change_audio_speed

Adjust audio playback speed by applying a speed multiplier to audio files. Modify tempo for faster or slower listening without altering pitch.

Instructions

Change the playback speed of audio

Input Schema

TableJSON Schema

Name	Required	Description
`audio_url`	Yes	URL of the audio file to process
`speed_factor`	Yes	Speed multiplier (e.g., 1.5 for 1.5x speed, 0.75 for 0.75x speed)
`webhook_url`	No	URL for callback upon completion

Implementation Reference

src/index.ts:1078-1097 (handler)

The handler function that implements the core logic for the 'change_audio_speed' tool. It validates input parameters, makes a POST request to the '/audio_speed_changer' API endpoint with the provided audio_url, speed_factor, and optional webhook_url, and returns a response message including the task_id for status checking.

private async handleChangeAudioSpeed(args: any) {
  if (!args.audio_url || !args.speed_factor) {
    throw new McpError(ErrorCode.InvalidParams, "audio_url and speed_factor are required");
  }

  const response = await this.axiosInstance.post("/audio_speed_changer", {
    audio_url: args.audio_url,
    speed_factor: args.speed_factor,
    webhook_url: args.webhook_url,
  });

  return {
    content: [
      {
        type: "text",
        text: `Audio speed change started!\n\n${JSON.stringify(response.data, null, 2)}\n\nUse get_conversion_by_id with the task_id to check the status.`,
      },
    ],
  };
}

src/index.ts:386-403 (schema)

Input schema defining the parameters for the 'change_audio_speed' tool: required audio_url (string) and speed_factor (number), optional webhook_url (string). Used for validation and tool description.

inputSchema: {
  type: "object" as const,
  properties: {
    audio_url: {
      type: "string",
      description: "URL of the audio file to process",
    },
    speed_factor: {
      type: "number",
      description: "Speed multiplier (e.g., 1.5 for 1.5x speed, 0.75 for 0.75x speed)",
    },
    webhook_url: {
      type: "string",
      description: "URL for callback upon completion",
    },
  },
  required: ["audio_url", "speed_factor"],
},

src/index.ts:383-404 (registration)

Tool registration entry in the TOOLS array, which is returned by the ListTools handler. Includes name, description, and input schema.

{
  name: "change_audio_speed",
  description: "Change the playback speed of audio",
  inputSchema: {
    type: "object" as const,
    properties: {
      audio_url: {
        type: "string",
        description: "URL of the audio file to process",
      },
      speed_factor: {
        type: "number",
        description: "Speed multiplier (e.g., 1.5 for 1.5x speed, 0.75 for 0.75x speed)",
      },
      webhook_url: {
        type: "string",
        description: "URL for callback upon completion",
      },
    },
    required: ["audio_url", "speed_factor"],
  },
},

src/index.ts:699-700 (registration)
Switch case in the CallToolRequestSchema handler that routes calls to 'change_audio_speed' to the specific handleChangeAudioSpeed method.
```
case "change_audio_speed":
  return await this.handleChangeAudioSpeed(args);
```

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