400 message: type: string example: Something went wrong. example: code: 401 message: Malformed authorization. examples: response: value: code: 401 message: Malformed authorization. Forbidden: description: >- The request provides authentication, but the authenticated user does not possess sufficient permissions for accessing this resource. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' content: application/json: schema: type: object title: Forbidden required: - code - message properties: code: type: integer example: 400 message: type: string example: Something went wrong. example: code: 3 message: Forbidden examples: response: value: code: 3 message: Forbidden InternalServerError: description: Unexpected server error. headers: X-Request-Id: $ref: '#/components/headers/XRequestId' content: application/json: schema: type: object title: InternalServerError required: - code - message properties: code: type: integer example: 400 message: type: string example: Something went wrong. example: code: 500 message: Internal server error. examples: response: value: code: 500 message: Internal server error. securitySchemes: bearerAuth: type: http scheme: bearer ````