# MapReduceChain

> **Class** in `langchain_classic`

📖 [View in docs](https://reference.langchain.com/python/langchain-classic/chains/mapreduce/MapReduceChain)

Map-reduce chain.

## Signature

```python
MapReduceChain()
```

## Extends

- `Chain`

## Properties

- `combine_documents_chain`
- `text_splitter`
- `input_key`
- `output_key`
- `model_config`
- `input_keys`
- `output_keys`

## Methods

- [`from_params()`](https://reference.langchain.com/python/langchain-classic/chains/mapreduce/MapReduceChain/from_params)

## ⚠️ Deprecated

Deprecated since version 0.2.13. Use langchain.agents.create_agent instead. Will be removed in version 2.0.0. For map-reduce branching, build a LangGraph using the Send API. See https://docs.langchain.com/oss/python/langgraph/use-graph-api#map-reduce-and-the-send-api

---

[View source on GitHub](https://github.com/langchain-ai/langchain/blob/42f8f79293cfb7589e5bc1d74a8ae4dfd0bf15e3/libs/langchain/langchain_classic/chains/mapreduce.py#L30)