> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ragrails.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Chunking

> Split CLI extraction JSON into retrieval-ready chunks.

`ragrails chunk` reads extraction output JSON from `--input-dir` and writes `chunks.json` to `--output-dir`.

Use it when you want to inspect or version chunks before embedding. If you do not need intermediate files, use `ragrails ingest` instead.

## Command

```bash theme={null}
ragrails chunk \
  --input-dir files/output/docs/ \
  --output-dir files/output/chunks/ \
  --chunk-size 2000 \
  --chunk-overlap 200 \
  --min-chunk-length 100
```

Output:

```text theme={null}
Documents : 12
Chunks    : 87
Failed    : 0
Saved to  : files/output/chunks/chunks.json
```

## Choosing Chunk Size

Start at `--chunk-size 2000` with `--chunk-overlap 200`. Lower the size for dense factual content like FAQs, specs, or policies. Raise it when answers need more surrounding context.

## Options

| Option               | Default  | Description                                     |
| -------------------- | -------- | ----------------------------------------------- |
| `--input-dir`        | required | Folder containing extraction output JSON files. |
| `--output-dir`       | required | Folder to write `chunks.json`.                  |
| `--chunk-size`       | `2000`   | Target max characters per chunk.                |
| `--chunk-overlap`    | `200`    | Character overlap between adjacent chunks.      |
| `--min-chunk-length` | `100`    | Drop chunks shorter than this.                  |

## Next Stage

```bash theme={null}
ragrails embed --input-dir files/output/chunks/ --output-dir files/output/embedded/
```

<CardGroup cols={2}>
  <Card title="Extraction" icon="file-input" href="/usage/cli/extraction">Create document JSON.</Card>
  <Card title="Embedding" icon="binary" href="/usage/cli/embedding">Embed chunk JSON.</Card>
</CardGroup>