# RunManagerMixin

> **Class** in `langchain_core`

📖 [View in docs](https://reference.langchain.com/python/langchain-core/callbacks/base/RunManagerMixin)

Mixin for run manager.

## Signature

```python
RunManagerMixin()
```

## Methods

- [`on_text()`](https://reference.langchain.com/python/langchain-core/callbacks/base/RunManagerMixin/on_text)
- [`on_retry()`](https://reference.langchain.com/python/langchain-core/callbacks/base/RunManagerMixin/on_retry)
- [`on_custom_event()`](https://reference.langchain.com/python/langchain-core/callbacks/base/RunManagerMixin/on_custom_event)

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[View source on GitHub](https://github.com/langchain-ai/langchain/blob/f0c5a28fa05adcda89aebcb449d897245ab21fa4/libs/core/langchain_core/callbacks/base.py#L394)