> ## 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. # Get withdrawal status > Returns the status and transfer details of a specified withdrawal group. ## OpenAPI ````yaml openapi/xreserve.yaml get /v1/withdrawal/{withdrawalId} openapi: 3.0.2 info: title: Circle xReserve version: 1.0.0 description: > xReserve enables transfers between USDC and USDC-backed tokens across supported blockchain networks using a secure attestation system. servers: - url: https://xreserve-api-testnet.circle.com description: Testnet - url: https://xreserve-api.circle.com description: Mainnet security: [] tags: - name: xReserve description: xReserve endpoints paths: /v1/withdrawal/{withdrawalId}: get: tags: - xReserve summary: Get withdrawal status description: Returns the status and transfer details of a specified withdrawal group. operationId: getWithdrawalStatus parameters: - $ref: '#/components/parameters/WithdrawalId' responses: '200': $ref: '#/components/responses/WithdrawalResponse' '400': $ref: '#/components/responses/ErrorResponse' '404': $ref: '#/components/responses/ErrorResponse' '500': $ref: '#/components/responses/ErrorResponse' components: parameters: WithdrawalId: in: path name: withdrawalId required: true schema: type: string format: uuid description: >- Unique identifier of the withdrawal group returned by the `/withdraw` endpoint. example: 123e4567-e89b-12d3-a456-426614174000 responses: WithdrawalResponse: description: Successfully retrieved withdrawal status. content: application/json: schema: $ref: '#/components/schemas/WithdrawalResponse' ErrorResponse: description: Standard error response. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' schemas: WithdrawalResponse: type: object description: Contains withdrawal status and details properties: withdrawalId: type: string format: uuid description: The unique identifier of the withdrawal group. example: 6149dc3d-71bf-4d57-8cc1-5e2d4c0a8e70 burnTxId: type: string pattern: ^0x[a-fA-F0-9]+$ description: The transaction ID of the burn on the remote network. example: '0xabcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890' status: type: string enum: - created - verified - confirmed - finalized - expired - failed description: > The status of the withdrawal. - 'created': The withdrawal has been created but the burn transaction on the remote network has not been verified yet. - 'verified': The burn transaction on the remote network has been successfully verified. The attestation is available but has been submitted on chain yet. - 'confirmed': The attestation has been submitted onchain but the transaction has not been finalized yet. - 'finalized': The transaction has been successfully finalized. This state is terminal. - 'expired': The attestation expired before it was used. This state is terminal and can be retried. - 'failed': The verification failed. The withdrawal cannot proceed. This state is terminal and cannot be retried. attestationPayload: type: string pattern: ^0x[a-fA-F0-9]*$ description: The full attestation payload. attestation: type: string pattern: ^0x[a-fA-F0-9]*$ description: The xReserve attestation signature. useCircleForwarding: type: boolean description: >- Indicates whether Circle should forward the transaction and release funds on either a CCTP supported blockchain or another remote blockchain. example: true transactionHash: type: string pattern: ^0x[a-fA-F0-9]{64}$ description: The hash of forwarded transaction. example: '0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef' failureReason: type: string description: The reason for failure. Returned when the `status` is 'failed'. example: verification_failed transferSpecHashes: type: array description: >- List of transfer specification hashes for all withdrawal intents in the group. items: type: string pattern: ^0x[a-fA-F0-9]{64}$ example: - '0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef' required: - withdrawalId - burnTxId - status - useCircleForwarding - transferSpecHashes ErrorResponse: type: object description: Standard error response. properties: success: type: boolean example: false message: type: string example: Error message ````