# Create segments

Creates a segment in the source's current segment version. A new text, OCR, or image description segment can be provided by source content.

```text
POST https://moi.matrixorigin.cn/newmoi/semantic-models/{model_id}/sources/{source_row_id}/segments
```

## Preparation before calling

First [query the document details](get-document.md), and obtain the current segment version ID and index version as the baseline. Prepare a personal access token and target workspace ID that has access to the target workspace.

The example below uses:

- `$AI_STUDIO_API_KEY`: The actual personal access token, passed through the `X-API-Key` Header.
- `$WORKSPACE_ID`: Target workspace ID, passed through `X-Workspace-ID` Header.
- `$MODEL_ID`: Knowledge Base ID.
- `$SOURCE_ROW_ID`: Source record ID.

## Request example

```bash
curl -X POST "https://moi.matrixorigin.cn/newmoi/semantic-models/$MODEL_ID/sources/$SOURCE_ROW_ID/segments" \
  -H "X-API-Key: $AI_STUDIO_API_KEY" \
  -H "X-Workspace-ID: $WORKSPACE_ID" \
  -H 'Content-Type: application/json' \
  -d '{
    "base_segment_version_id": "<SEGMENT_VERSION_ID>",
    "base_index_version": <INDEX_VERSION>,
    "level": "chunk",
    "content": "<SEGMENT_CONTENT>"
  }'
```

## Path parameters

| Parameters | Type | Description |
| --- | --- | --- |
| `model_id` | integer | Knowledge base ID. |
| `source_row_id` | string | Source record ID. |

## Request body

Commit source's current version baseline and staging content.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `base_segment_version_id` | string | Yes | The current segment version ID read before the call. |
| `base_index_version` | integer | Yes | The current index version read before the call. |
| `level` | string | No | Segment level. |
| `content` | string | No | Text segment content. |
| `ocr_text` | string | No | OCR recognized text. |
| `image_description` | string | No | Image content description. |
| `image_file_id` | string | No | The associated image file ID. |
| `page_image_file_id` | string | No | The associated page image file ID. |
| `bbox` | JSON | No | Boundary information for the segment in the original content. |
| `metadata` | JSON | No | Additional metadata. |

## Successful response

Returns `200` and the updated source document snapshot on success.

```json
{
  "code": "OK",
  "msg": "OK",
  "data": {
    "document": {
      "source": {
        "row_id": "src_01",
        "model_id": 401
      },
      "segment_status": {
        "available": true,
        "total": 3
      },
      "segment_versions": [
        {
          "version_id": "ver_03",
          "current": true,
          "chunk_count": 3
        }
      ],
      "segments": [
        {
          "segment_id": "seg_03",
          "segment_type": "text",
          "level": "chunk",
          "content": "新增分段",
          "enabled": true
        }
      ]
    }
  }
}
```

The response fields are as follows.

| Field | Type | Description |
| --- | --- | --- |
| `code` | string | `OK` on success. |
| `msg` | string | `OK` on success. |
| `data.document` | object | Snapshot of the source document after writing. |
| `data.document.source.row_id` | string | Source record ID. |
| `data.document.segment_status` | object | Current segment availability status and total number. |
| `data.document.segment_versions[].version_id` | string | New or updated segment version ID. |
| `data.document.segment_versions[].current` | boolean | Whether it is the current segmented version. |
| `data.document.segments[].segment_id` | string | New segment ID. |
| `data.document.segments[].level` | string | Segment level. |
| `data.document.segments[].content` | string | Segmented text; may be omitted if content is not returned. |
| `data.document.segments[].enabled` | boolean | Whether the segment participates in retrieval. |

In field paths, `[]` means each item in an array. For example, `data.document.segment_versions[].version_id` is the `version_id` field of each item in `data.document.segment_versions`.

## Error response

```json
{
  "code": "ErrParamInvalid",
  "msg": "invalid segment version baseline",
  "data": null
}
```

### Common HTTP errors

```{list-table}
:header-rows: 1
:widths: 12 22 32 34

* - HTTP status code
  - error code
  - Common causes
  - Recommended actions
* - `400`
  - `ErrParamInvalid`
  - The path ID, request body, or staging version baseline is invalid.
  - Submit using the current version information after re-reading the document.
* - `401`
  - `ErrUnauthorized`
  - The API Key is invalid or has expired.
  - Check API Key.
* - `403`
  - `ErrForbidden`
  - The caller does not have permission to update this source.
  - Check workspace and object authorization.
* - `404`
  - `ErrNotFound`
  - The knowledge base or source does not exist or is not visible to the current caller.
  - Reread source list to confirm ID.
* - `409`
  - `ErrConflict`
  - The current version has changed and the service refuses to write.
  - Merge changes after reading the latest document and try again.
* - `500`
  - `ErrServer`
  - The service failed to create the segment.
  - Keep the desensitized response information and try again.
```

## Follow-up operations

[Query document details](get-document.md) confirms that the new segment has taken effect.