---
title: "update_storyboard_sound: Update a sound card"
description: "Change one sound card, addressed by its number in the answer's sounds array or by id: where it starts, its source window, length or gain."
canonical_url: "https://meetkuro.com/agents/tools/update_storyboard_sound/"
updated: 2026-11-03
locale: "en"
tool: "update_storyboard_sound"
scopes: ["storyboards.write"]
---

# update_storyboard_sound

**Update a sound card**

Change one sound card, addressed by its number in the answer's sounds array or by id: where it starts, its source window, length or gain. A null from_scene opens that end of its span. One undo step; undo_storyboard takes it back. Spends no credits.

## Scope

- `storyboards.write` — Authors, edits, renders and deletes storyboards. Reading a board rides media.read, and the two board tools that spend need generation.write as well.

## Behaviour

- **Writes**: Creates or changes items in the caller's own account.
- **Can delete or overwrite**: Can delete, overwrite, cancel or withdraw something the caller already has, so a host should confirm it.
- **Stays in the account**: Stays inside the caller's private Kuro account: any media provider it calls acts on Kuro's account, and the result is visible to no one else.

## Credits

What the tool's description says about credits, verbatim:

- Spends no credits.

## Inputs

| Name | Type | Required | Details |
| --- | --- | --- | --- |
| `storyboard_id` | string | yes | uuid |
| `sound` | integer or string | yes | — |
| `changes` | object | yes | fields: from_scene, start_offset_seconds, source_in_seconds, source_out_seconds, loop_duration_seconds, length, gain_db |

## Example call

A `tools/call` request with the required arguments only, each a placeholder read off the schema. Replace them before sending.

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "update_storyboard_sound",
    "arguments": {
      "storyboard_id": "00000000-0000-4000-8000-000000000000",
      "sound": 1,
      "changes": {}
    }
  }
}
```

## Input schema

As the server sends it in `tools/list`:

```json
{
  "type": "object",
  "properties": {
    "storyboard_id": {
      "type": "string",
      "format": "uuid"
    },
    "sound": {
      "anyOf": [
        {
          "type": "integer",
          "exclusiveMinimum": 0
        },
        {
          "type": "string",
          "format": "uuid"
        }
      ]
    },
    "changes": {
      "type": "object",
      "properties": {
        "from_scene": {
          "anyOf": [
            {
              "$ref": "#/properties/sound/anyOf/0"
            },
            {
              "type": "null"
            }
          ]
        },
        "start_offset_seconds": {
          "type": "number",
          "minimum": 0
        },
        "source_in_seconds": {
          "type": "number",
          "minimum": 0
        },
        "source_out_seconds": {
          "anyOf": [
            {
              "type": "number",
              "exclusiveMinimum": 0
            },
            {
              "type": "null"
            }
          ]
        },
        "loop_duration_seconds": {
          "anyOf": [
            {
              "type": "number",
              "exclusiveMinimum": 0
            },
            {
              "type": "null"
            }
          ]
        },
        "length": {
          "type": "string",
          "enum": [
            "loop",
            "once",
            "in_full"
          ]
        },
        "gain_db": {
          "type": "integer",
          "minimum": -40,
          "maximum": 0
        }
      },
      "additionalProperties": false
    }
  },
  "required": [
    "storyboard_id",
    "sound",
    "changes"
  ],
  "additionalProperties": false
}
```

## Related tools

- [`undo_storyboard`](https://meetkuro.com/agents/tools/undo_storyboard.md): Take back YOUR last gesture on a film, or redo the one you took back.

---

## About Kuro

Kuro is an AI picture studio: prompt-driven images, clips, voice-overs and music, and storyboard-backed films with consistent characters across every scene.

Agents connect over MCP and can generate directly:

```
claude mcp add kuro https://api.meetkuro.com/mcp --transport http
```

The app is at https://app.meetkuro.com and requires an account.

Each guide, model page, comparison and free tool page on this site (not a tool's variants, and not the index pages) has a Markdown twin at its own URL plus `.md`, and so do /benchmarks/, the English /agents/ page (as /agents.md) and the MCP tool reference. Every tool: https://meetkuro.com/agents/tools/