# Circle Docs: Liquidity services

> Developer documentation for Circle's developer tools

> ## 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.

## Liquidity services

- [Liquidity services](https://developers.circle.com/liquidity-services.md): Access institutional-grade tools for minting USDC and EURC directly from Circle, executing stablecoin FX trades, and offering stablecoin-backed accounts to your business customers.

### Mint

- [Circle Mint](https://developers.circle.com/circle-mint.md): Mint and redeem USDC, EURC, and cirBTC directly from Circle.

#### Get started

- [Set up your account and API key](https://developers.circle.com/circle-mint/quickstarts/getting-started.md): Create a sandbox account, generate an API key, and make your first Circle Mint API request.
- [Supported chains and currencies](https://developers.circle.com/circle-mint/references/supported-chains-and-currencies.md): Blockchains and currencies supported by Circle Mint and related APIs.
- [Blockchain confirmations](https://developers.circle.com/circle-mint/references/blockchain-confirmations.md): Confirmation requirements and approximate times for each blockchain supported by Circle Mint.
- [Supported countries](https://developers.circle.com/circle-mint/references/supported-countries.md): Countries that support wire transfers for minting and redeeming USDC.
- [Quickstart: Mint and redeem USDC](https://developers.circle.com/circle-mint/quickstarts/mint-and-redeem.md): Deposit fiat to mint USDC, transfer it onchain, and redeem USDC back to fiat using the Circle Mint API.
- [Quickstart: Mint and redeem cirBTC](https://developers.circle.com/circle-mint/quickstarts/mint-and-redeem-cirbtc.md): Deposit BTC to mint cirBTC, transfer cirBTC onchain, and redeem cirBTC back to BTC using the Circle Mint API.

#### Mint and redeem

- [How minting and redemption works](https://developers.circle.com/circle-mint/concepts/how-minting-works.md): Understand how Circle Mint converts fiat to USDC (minting) and USDC back to fiat (redemption), including settlement timing, account structure, and compliance requirements.
- [How-to: Deposit fiat](https://developers.circle.com/circle-mint/howtos/deposit-fiat.md): Link a bank account and deposit fiat to mint USDC or EURC in your Circle Mint account.
- [How-to: Withdraw fiat](https://developers.circle.com/circle-mint/howtos/withdraw-fiat.md): Redeem USDC or EURC to fiat and withdraw funds to your bank account using the Circle Mint API.
- [How-to: Transfer USDC onchain](https://developers.circle.com/circle-mint/howtos/transfer-on-chain.md): Receive USDC and EURC via deposit addresses and send them to external blockchain wallets using the Circle Mint API.

#### Exchange currencies

- [Cross-currency exchange](https://developers.circle.com/circle-mint/concepts/cross-currency-exchange.md): Understand how the Mint Exchange API exchanges local fiat for USDC and swaps between USDC and EURC through banking partners, the quote-trade-settle model, and delivery-versus-payment settlement.
- [How-to: Exchange currencies](https://developers.circle.com/circle-mint/howtos/exchange-currencies.md): Use the Mint Exchange API to exchange local fiat for USDC or swap between USDC and EURC through a quote, trade, and settlement flow.

#### Credit

- [Credit API](https://developers.circle.com/circle-mint/concepts/credit-api.md): Understand how the Credit API exposes Circle Mint's Settlement Advance and Line of Credit products, the credit-line model, and the lifecycle of credit transfers and repayments.
- [Quickstart: Reserve and repay a settlement advance](https://developers.circle.com/circle-mint/quickstarts/settlement-advance.md): Check your credit line, reserve funds, send a wire and upload proof, and observe disbursement and repayment for a Settlement Advance draw.
- [Quickstart: Draw and repay a line of credit](https://developers.circle.com/circle-mint/quickstarts/line-of-credit.md): Check your credit line, request an auto-disbursed draw, observe fees, and repay with crypto or wire to close out a Line of Credit transfer.

#### Digital Asset-Backed Borrowing

- [How Digital Asset-Backed Borrowing works](https://developers.circle.com/circle-mint/concepts/digital-asset-backed-borrowing.md): The concepts behind borrowing USDC against cirBTC: the MSCA wallet, the lending market, and how loans move through their lifecycle.
- [Quickstart: Borrow USDC against cirBTC collateral](https://developers.circle.com/circle-mint/quickstarts/borrow-with-cirbtc.md): Provision a wallet, discover an available lending market, borrow USDC against cirBTC collateral, and confirm the funds landed in your Mint balance.
- [How-to: Repay a loan](https://developers.circle.com/circle-mint/howtos/repay-loan.md): Repay part or all of an open loan's outstanding USDC debt and release your cirBTC collateral back to your Circle Mint balance.
- [How-to: Add collateral to a loan](https://developers.circle.com/circle-mint/howtos/add-collateral.md): Post additional cirBTC as collateral to an open loan to lower its LTV and restore its health factor after a margin call.
- [How-to: Add another wallet owner](https://developers.circle.com/circle-mint/howtos/add-wallet-owner.md): Register an additional passkey as an authorized owner on your MSCA to extend recovery coverage across additional devices.

#### Institutional distribution

- [Institutional API](https://developers.circle.com/circle-mint/concepts/institutional-api.md): Understand how the Institutional API lets Circle Mint distributors mint, redeem, and transfer on behalf of compliance-screened external entities with their own per-entity wallets.
- [Manage institutional subaccounts](https://developers.circle.com/circle-mint/quickstarts/manage-institutional-subaccounts.md): Step-by-step guide for Circle Mint distributors to create external entities, mint and redeem on their behalf, transfer USDC onchain, and query entity-scoped activity.

#### Learn more

- [CAMT.053 daily statements](https://developers.circle.com/circle-mint/references/camt053-statements.md): Integrate ISO 20022 CAMT.053 daily statement XML from Circle Mint for treasury and reconciliation workflows.
- [Supported payment rails](https://developers.circle.com/circle-mint/references/supported-payment-rails.md): Reference for the fiat payment rails Circle Mint supports—Fedwire, SWIFT, RTP, SEPA, SPEI, CHATS, PIX, CUBIX, and book transfers—including currencies, regions, settlement timing, and API endpoints.
- [Webhook notifications](https://developers.circle.com/circle-mint/references/webhook-notifications.md): Reference for Circle Mint webhook event topics with example payloads.
- [Sandbox to production](https://developers.circle.com/circle-mint/references/sandbox-and-testing.md): Transition your Circle Mint integration from the sandbox environment to production.
- [Travel rule compliance](https://developers.circle.com/circle-mint/references/travel-rule-compliance.md): Travel Rule thresholds, schemas, and failure modes for Circle Mint Stablecoin Payouts and CIRCLE_FR Stablecoin Payins.

##### mTLS Authentication

- [How mTLS authentication works](https://developers.circle.com/circle-mint/mtls-authentication.md): Learn how mutual TLS authentication adds a transport-layer certificate check to Circle Mint API access, as a MiCA requirement or an optional security enhancement.
- [How-to: Set up mTLS authentication](https://developers.circle.com/circle-mint/set-up-mtls-authentication.md): Configure mutual TLS authentication for Circle Mint API calls using a client certificate issued by Circle and an API key.
- [How-to: Rotate an mTLS API key](https://developers.circle.com/circle-mint/rotate-mtls-api-key.md): Rotate your API key for an mTLS-enabled Circle Mint entity before the mandatory 180-day expiration.
- [How-to: Rotate an mTLS client certificate](https://developers.circle.com/circle-mint/rotate-mtls-certificate.md): Rotate the client certificate for an mTLS-enabled Circle Mint entity before it expires.

### Match

- [Circle Match](https://developers.circle.com/circle-match.md): Batch-auction venue where participants fund positions in advance to match USDC burn demand against USDC mint demand for eligible Circle Mint customers

#### Get started

- [Place your first order](https://developers.circle.com/circle-match/quickstarts/place-your-first-order.md): Submit a burn order to the Match sandbox and check its status.

##### Concepts

- [How Match works](https://developers.circle.com/circle-match/concepts/how-it-works.md): Explains the batch-auction mechanics that govern Match, including auction cadence, uniform clearing fee, clearing objective, allocation priority, and order lifecycle.
- [Match funding model](https://developers.circle.com/circle-match/concepts/funding-model.md): How burn-side and mint-side participants prefund their Match activity, and what happens to balances before, during, and after a fill.

#### Place orders

- [How-to: Place and manage orders](https://developers.circle.com/circle-match/howtos/place-orders.md): Place BURN and MINT orders, apply filters when listing, and trace rolled orders using lineage fields.
- [How-to: Cancel and modify orders](https://developers.circle.com/circle-match/howtos/cancel-and-modify-orders.md): Cancel a single resting order, cancel all orders in an auction, or change an order's fee limit before the auction clears.

#### Manage your account

- [How-to: Fund your account](https://developers.circle.com/circle-match/howtos/fund-your-account.md): Prepare burn-side and mint-side balances so you can place Match orders.
- [How-to: Withdraw funds](https://developers.circle.com/circle-match/howtos/withdraw-funds.md): Convert your Match-only USDC back to USD through a no-fee wire to your linked fiat account.
- [How-to: Monitor your account](https://developers.circle.com/circle-match/howtos/monitor-account.md): Call GET /v1/match/account to check your Match balance and activity totals, and learn when to use order records instead.

#### Real-time updates

- [How-to: Subscribe to real-time updates](https://developers.circle.com/circle-match/howtos/subscribe-to-real-time-updates.md): Open a WebSocket connection to Match and subscribe to market or account channels for live auction and order events.
- [WebSocket reference](https://developers.circle.com/circle-match/references/websocket-reference.md): Complete reference for the Match WebSocket protocol, including connection setup, session frames, client messages, channel events, and reconnection behavior.

### StableFX

- [StableFX](https://developers.circle.com/stablefx.md): Institutional-grade stablecoin FX engine built on Arc
- [Grant USDC allowance to Permit2](https://developers.circle.com/stablefx/howtos/grant-usdc-allowance-permit2.md): Use Uniswap's Permit2 contract to grant USDC allowance to the StableFX FxEscrow contract
- [How-to: Fund a trade with a settlement advance](https://developers.circle.com/stablefx/howtos/fund-trade-settlement-advance.md): Use your Settlement Advance credit line to fund the maker leg of a confirmed StableFX trade through delegate funding.
- [Test your StableFX integration as a taker](https://developers.circle.com/stablefx/tutorials/test-stablefx-integration-taker.md): Test your integration with the StableFX API and smart contracts on the taker side
- [Test your StableFX integration as a maker](https://developers.circle.com/stablefx/tutorials/test-stablefx-integration-maker.md): Test your integration with the StableFX API and smart contracts on the maker side

#### Get started

- [StableFX supported currencies](https://developers.circle.com/stablefx/references/supported-currencies.md): The currencies supported by StableFX for FX swaps
- [StableFX Talos integration for makers](https://developers.circle.com/stablefx/concepts/maker-talos-integration.md): Integrate with StableFX as a maker on Talos

##### Quickstarts

- [Quickstart: Create an FX trade as a taker](https://developers.circle.com/stablefx/quickstarts/fx-trade-taker.md): Use the StableFX API to create an FX trade on the taker side
- [Quickstart: Fulfill an FX trade as a maker](https://developers.circle.com/stablefx/quickstarts/fx-trade-maker.md): Use the StableFX API to fulfill an FX trade on the maker side
- [Execute your first trade in the Console](https://developers.circle.com/stablefx/quickstarts/console-first-trade.md): Go from zero to your first StableFX trade using the console UI—no code required.

#### Console

- [StableFX Console](https://developers.circle.com/stablefx/concepts/console-overview.md): A self-service interface for trading stablecoins, managing API keys, and settling trades onchain—no code required.
- [How-to: Generate a StableFX API key](https://developers.circle.com/stablefx/howtos/get-api-key.md): Create a StableFX API key in the Hub to authenticate API requests.
- [How-to: Connect your wallet](https://developers.circle.com/stablefx/howtos/connect-wallet-console.md): Connect an EVM-compatible wallet to the StableFX Console for signing and funding trades.
- [How-to: Create a trade in the Console](https://developers.circle.com/stablefx/howtos/create-trade-console.md): Request a quote, sign with your wallet, and execute a trade from the StableFX Console.
- [How-to: Fulfill a trade as a maker](https://developers.circle.com/stablefx/howtos/fulfill-trade-console.md): Review, sign, and fund confirmed trades from the maker view in the StableFX Console.
- [How-to: Settle trades in the Console](https://developers.circle.com/stablefx/howtos/settle-trades-console.md): Fund individual trades or batch-settle multiple trades from the StableFX Console.
- [Console roles and permissions](https://developers.circle.com/stablefx/references/console-roles-permissions.md): Understand user roles, permissions, and access controls in the StableFX Console.

#### Learn more

- [StableFX technical guide](https://developers.circle.com/stablefx/concepts/technical-guide.md): Technical implementation details for StableFX
- [StableFX risk buffers](https://developers.circle.com/stablefx/concepts/risk-buffers.md): Understand how risk buffers protect counterparties during StableFX trade execution
- [StableFX settlement advance](https://developers.circle.com/stablefx/concepts/settlement-advance.md): Understand how Settlement Advance lets a maker borrow local stablecoin inventory against a Circle-issued credit line to fund and instantly settle a confirmed StableFX trade.
- [StableFX contract interfaces](https://developers.circle.com/stablefx/references/contract-interfaces.md): User-facing methods of the StableFX contract
- [StableFX trade states](https://developers.circle.com/stablefx/references/trade-states.md): Learn about the different states a StableFX trade can be in
- [Magic numbers for testing StableFX](https://developers.circle.com/stablefx/references/testing-magic-numbers.md): Magic numbers you can use to create certain trade outcomes for testing

### Digital Asset Accounts

- [Digital Asset Accounts](https://developers.circle.com/digital-asset-accounts.md): Stablecoin-backed account infrastructure for distributors and their business end customers

#### Get started

- [Account structure](https://developers.circle.com/digital-asset-accounts/concepts/account-structure.md): Understand the account hierarchy, roles, and subaccount model in Digital Asset Accounts
- [EEA operations under MiCA](https://developers.circle.com/digital-asset-accounts/concepts/eea-and-mica.md): How Digital Asset Accounts operates in the EEA under Circle France SAS's MiCA authorization, including booking patterns and asset segregation.
- [Supported currencies and blockchains](https://developers.circle.com/digital-asset-accounts/references/supported-currencies-and-blockchains.md): Currencies and blockchains supported by Digital Asset Accounts
- [Onboard customers](https://developers.circle.com/digital-asset-accounts/quickstarts/onboard-customers.md): Create a business client, complete KYB verification, and get an active stablecoin account using the End User Onboarding API in sandbox
- [How-to: Onboard EEA customers](https://developers.circle.com/digital-asset-accounts/howtos/onboard-eea-customers.md): Onboard EEA business end users under the MiCA authorization of Circle France SAS.
- [Fund your digital asset account with a wire deposit](https://developers.circle.com/digital-asset-accounts/quickstarts/fund-account-with-wire-deposit.md): Simulate a wire deposit and check your account balance using the Digital Asset Accounts API in sandbox

#### Fiat operations

- [How-to: Wire deposits and withdrawals](https://developers.circle.com/digital-asset-accounts/howtos/wire-deposits-and-withdrawals.md): Link bank accounts, deposit fiat, and withdraw stablecoins through wire transfers

#### Crypto operations

- [How-to: Create deposit addresses](https://developers.circle.com/digital-asset-accounts/howtos/create-deposit-addresses.md): Generate blockchain deposit addresses to receive stablecoin deposits
- [How-to: Send crypto transfers](https://developers.circle.com/digital-asset-accounts/howtos/crypto-transfers.md): Register recipient addresses and send stablecoins to external blockchain wallets
- [How-to: Use self-hosted wallets](https://developers.circle.com/digital-asset-accounts/howtos/self-hosted-wallets.md): Register and verify an end user's self-hosted wallet, then transfer funds to it from a Digital Asset Account

#### Internal transfers

- [How-to: Transfer funds internally](https://developers.circle.com/digital-asset-accounts/howtos/internal-transfers.md): Move funds instantly between accounts with no blockchain fees

#### Strong Customer Authentication

- [How Strong Customer Authentication works](https://developers.circle.com/digital-asset-accounts/concepts/strong-customer-authentication.md): Why Digital Asset Accounts asks end users to approve sensitive operations with a passkey, what an approval proves, and where the trust boundary sits.
- [How-to: Implement Strong Customer Authentication](https://developers.circle.com/digital-asset-accounts/howtos/strong-customer-authentication.md): Check whether an end user requires SCA, enroll their passkey, and complete SCA-protected operations using the challenge–assertion flow.

#### Learn more

- [Direct end-user custody model](https://developers.circle.com/digital-asset-accounts/concepts/custody-model.md): Understand how Circle's Direct End-User Custody model works for Stablecoin Accounts
- [EEA API behavior](https://developers.circle.com/digital-asset-accounts/references/eea-api-behavior.md): EEA API controls for Digital Asset Accounts integrations, including mTLS, SCA, the platform address book, fail-closed asset scope, and MiCA balance reporting.
- [Receipts and disclosures](https://developers.circle.com/digital-asset-accounts/references/receipts-and-disclosures.md): Statutory receipt and pre-transaction disclosure requirements you must implement when building on Circle Digital Asset Accounts (DAA).
- [Limits and risk ratings](https://developers.circle.com/digital-asset-accounts/concepts/limits-and-risk-ratings.md): Understand risk tiers, transaction limits, and how risk ratings affect account capabilities
- [Transaction states](https://developers.circle.com/digital-asset-accounts/references/transaction-states.md): Learn about the different states for deposits, withdrawals, and transfers
- [Sandbox environment](https://developers.circle.com/digital-asset-accounts/references/testing-in-sandbox.md): Use Circle's sandbox environment for safe development and testing of your Digital Asset Accounts integration
- [Going to production](https://developers.circle.com/digital-asset-accounts/references/going-to-production.md): Transition your Digital Asset Accounts integration from sandbox to production

##### Compliance obligations

- [Compliance obligations](https://developers.circle.com/digital-asset-accounts/references/compliance-obligations.md): Regulatory and contractual obligations for Digital Asset Accounts distributors.
- [Regulated customer notices](https://developers.circle.com/digital-asset-accounts/references/compliance-obligations/regulated-customer-notices.md): Lifecycle notice requirements for Digital Asset Accounts distributors.
- [Record retention](https://developers.circle.com/digital-asset-accounts/references/compliance-obligations/record-retention.md): Record retention requirements for Digital Asset Accounts distributors.

### End User Onboarding

- [End User Onboarding](https://developers.circle.com/end-user-onboarding.md): Programmatically onboard your customers to Circle products using the End User Onboarding API

#### Get started

- [Application types and states](https://developers.circle.com/end-user-onboarding/references/application-states.md): Reference for all application types and their statuses
- [Submit onboarding application](https://developers.circle.com/end-user-onboarding/quickstarts/submit-onboarding-application.md): Submit an onboarding application using the End User Onboarding API in sandbox

#### Build applications

- [How-to: Create and populate applications](https://developers.circle.com/end-user-onboarding/howtos/create-and-populate-applications.md): Retrieve onboarding applications, discover the schema, and save section data
- [How-to: Upload documents](https://developers.circle.com/end-user-onboarding/howtos/upload-documents.md): Upload, list, and manage supporting documents for onboarding applications
- [Document file rules](https://developers.circle.com/end-user-onboarding/references/document-file-rules.md): Filename characters, size limits, accepted types, and upload error codes for End User Onboarding
- [How-to: Collect device risk signals](https://developers.circle.com/end-user-onboarding/howtos/collect-device-risk-signals.md): Run a web device check with @circle-fin/device-checks, then reuse the deviceId it returns for Stablecoin KYB submission and for Digital Asset Accounts money movement
- [How-to: Submit and track applications](https://developers.circle.com/end-user-onboarding/howtos/submit-and-track-applications.md): Submit applications for review and handle Requests for Information
- [How-to: Handle requests for information](https://developers.circle.com/end-user-onboarding/howtos/handle-rfis.md): Respond to compliance team RFIs by updating data, uploading and saving documents, and resubmitting applications
- [Webhook notifications](https://developers.circle.com/end-user-onboarding/references/webhook-notifications.md): Reference for End User Onboarding webhook event types with example payloads.
- [Magic numbers for testing End User Onboarding](https://developers.circle.com/end-user-onboarding/references/testing-magic-numbers.md): Magic numbers you can use to drive an End User Onboarding application into review, RFI, or denial outcomes in the sandbox

#### Concepts

- [Conditional logic](https://developers.circle.com/end-user-onboarding/concepts/conditional-logic.md): Understand how Nature of Business and JSON Schema conditionals control which fields are required
- [Array sections](https://developers.circle.com/end-user-onboarding/concepts/array-sections.md): Understand how to work with repeatable entity sections like beneficial owners and directors