Instruction: QuoteSend

This instruction returns a quote of the fees needed to send a cross-chain message.

Input parameters

• dst_eid: This is the identifier of the remote endpoint.

• receiver: This is the address of the receiver contract.

• message: This is the arbitrary string to be sent to the remote contract.

• options: These are the send options; these are used in addition to the enforced options specified in the OApp configuration for the given receiver.

• pay_in_lz_token: If this is false, the fee is calculated in native currency; otherwise, it is calculated using the LayerZero token.

Accounts

The instruction receives the following accounts explicitly:

• store: Account storing the global OApp configuration.

  • PDA: Yes, with seed STORE_SEED.

• peer: Account representing an allowlisted remote contract.

  • PDA: Yes, with seeds PEER_SEED, store.key(), and params.dst_eid.

• endpoint: Account storing the settings for the LayerZero endpoint on Solana.

  • PDA: Yes, with seed ENDPOINT_SEED, derived from the endpoint program ID.

It also forwards the remaining accounts in the CPI made to get the messaging fee from the LayerZero endpoint.

CPI

The LayerZero endpoint is invoked to get a quote for the messaging fees.

The accounts for the CPI are forwarded verbatim from the Anchor context remaining_accounts, and the caller is responsible for providing the correct ones.

The QuoteParams struct providing arguments for the instruction is initialized as follows:

• sender: ctx.accounts.store.key().

• dst_eid: params.dst_eid.

• receiver: params.receiver.

• message: params.message encoded by prepending the string length (32 bytes) before the UTF-8 representation of the string.

• pay_in_lz_token: params.pay_in_lz_token.

• options: params.options combined with the enforced options configured in the per-peer configuration.