PY-PYDA0004 · redundant_model_validate

Find model_validate calls that already spell out ordinary constructor fields.

This is a deterministic rule for python. Read its implementation.

Definition

Report Model.model_validate only when its sole argument is a dictionary literal or a keyword-only dict call with nonempty identifier keys and no validation options. In this shape the code already knows every field and Model(field=value) states that intent more directly. Keep model_validate at boundaries that receive an existing mapping, decoded document, ORM object, plugin payload, or caller-selected validation options.

Evidence

Each finding identifies the call and every explicit input key. The rule does not infer model schemas, aliases, or data produced at runtime. The value is the number of model_validate calls carrying one literal mapping.

Exceptions

Mapping variables, dictionary unpacking, non-identifier aliases, from_attributes, strictness, context, and other validation options are excluded. Tests are excluded because literal mappings there often exercise decoded configuration and invalid input boundaries. A thin from_table method may reasonably call cls.model_validate(table) because the mapping itself is the boundary.

Examples

Bad

`User.model_validate({"name": name, "age": age})` repeats an ordinary constructor shape.

Good

User(name=name, age=age) constructs explicit application values. User.model_validate(row) validates an existing external mapping and remains appropriate.

References

• Cites “Pydantic documentation”, models and model validation methods. Open reference
• Cites “Pydantic documentation”, aliases and mapping validation. Open reference