# Validate Call

Decorator for validating function calls.

## validate\_call

```python
def validate_call(
    *,
    config: ConfigDict | None = None,
    validate_return: bool = False,
) -> Callable[[AnyCallableT], AnyCallableT]
def validate_call(func: AnyCallableT, /) -> AnyCallableT
```

:::callout{intent="note" title="Usage Documentation"}
[Validation Decorator](/guides/concepts-validation-decorator)
:::

Returns a decorated wrapper around the function that validates the arguments and, optionally, the return value.

Usage may be either as a plain decorator `@validate_call` or with arguments `@validate_call(...)`.

When a decorated call fails, the [`ValidationError`](/guides/pydantic-core-pydantic-core#validationerror) names the rejected argument, but the traceback won’t show the value the caller passed. [Logfire](/guides/integrations-logfire) records failing calls along with their arguments — see [Troubleshooting validation errors](/guides/error-messages-troubleshooting).

### Returns

`AnyCallableT` | [`Callable`](https://docs.python.org/3/library/typing.html#typing.Callable)\[\[`AnyCallableT`], `AnyCallableT`] — The decorated function.

### Parameters

**`func`** : `AnyCallableT` | [`None`](https://docs.python.org/3/builtins/constants.html#None) _Default:_ `None`

The function to be decorated.

**`config`** : [`ConfigDict`](/guides/pydantic-config#configdict) | [`None`](https://docs.python.org/3/builtins/constants.html#None) _Default:_ `None`

The configuration dictionary.

**`validate_return`** : [`bool`](https://docs.python.org/3/builtins/functions.html#bool) _Default:_ `False`

Whether to validate the return value.

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## Related pages

- [API Documentation](./api-documentation-index.md)
- [Concepts](./concepts-index.md)
- [Dev Tools](./dev-tools-index.md)
- [Error Messages](./error-messages-index.md)
- [Examples](./examples-index.md)
- [Integrations](./integrations-index.md)
- [Internals](./internals-index.md)
- [Production Tools](./production-tools-index.md)
- [Pydantic](./pydantic-index.md)
- [Pydantic Core](./pydantic-core-index.md)

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