Instruction Discriminators

Every instruction in the PerpetualInstruction enum is encoded using Borsh.

The first byte of serialized data is the enum variant index, also called the instruction discriminator.

This byte determines which instruction the program executes.

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How It Works

When serialized:

<u8 discriminator> + <borsh-encoded fields>

Example:

Buffer.concat([
  Buffer.from([7]),   // TradeFutures discriminator
  ...encodedFields
])

The Rust side resolves it via:

pub fn discriminator(&self) -> u8 {
    match self {
        Self::Deposit { .. } => 0,
        ...
    }
}

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Complete Discriminator Table

User Balance Management (0–2)

Discriminator	Instruction
0	Deposit
1	Withdraw
2	WithdrawTo

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Order Management (3–8)

Discriminator	Instruction
3	OpenLimit
4	CloseLimit
5	CancelLimit
6	MatchOrder
7	TradeFutures
8	ClosePosition

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Conditional Orders (9–11)

Discriminator	Instruction
9	PlaceConditionalOrder
10	CancelConditionalOrder
11	PlaceBracketOrder

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Triggers & Execution (12–14)

Discriminator	Instruction
12	TriggerOrders
13	TriggerOpenOrder
14	TriggerCloseOrder

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Liquidation (15–18)

Discriminator	Instruction
15	ClearingTaker
16	LiquidateMakerDeal
17	LiquidateMakerDeals
18	AfterLiquidateTaker

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Public Pool Operations (19–21)

Discriminator	Instruction
19	InitializePublicPool
20	AddPublicLiquidity
21	WithdrawPublicLiquidity

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Private Pool Operations (22–24)

Discriminator	Instruction
22	InitializePrivatePool
23	AddPrivateLiquidity
24	WithdrawPrivateLiquidity

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Pool Management (25–27)

Discriminator	Instruction
25	MoveToPublic
26	AddMarginAmount
27	SetUserParam

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Pool CPI (Internal) (28–29)

Discriminator	Instruction
28	PoolMatchOrder
29	PoolCloseOrder

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Admin Functions (30–39)

Discriminator	Instruction
30	SetUnderlying
31	SetKeepers
32	SetTradeFeeAddr
33	SetMaintenanceMarginRate
34	SetTradeFeeRate
35	SetLimitFeeRate
36	SetStartStop
37	SetPoolPublishAppendRate
38	InitializeConfig
39	InitializeUserAccount

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View Functions (42–47)

Discriminator	Instruction
42	GetAccountInfo
43	GetPosition
44	GetOrder
45	GetLimitedOrder
46	GetPNLByCertainPosition
47	CheckTakerRiskStatus

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Important Notes

• Discriminators must match Rust enum ordering exactly.
• Changing enum order will break compatibility.
• Always hardcode discriminator values in frontend builders.
• Never rely on implicit enum ordering in TypeScript.

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Example: Manual Encoding

const data = Buffer.concat([
  Buffer.from([0]), // Deposit
  writeU128LE("1000000000000000000")
]);

const data = Buffer.concat([
  Buffer.from([7]), // TradeFutures
  ...encodedFields
]);

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Validation Rule

Before decoding:

pub fn validate_instruction_data(data: &[u8]) -> Result<(), ProgramError> {
    if data.is_empty() {
        return Err(InstructionUnpackError.into());
    }
    Ok(())
}

The first byte determines the variant.

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This table is the canonical reference for all client-side instruction builders.