create-taxonomy-python

create-taxonomy-python

Taxonomy = stable domain language. Single source of truth for VOs, entities, errors, events, constants. Location: modules/shared/src/<domain>/.

Allowed imports: other taxonomy types, stdlib. Forbidden: capabilities, agents, surface, root, contracts, I/O (in VOs/entities/errors/events/constants).

File Types

Suffix	Content	Key constraint
_vo.py	Value Objects	Validate in__init__, immutable, no I/O
_entity.py	Entities with identity	Identity VO field required
_error.py	Domain errors	ExtendException, VO fields only
_event.py	Domain events	Immutable, VO payload fields
_constant.py	Compile-time constants	Pure literals only — no functions, no I/O
_utility.py	Stateless helpers	No class, noself, domain-agnostic

VO Rules (AES401/AES402)

Forbidden for domain fields: str, int, float, list[str], dict. bool allowed for semantic toggles only.

Templates

Value Object

from dataclasses import dataclass


@dataclass(frozen=True)
class <Name>:
    _value: str

    def __post_init__(self) -> None:
        if not self._value.strip():
            raise ValueError("<Name> cannot be empty")

    @property
    def value(self) -> str:
        return self._value

    def __str__(self) -> str:
        return self._value

Entity

from dataclasses import dataclass


@dataclass(frozen=True)
class <Name>:
    _value: str

    def __post_init__(self) -> None:
        if not self._value.strip():
            raise ValueError("<Name> cannot be empty")

    @property
    def value(self) -> str:
        return self._value

    def __str__(self) -> str:
        return self._value

Error

class <Name>Error(Exception):
    def __init__(self, message: str):
        self._message = message
        super().__init__(message)

    @property
    def message(self) -> str:
        return self._message