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

# Lyrics Infill

> Fill or rewrite a span of lyrics without generating music

Write or rewrite one span of lyrics. This calls the official lyrics-infill endpoint and returns that body in the **same response**. It does not create a clip, and it does not change [Generate Lyrics](/api-reference/suno/lyrics) or [Generate Music](/api-reference/suno/generate).

<Info>
  **Synchronous.** The lyrics are in this response. **No `taskId`** — do not poll [Get Task Status](/api-reference/suno/task).
</Info>

## Parameters

| Field | Required | Notes |
| - | - | - |
| `prompt` | Yes | What to write or how to change the span. Example: `a hopeful chorus about coming home` |
| `context_lyrics_prefix` | No | Lyrics before the span. Omit and the server sends `""` |
| `context_lyrics_edit` | No | The span being rewritten. Omit and the server sends `""` |
| `context_lyrics_suffix` | No | Lyrics after the span. Omit and the server sends `""` |
| `title` | No | Song title. Omit and the server sends `""` |

## Example

```bash theme={null}
curl -X POST https://api.mountsea.ai/suno/v2/lyricsInfill \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer your-api-key" \
  -d '{
    "prompt": "a hopeful chorus about coming home",
    "title": "Home",
    "context_lyrics_prefix": "[Verse]\nPacked the car before the sun",
    "context_lyrics_edit": "[Chorus]\n",
    "context_lyrics_suffix": "[Verse]\nHighway lines until they blur"
  }'
```


## OpenAPI

````yaml POST /suno/v2/lyricsInfill
openapi: 3.0.0
info:
  title: Suno AI
  description: API documentation for Suno AI
  version: 1.0.0
  contact: {}
servers:
  - url: https://api.mountsea.ai
    description: API Gateway
security: []
tags:
  - name: suno
    description: ''
  - name: suno/studio
    description: Studio Song Editor（与 audio/crop|fade|reverse 独立）
paths:
  /suno/v2/lyricsInfill:
    post:
      tags:
        - suno
      summary: lyrics infill
      description: >-
        Sync lyrics fill. Calls official POST /api/generate/lyrics-infill/ and
        returns that body. prompt is required. context_lyrics_prefix,
        context_lyrics_edit, context_lyrics_suffix and title are optional;
        omitted fields are sent as empty strings. This does not create music and
        does not change POST /lyrics or POST /generate.
      operationId: ApiPublicController_lyricsInfill
      parameters: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/LyricsInfillDto'
      responses:
        '201':
          description: ''
          content:
            application/json:
              schema:
                type: object
      security:
        - bearerAuth: []
components:
  schemas:
    LyricsInfillDto:
      type: object
      properties:
        prompt:
          type: string
          description: Instruction for the lyrics to write or fill in.
          example: a hopeful chorus about coming home
        context_lyrics_prefix:
          type: string
          description: Lyrics before the edit. Omitted values are sent as an empty string.
        context_lyrics_edit:
          type: string
          description: >-
            Lyrics currently selected for edit. Omitted values are sent as an
            empty string.
        context_lyrics_suffix:
          type: string
          description: Lyrics after the edit. Omitted values are sent as an empty string.
        title:
          type: string
          description: Song title. Omitted values are sent as an empty string.
      required:
        - prompt
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT

````

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