Interactive Contract Playground

Test LayerZero contracts directly from your browser. No coding required. Explore key application functions for message fee calculation, sending, receiving, configuration, and state management. This page focuses on methods relevant to building applications and does not include worker-related functions.

Real On-Chain Methods

All functions shown in this playground are real methods available in the LayerZero contracts today:

• Endpoint Contract: Source Code
• OFT Contract: Source Code

We only document OApp-relevant instructions, excluding admin-only functions. State variables are clearly marked as direct account data reads, not instructions.

LayerZero EndpointV2

The main entry point for all cross-chain messaging operations. This contract handles message routing, fee calculation, and configuration management.

Message Routing

Core functions for sending and receiving messages between smart contracts.

quote() - Get Fee Estimates

CALL

0x0fbd277fquote(_params: MessagingParams, _sender: address)

send() - Send Messages

SEND

0x1fd91580send(_params: MessagingParams, _refundAddress: address)

lzReceive() - Receive Messages

SEND

0xbb68813elzReceive(_origin: Origin, _receiver: address, _guid: bytes32, _message: bytes, _extraData: bytes)

sendCompose() - Send Compose Messages

SEND

0x7cb59012sendCompose(_to: address, _guid: bytes32, _index: uint16, _message: bytes)

lzCompose() - Execute Compose Messages

SEND

0x91d20fa1lzCompose(_from: address, _to: address, _guid: bytes32, _index: uint16, _message: bytes, _extraData: bytes)

Configuration Management

Functions for setting custom verification, execution, and pathway management.

eid() - Get Endpoint ID

CALL

0x416ecebfeid()

isRegisteredLibrary() - Check Library Registration

CALL

0xdc706a62isRegisteredLibrary(lib: address)

receiveLibraryTimeout() - Get Library Timeout

CALL

0xef667aa1receiveLibraryTimeout(receiver: address, srcEid: uint32)

setDelegate() - Set Delegate Address

SEND

0xca5eb5e1setDelegate(_delegate: address)

setSendLibrary() - Configure Send Library

SEND

0x9535ff30setSendLibrary(_oapp: address, _eid: uint32, _newLib: address)

setReceiveLibrary() - Configure Receive Library

SEND

0x6a14d715setReceiveLibrary(_oapp: address, _eid: uint32, _newLib: address, _gracePeriod: uint256)

setConfig() - Set Configuration Parameters

SEND

0x01dd9320setConfig(_oapp: address, _lib: address, _params: SetConfigParam[])

Message Recovery & Security

Functions for handling message exceptions, security threats, and recovery scenarios.

clear() - Clear Stored Message

SEND

0x841515b1clear(_oapp: address, _origin: Origin, _guid: bytes32, _message: bytes)

burn() - Permanently Block Message

SEND

0x40f80683burn(_oapp: address, _srcEid: uint32, _sender: bytes32, _nonce: uint64, _payloadHash: bytes32)

skip() - Skip Message Nonce

SEND

0xd70b8902skip(_oapp: address, _srcEid: uint32, _sender: bytes32, _nonce: uint64)

nilify() - Mark Message as Nil

SEND

0x2e80fbf3nilify(_oapp: address, _srcEid: uint32, _sender: bytes32, _nonce: uint64, _payloadHash: bytes32)

Status Checks

Functions for querying current configuration settings, library assignments, nonce tracking, and message states.

getConfig() - Check Configuration

CALL

0x2b3197b9getConfig(_oapp: address, _lib: address, _eid: uint32, _configType: uint32)

delegates() - Check Delegate Address

CALL

0x587cde1edelegates(oapp: address)

getSendLibrary() - Get Send Library

CALL

0xb96a277fgetSendLibrary(_sender: address, _dstEid: uint32)

getReceiveLibrary() - Get Receive Library

CALL

0x402f8468getReceiveLibrary(_receiver: address, _srcEid: uint32)

inboundNonce() - Get Processed Nonce

CALL

0xa0dd43fcinboundNonce(_receiver: address, _srcEid: uint32, _sender: bytes32)

lazyInboundNonce() - Get Lazy Nonce

CALL

0x5b17bb70lazyInboundNonce(receiver: address, srcEid: uint32, sender: bytes32)

initializable() - Check Message Initialization

CALL

0x8a237427initializable(_origin: Origin, _receiver: address)

verifiable() - Check Message Verification

CALL

0xbe619818verifiable(_origin: Origin, _receiver: address)

inboundPayloadHash() - Get Message Payload Hash

CALL

0xc9fc7bcdinboundPayloadHash(receiver: address, srcEid: uint32, sender: bytes32, inboundNonce: uint64)

nextGuid() - Get Next Message GUID

CALL

0xaafe5e07nextGuid(_sender: address, _dstEid: uint32, _receiver: bytes32)

composeQueue() - Check Compose Message Queue

CALL

0x35d330b0composeQueue(from: address, to: address, guid: bytes32, index: uint16)

isSendingMessage() - Check Send State

CALL

0x79624ca9isSendingMessage()

getSendContext() - Get Current Send Context

CALL

0x14f651a9getSendContext()

Events

Key events emitted by the EndpointV2 contract.

PacketSent - Message Sent Event

EVENT

PacketSent(bytes encodedPayload, bytes options, address sendLibrary)

PacketVerified - Message Verified Event

EVENT

PacketVerified(tuple origin, address receiver, bytes32 payloadHash)

PacketDelivered - Message Delivered Event

EVENT

PacketDelivered(tuple origin, address receiver)

ComposeSent - Compose Message Queued Event

EVENT

ComposeSent(address from, address to, bytes32 guid, uint16 index, bytes message)

ComposeDelivered - Compose Message Delivered Event

EVENT

ComposeDelivered(address from, address to, bytes32 guid, uint16 index)

DelegateSet - Delegate Configuration Event

EVENT

DelegateSet(address sender, address delegate)

SendLibrarySet - Send Library Configuration Event

EVENT

SendLibrarySet(address sender, uint32 eid, address newLib)

ReceiveLibrarySet - Receive Library Configuration Event

EVENT

ReceiveLibrarySet(address receiver, uint32 eid, address newLib)

ReceiveLibraryTimeoutSet - Library Timeout Configuration Event

EVENT

ReceiveLibraryTimeoutSet(address receiver, uint32 eid, address oldLib, uint256 timeout)

InboundNonceSkipped - Nonce Skip Event

EVENT

InboundNonceSkipped(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce)

PacketNilified - Message Nilified Event

EVENT

PacketNilified(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash)

PacketBurnt - Message Burnt Event

EVENT

PacketBurnt(uint32 srcEid, bytes32 sender, address receiver, uint64 nonce, bytes32 payloadHash)

Errors

LZ_InsufficientFee - Insufficient Fee

ERROR

0x4f3ec0d3

LZ_InsufficientFee(uint256 requiredNative, uint256 suppliedNative, uint256 requiredLzToken, uint256 suppliedLzToken)

LZ_InvalidNonce - Invalid Nonce

ERROR

0xc09b6350

LZ_InvalidNonce(uint64 nonce)

LZ_Unauthorized - Unauthorized Access

ERROR

0xc4c52593

LZ_Unauthorized()

LZ_SendReentrancy - Send Reentrancy Detected

ERROR

0xee120b09

LZ_SendReentrancy()

Key Functions to Try:

• Messaging Operations:
  • quote() - Get fee estimates for cross-chain messages
  • send() - Send messages to other chains
  • lzReceive() - Receive messages from other chains
  • sendCompose() - Queue compose messages
  • lzCompose() - Execute compose messages
• Configuration Management:
  • setDelegate() - Assign configuration permissions
  • setSendLibrary() - Choose send message library
  • setReceiveLibrary() - Choose receive message library
  • setConfig() - Set library-specific parameters
• Message Recovery & Security:
  • burn() - Permanently block malicious messages
  • skip() - Skip flagged message nonces
  • nilify() - Mark messages for re-verification
  • clear() - Clear verified but unexecuted messages
• Status Checks:
  • getConfig() - Check current configurations
  • delegates() - View current delegate address
  • getSendLibrary() - Check send library for endpoint
  • getReceiveLibrary() - Check receive library for endpoint
  • inboundNonce() - Get highest processed message nonce
  • lazyInboundNonce() - Get highest verified/skipped nonce
  • nextGuid() - Get next message GUID
  • composeQueue() - Check compose queue
  • isSendingMessage() - Check send state
  • getSendContext() - Get send context

Omnichain Application (OApp)

The foundation for building any cross-chain application. OApp provides the core messaging infrastructure for a smart contract interacting with the EndpointV2.

Core Information

oAppVersion() - Get OApp Version

CALL

0x17442b70oAppVersion()

endpoint() - Get Endpoint Address

CALL

0x5e280f11endpoint()

Peer Configuration

peers() - Get Remote Peer Address

CALL

0xbb0b6a53peers(eid: uint32)

setPeer() - Connect Remote Chains

SEND

0x3400288bsetPeer(_eid: uint32, _peer: bytes32)

setDelegate() - Set Configuration Delegate

SEND

0xca5eb5e1setDelegate(_delegate: address)

Message Reception

allowInitializePath() - Check Path Initialization

CALL

0xbfe94e81allowInitializePath(origin: Origin)

nextNonce() - Get Next Message Nonce

CALL

0x7d25a05enextNonce(: uint32, : bytes32)

lzReceive() - Receive Cross-Chain Messages

SEND

0xbf282d99lzReceive(_origin: Origin, _guid: bytes32, _message: bytes, _executor: address, _extraData: bytes)

Composability

isComposeMsgSender() - Verify Compose Sender

CALL

0x8833c245isComposeMsgSender(: Origin, : bytes, _sender: address)

Events and Errors

Key events and errors emitted by the OApp contract.

Events

PeerSet - Peer Configuration Updated

EVENT

PeerSet(uint32 eid, bytes32 peer)

Errors

OnlyPeer - Unauthorized Peer Message

ERROR

0xc26bebcc

OnlyPeer(uint32 eid, bytes32 sender)

NoPeer - Missing Peer Configuration

ERROR

0xf6ff4fb7

NoPeer(uint32 eid)

InvalidEndpointCall - Invalid Endpoint Call

ERROR

0x0fbdec0a

InvalidEndpointCall()

InvalidDelegate - Invalid Delegate Configuration

ERROR

0xb5863604

InvalidDelegate()

NotEnoughNative - Insufficient Native Fee

ERROR

0x9f704120

NotEnoughNative(uint256 msgValue)

OnlyEndpoint - Unauthorized Endpoint Call

ERROR

0x91ac5e4f

OnlyEndpoint(address addr)

LzTokenUnavailable - LayerZero Token Not Available

ERROR

0x5373352a

LzTokenUnavailable()

Key Functions to Try:

• Core Information:
  • oAppVersion() - Get OApp version information
  • endpoint() - Get connected endpoint address
• Peer Configuration:
  • setPeer() - Connect to remote chains
  • peers() - Check connected chains
  • setDelegate() - Set configuration delegate
• Message Reception:
  • lzReceive() - Receive cross-chain messages
  • allowInitializePath() - Check path initialization
  • nextNonce() - Get message ordering info
• Composability:
  • isComposeMsgSender() - Verify compose sender

Tips:

• Peers must be set before messaging
• Nonces ensure ordered delivery
• Options control execution parameters

Omnichain Application Read (OAppRead)

OAppRead extends the standard OApp with LayerZero Read functionality, enabling cross-chain data reading capabilities. It includes all standard methods plus the read channel configuration.

setReadChannel() - Configure Read Channel

SEND

0xf0a9e481setReadChannel(_channelId: uint32, _active: bool)

Key Functions to Try:

• setReadChannel() - Configure read channel for cross-chain data reading
• Plus all standard OApp functions listed above

Omnichain Fungible Token (OFT)

OFT inherits from OApp, providing all cross-chain messaging capabilities plus token-specific functionality. Create tokens that work seamlessly across multiple blockchains while maintaining a unified supply.

Send Tokens

quoteSend() - Get Transfer Fees

CALL

0x2f603a24quoteSend(_sendParam: SendParam, _payInLzToken: bool)

quoteOFT() - Get Detailed Transfer Quote

CALL

0xe6343d44quoteOFT(_sendParam: SendParam)

send() - Transfer Tokens

SEND

0xccfc9451send(_sendParam: SendParam, _fee: MessagingFee, _refundAddress: address)

Token Details

sharedDecimals() - Get Shared Decimals

CALL

0x857749b0sharedDecimals()

approvalRequired() - Check Approval Requirement

CALL

0x9f68b964approvalRequired()

oftVersion() - Get OFT Version

CALL

0x156a0d0foftVersion()

token() - Get Underlying Token Address

CALL

0xfc0c546atoken()

decimalConversionRate() - Get Decimal Conversion Factor

CALL

0x963efcaadecimalConversionRate()

Management Functions

owner() - Get Current Owner

CALL

0x8da5cb5bowner()

transferOwnership() - Transfer Contract Ownership

SEND

0xf2fde38btransferOwnership(newOwner: address)

renounceOwnership() - Renounce Ownership

SEND

0x715018a6renounceOwnership()

setPeer() - Connect to Remote OFTs

SEND

0x3400288bsetPeer(_eid: uint32, _peer: bytes32)

setEnforcedOptions() - Configure Message Options

SEND

0xd833f371setEnforcedOptions(_enforcedOptions: EnforcedOptionParam[])

setMsgInspector() - Set Message Inspector

SEND

0x6fc1b31esetMsgInspector(_msgInspector: address)

Events

Key events emitted by the OFT contract.

OFTSent - Token Transfer Sent

EVENT

OFTSent(indexed bytes32 guid, uint32 dstEid, indexed address fromAddress, uint256 amountSentLD, uint256 amountReceivedLD)

OFTReceived - Token Transfer Received

EVENT

OFTReceived(indexed bytes32 guid, uint32 srcEid, indexed address toAddress, uint256 amountReceivedLD)

Transfer - Standard ERC20 Transfer

EVENT

Transfer(indexed address from, indexed address to, uint256 value)

Errors

InvalidLocalDecimals - Invalid Decimal Configuration

ERROR

0x1e9714b0

InvalidLocalDecimals()

SlippageExceeded - Transfer Slippage Too High

ERROR

0x71c4efed

SlippageExceeded(uint256 amountLD, uint256 minAmountLD)

AmountSDOverflowed - Shared Decimal Overflow

ERROR

0xe2ce9413

AmountSDOverflowed(uint256 amountSD)

Key Functions to Try:

• Transfer Operations:
  • quoteSend() - Get transfer fee estimates
  • send() - Transfer tokens cross-chain
  • quoteOFT() - Get comprehensive transfer quotes
• Token Information:
  • sharedDecimals() - Check decimal configuration
  • approvalRequired() - Check if approval is needed
  • oftVersion() - Get OFT implementation version
  • token() - Get underlying token address
  • decimalConversionRate() - Get decimal conversion factor
• Management Functions:
  • owner() - Check current contract owner
  • setPeer() - Connect to OFTs on other chains
  • setEnforcedOptions() - Configure security parameters
  • setMsgInspector() - Set message inspector
  • transferOwnership() - Transfer contract ownership
  • renounceOwnership() - Permanently remove ownership

Tips:

• Always call quoteSend() before send() to get accurate fees
• The minAmountLD parameter provides slippage protection
• Shared decimals (typically 6-8) may differ from local decimals (e.g., 18 for most ERC20s)
• approvalRequired() returns false for OFT and true for OFTAdapter
• Use quoteOFT() for detailed information including transfer limits and fee breakdowns
• OFTAdapter requires approval on the underlying token before sending
• Must call setPeer() to connect OFTs on different chains before transfers
• Only the contract owner can call management functions
• Use setEnforcedOptions() to enforce minimum gas limits for security
• renounceOwnership() is irreversible - use with extreme caution

For complete contract documentation including all functions, events, and technical details:

• Contract Standards Overview
• OApp Technical Reference
• OFT Technical Reference
• Protocol Contracts

info

Contract ABIs shown here are from the latest deployment. Always verify addresses and ABIs for your specific use case.