Policy Condition Language (PCL)

This page provides an overview of how to write conditions for Swivell's Policy Engine.

Language Features

Primitives

Type	Description	Examples
string	Text values enclosed in single or double quotes	`'mainnet'`, `'BTC'`, `"0x123..."`
bool	True/false values	`true`, `false`
float	Numeric values with decimals	`100.0`, `0.5`, `1000.50`
list	Collections of values	`['mainnet', 'arbitrum']`, `[1, 2, 3]`
object	Structured data with named fields	`{ symbol: "USD0" }`, `{ address: "0x123...", risk_score: 0.3 }`

Comparisons

Equality and Inequality

== - Equal to: deposit.amount == 100.0
!= - Not equal to: deposit.network != 'mainnet'

Numeric Comparisons

< - Less than: deposit.value_usd < 1000.0
> - Greater than: deposit.amount > 50.0
<= - Less than or equal: deposit.value_usd <= 5000.0
>= - Greater than or equal: deposit.amount >= 10.0

Logical Operators

&& - Logical AND: deposit.amount > 0 && deposit.value_usd < 1000.0
|| - Logical OR: deposit.network == 'mainnet' || deposit.network == 'arbitrum'
! - Logical NOT: !deposit.asset.is_possible_spam

Membership

in - Check if value exists in list: deposit.network in ['mainnet', 'arbitrum']

Objects

Field Access

. - Access object properties: deposit.asset.symbol

Lists

Access Elements

[index] - Get element at index: deposit.originators[0]

Functions

size() - Get list length: size(deposit.originators)
.all(item, condition) - Check if all items match: deposit.originators.all(o, o.risk_score < 0.5)
.exists(item, condition) - Check if any item matches: deposit.originators.exists(o, o.risk_score > 0.8)

Context

The policy conditions have these variables in scope

Keyword	Type	Description	Available On
`deposit`	Deposit	The deposit being processed	`effect_freeze`, `effect_forward`

`Deposit` Object

Field	Type	Description
`id`	string	Unique identifier for the deposit
`network`	string	Network where the deposit occurred (e.g mainnet, solana, base, arbitrum)
`asset`	Asset	Details about the deposited asset
`amount`	float	Amount of tokens deposited
`value_usd`	float	USD value of the deposit (optional)
`originators`	list[Originator]	The originators of the deposit

`Asset` Object

Field	Type	Description
`address_checksum`	string	The address/mint of the token in case-sensitive format
`address_lowercase`	string	The address/mint of the token in lowercase format
`symbol`	string	The symbol for the token (e.g., "BTC", "ETH")
`network`	string	The network the token is on (e.g mainnet, solana, base, arbitrum)
`is_possible_spam`	bool	Whether the token is flagged as possible spam
`name`	string	The full name of the token (optional)
`pegged_to`	string	Symbol this token's price is pegged to (optional)

`Originator` Structure

Field	Type	Description
`address_checksum`	string	The address of the originator in case-sensitive format
`address_lowercase`	string	The address of the originator in lowercase format
`risk_score`	float	Score of the originator's fraud risk

Examples Conditions

Amount Limits

// Allow deposits under $1,000 USD
deposit.value_usd < 1000.0

// Limit token amount
deposit.amount <= 100.0

Asset Restrictions

// Only allow specific tokens
deposit.asset.symbol in ['BTC', 'ETH', 'USDC']

// Block spam tokens
!deposit.asset.is_possible_spam

// Check specific token address (case-sensitive)
deposit.asset.address_checksum == '0xA0b86a33E6441d8178E82c5A3f4fa6Afdd59E33e'

// Check address (case-insensitive)
deposit.asset.address_lowercase == '0xa0b86a33e6441d8178e82c5a3f4fa6afdd59e33e'

Network Controls

// Only allow Ethereum mainnet
deposit.network == 'mainnet'

// Allow multiple networks
deposit.network in ['mainnet', 'arbitrum', 'base']

Combined Conditions

// Mainnet deposits under $10k OR L2 deposits under $5k
(deposit.network == 'mainnet' && deposit.value_usd < 10000.0) ||
(deposit.network in ['arbitrum', 'base'] && deposit.value_usd < 5000.0)

// Safe assets only
deposit.asset.symbol in ['ETH', 'USDC'] && !deposit.asset.is_possible_spam

Stablecoin Handling

// USD-pegged tokens with higher limits
deposit.asset.pegged_to == 'USD' && deposit.value_usd < 25000.0

// Specific stablecoins
!deposit.is_possible_spam && deposit.asset.symbol in ['USDC', 'USDT', 'DAI']

Originator Risk Validation

// Block high-risk originators
deposit.originators.all(o, o.risk_score < 0.5)

// Allow deposits if any originator has low risk
deposit.originators.exists(o, o.risk_score < 0.2)

// Check specific originator addresses (case-sensitive)
deposit.originators.exists(o, o.address_checksum in trusted_addresses)

// Check originator addresses (case-insensitive)
deposit.originators.exists(o, o.address_lowercase in trusted_addresses_lower)