> ## 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.

# CCTP Sui packages and interfaces

> Move packages and shared objects for CCTP on Sui

CCTP on Sui is implemented across four Move packages: `MessageTransmitterV2`,
`TokenMessengerMinterV2`, `StablecoinHandler`, and `CctpExtensions`. The Sui
CCTP implementation uses
[Programmable Transaction Blocks (PTBs)](https://docs.sui.io/concepts/transactions/prog-txn-blocks)
to compose the required function calls atomically in a single transaction.

For working end-to-end examples, see
[Transfer USDC between Sui and Arc](/cctp/quickstarts/transfer-usdc-sui-arc).

## Package addresses

<Note>
  **Package IDs** identify deployed Move packages. Use them in function call
  targets (for example, `{packageId}::module::function`). **State object IDs**
  identify onchain shared objects, such as configuration or shared state, and are
  passed as arguments when a transaction interacts with protocol state.
</Note>

### Testnet

#### Package IDs

| Package | [Domain](/cctp/concepts/supported-chains-and-domains#domain-identifiers) | Address |
| :- | :- | :- |
| `MessageTransmitterV2` | 8 | `0xe9678cd42a81886e18e21361088071f275105636a4d3751e1d7f255211f73bbe` |
| `TokenMessengerMinterV2` | 8 | `0x267d3c0cb776eace2840f27e4d33da9c6d952f9749403f1fe6579f4962ed3c64` |
| `StablecoinHandler` | 8 | `0xbe8479044396a45e07de2c7f14789c35b8338406eebc53b2527da56839a91561` |
| `CctpExtensions` | 8 | `0x3cdb05f9a035c147410f5a9cfe2ccb741f4ab3cd59411e86714ce4b45e2c4d95` |

#### State object IDs

| Object | Object ID |
| :- | :- |
| `MessageTransmitterV2` | `0xfee3a2b47f9ef2de2405fc63d79194307945f8ea768815cfc46083bc20fbe6ed` |
| `TokenMessengerMinterV2` | `0x72cb55cd14d01e6361386d6ea93eecda9fa1efc3c202b8dd69c1e4683e4c0ca0` |
| `StablecoinHandler` | `0xfbd9c0517c4f0e1817445ee2be598806e3c392a465d7e3d773d1055f3f0eed32` |
| USDC Treasury | `0x7170137d4a6431bf83351ac025baf462909bffe2877d87716374fb42b9629ebe` |

### Mainnet

#### Package IDs

| Package | [Domain](/cctp/concepts/supported-chains-and-domains#domain-identifiers) | Address |
| :- | :- | :- |
| `MessageTransmitterV2` | 8 | `0x16bcfcfc465f96281663a344641c017de84529370e11aa3879d0dce43ad6db87` |
| `TokenMessengerMinterV2` | 8 | `0xeb14978abfe93a37c5d5bf86a0623b923553a5f0e794daac7724f1e2fdbfb830` |
| `StablecoinHandler` | 8 | `0x185ed207c4d64fc594882ab927f9f3c6ff957aad03df8a731ba64378faeeb2bf` |
| `CctpExtensions` | 8 | `0x194c593691aed72b23b967cacad967a93c0b17ff98180d417e91ac503ce3597d` |

#### State object IDs

| Object | Object ID |
| :- | :- |
| `MessageTransmitterV2` | `0x0c067f7d325e5b60e3179712e7783534ba1556cbb3d359d8161497e37689230c` |
| `TokenMessengerMinterV2` | `0x06fb166941cd7bc095edc019d054a753ec3f1e4c25f28f2ecc4a6cfa0a9b1167` |
| `StablecoinHandler` | `0xa32de8a6dd0178fb05f662929d55cddb69a25c26bde4b83f89e36d17ead94c41` |
| USDC Treasury | `0x57d6725e7a8b49a7b2a612f6bd66ab5f39fc95332ca48be421c3229d514a6de7` |

<Note>
  `CctpExtensions` has no state object ID on either network. Callers of
  `CctpExtensions` do not need to pass a state object argument.
</Note>

The Sui CCTP source code is
[available on GitHub](https://github.com/circlefin/sui-cctp/).