trading_agent.risk.trading_limits ¶

Reads the hard limits from the fenced ```toml limits block of TradingRules.md.

The file is read before every order, so an accepted change to the rules takes effect on the next order. A file without the block, or with a block that is not valid, makes the risk engine refuse every order that is not closing a position: when the limits cannot be known, the safe answer is no.

Typical usage example:

limits = TradingLimitsReader(Path('workspace/shared/TradingRules.md')).read() limits.account.daily_loss_limit_percent

LimitsError ¶

Bases: ValueError

TradingRules.md has no readable limits block.

AccountLimits ¶

Bases: BaseModel

The limits for the whole account, shared by every desk.

Attributes:

Name	Type	Description
`trading_enabled`	`bool`	Whether any desk may open or enlarge a position.
`capital_percent`	`float`	The share of the total balance the agent may commit as margin.
`daily_loss_limit_percent`	`float`	Today's loss, as a share of the live total balance, that stops every desk and closes every position.
`weekly_loss_limit_percent`	`float`	This week's loss, as a share of the live total balance, that stops every desk until Monday.
`maximum_order_value_percent`	`float`	The largest margin one order may block, as a share of the live total balance.
`maximum_open_positions`	`int \| None`	The most instruments that may be held at once, or None for no cap.
`trading_window`	`str`	"exchange_hours" for each exchange's own session, or "HH:MM-HH:MM" in India time for every exchange.
`allow_option_writing`	`bool`	Whether a desk may sell options to open or enlarge a short position.

DeskLimits ¶

Bases: BaseModel

The limits for one desk, on top of the account's.

Attributes:

Name	Type	Description
`capital_share_percent`	`float \| None`	The desk's share of the agent's capital, or None to draw on the shared pool.
`allowed_products`	`list[str]`	The products the desk may use, such as mis, cnc or nrml; empty allows all.
`allowed_instruments`	`list[str]`	The symbols the desk may trade; empty allows all.
`maximum_orders_per_minute`	`int \| None`	How many orders the desk may send in a minute, or None for no cap.
`daily_loss_limit_percent`	`float \| None`	Today's loss on the instruments this desk owned, as a share of the live total balance, that stops this desk alone for the rest of the day; None for no desk limit.

TradingLimits ¶

Bases: BaseModel

Everything in the limits block.

Attributes:

Name	Type	Description
`account`	`AccountLimits`	The account-wide limits.
`desks`	`dict[str, DeskLimits]`	The per-desk limits, keyed by desk name; a desk without an entry has no extra limits.

desk ¶

desk(desk_name)

The limits of one desk.

Parameters:

Name	Type	Description	Default
`desk_name`	`str`	The desk.	required

Returns:

Type	Description
`DeskLimits`	Its limits, or limits that add nothing when the desk has no entry.

Source code in src/trading_agent/risk/trading_limits.py

def desk(self, desk_name: str) -> DeskLimits:
    """The limits of one desk.

    Args:
        desk_name (str): The desk.

    Returns:
        DeskLimits: Its limits, or limits that add nothing when the desk has no entry.
    """
    return self.desks.get(desk_name, DeskLimits())

TradingLimitsReader ¶

TradingLimitsReader(rules_file)

Reads the limits block from one TradingRules.md.

Remembers which file to read.

Parameters:

Name	Type	Description	Default
`rules_file`	`Path`	The TradingRules.md file.	required

Source code in src/trading_agent/risk/trading_limits.py

def __init__(self, rules_file: Path):
    """Remembers which file to read.

    Args:
        rules_file (Path): The TradingRules.md file.
    """
    self._rules_file = rules_file

read ¶

read()

Reads and checks the limits block.

Returns:

Type	Description
`TradingLimits`	The limits.

Raises:

Type	Description
`LimitsError`	The file is missing, has no limits block, or the block is not valid TOML with valid values.

Source code in src/trading_agent/risk/trading_limits.py

def read(self) -> TradingLimits:
    """Reads and checks the limits block.

    Returns:
        TradingLimits: The limits.

    Raises:
        LimitsError: The file is missing, has no limits block, or the block is not valid TOML with valid values.
    """
    try:
        text = self._rules_file.read_text(encoding='utf-8')
    except FileNotFoundError as error:
        raise LimitsError(f'{self._rules_file} does not exist') from error
    match = _LIMITS_BLOCK.search(text)
    if match is None:
        raise LimitsError(
            f'{self._rules_file.name} has no ```toml limits block'
        )
    try:
        parsed = tomllib.loads(match.group(1))
        return TradingLimits.model_validate(parsed)
    except (tomllib.TOMLDecodeError, pydantic.ValidationError) as error:
        raise LimitsError(
            f'The limits block in {self._rules_file.name} is not valid: {error}'
        ) from error