Initialize the Vault

Creates the per-mint program vault — the token account every escrow for that mint deposits into (see The Program Vault). Run this once per mint before the first two-party deposit. (The mediated deposit initializes the vault on demand, so it isn't required there.)

Program method — token_account_init

Derives the vault PDA, builds, signs (payer), and sends.

Parameter	Type	Required	Default	Description
payer	Keypair	yes	—	Pays the fee and the vault rent; the only signer.
mint	#to_s	yes	—	The mint the vault will hold.
token_program_id	String	no	Solace::Constants::TOKEN_PROGRAM_ID	Token program that owns the mint. Use TOKEN_2022_PROGRAM_ID for Token-2022 mints.

Plus the shared sign: / execute: controls and Solace::Transaction return — see Conventions.

tx = program.token_account_init(payer: fee_payer, mint: mint_address)
connection.wait_for_confirmed_signature { tx.signature }

Composer — ZarTrustlessEscrowTokenAccountInitComposer

Use the composer for a custom fee payer or to batch with other instructions. The vault address must be resolved first (the program method does this via get_vault_address).

Parameter	Type	Required	Default	Description
mint	#to_s	yes	—	The mint the vault holds.
program_token_account	#to_s	yes	—	The vault PDA — from get_vault_address.
fee_payer	#to_s · Keypair	yes	—	Pays fee + rent; writable signer.
program_id	#to_s	no	mainnet PROGRAM_ID	The escrow program id.
token_program_id	#to_s	no	legacy SPL Token	Token program that owns the mint.

vault, = program.get_vault_address(mint: mint_address)

composer = Solace::Composers::ZarTrustlessEscrowTokenAccountInitComposer.new(
  mint:                  mint_address,
  program_token_account: vault,
  fee_payer:             fee_payer.address
)

tx = Solace::TransactionComposer.new(connection:)
                                .add_instruction(composer)
                                .set_fee_payer(fee_payer)
                                .compose_transaction

tx.sign(fee_payer)
connection.send_transaction(tx.serialize)

Low-level instruction (advanced)

TokenAccountInitInstruction.build encodes the raw instruction. Account positions are indices into the compiled message's AccountContext (the composer resolves these with context.index_of(...)).

• Discriminator: [124, 4, 173, 7, 212, 208, 18, 239]
• Encodes (data): discriminator only — no arguments.
• Accounts (in order): mint (writable) · program_token_account (writable) · fee_payer (writable signer) · system_program · token_program.

Parameter	Type	Required	Description
mint_index	Integer	yes	Index of the mint.
program_token_account_index	Integer	yes	Index of the vault.
fee_payer_index	Integer	yes	Index of the fee payer.
system_program_index	Integer	yes	Index of the System program.
token_program_index	Integer	yes	Index of the token program.
program_index	Integer	yes	Index of the escrow program (the invoked program).