# Compose music

Source: https://recoupable.dev/docs/api-reference/complete/content/post-music-compose

Generate a song from a text prompt or a composition plan. The prompt can describe mood, genre, instruments, lyrics, and structure. Alternatively, pass a full composition_plan for fine-grained control over sections, styles, and lyrics. Returns binary audio in the requested format (default MP3).

## POST /api/music/compose

Full OpenAPI specification: https://recoupable.dev/docs/spec/content.json

## Authentication

This operation requires one of the security alternatives in the specification below. Security scheme definitions are included where present in the published specification.

[Authentication guide](https://recoupable.dev/docs/authentication)

## Operation and referenced schemas

```json
{
  "openapi": "3.1.0",
  "info": {
    "title": "Recoup API - Content",
    "description": "API documentation for the Recoup platform - an AI agent platform for the music industry",
    "license": {
      "name": "MIT"
    },
    "version": "1.0.0"
  },
  "servers": [
    {
      "url": "https://api.recoupable.dev"
    }
  ],
  "paths": {
    "/api/music/compose": {
      "post": {
        "description": "Generate a song from a text prompt or a composition plan. The prompt can describe mood, genre, instruments, lyrics, and structure. Alternatively, pass a full composition_plan for fine-grained control over sections, styles, and lyrics. Returns binary audio in the requested format (default MP3).",
        "security": [
          {
            "apiKeyAuth": []
          },
          {
            "bearerAuth": []
          }
        ],
        "requestBody": {
          "description": "Music composition parameters",
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "$ref": "#/components/schemas/MusicComposeRequest"
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Audio generated successfully",
            "headers": {
              "song-id": {
                "schema": {
                  "type": "string"
                },
                "description": "Unique identifier for the generated song"
              }
            },
            "content": {
              "audio/mpeg": {
                "schema": {
                  "type": "string",
                  "format": "binary"
                }
              }
            }
          },
          "400": {
            "description": "Validation failed — invalid or missing request body fields",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/MusicErrorResponse"
                }
              }
            }
          },
          "401": {
            "description": "Unauthorized — invalid or missing API key",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/MusicErrorResponse"
                }
              }
            }
          },
          "500": {
            "description": "Internal server error",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/MusicErrorResponse"
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "MusicComposeRequest": {
        "type": "object",
        "description": "Parameters for generating a song. Provide either a text prompt or a composition_plan.",
        "properties": {
          "prompt": {
            "type": "string",
            "description": "Text prompt describing the desired song — mood, genre, instruments, lyrics, structure."
          },
          "composition_plan": {
            "type": "object",
            "description": "Full composition plan for fine-grained control over sections, styles, and lyrics. Use POST /api/music/plan to generate one."
          },
          "duration": {
            "type": "number",
            "description": "Desired duration in seconds.",
            "default": 30
          },
          "output_format": {
            "type": "string",
            "description": "Audio output format (e.g. mp3_44100_192).",
            "default": "mp3_44100_192"
          },
          "sign_with_c2pa": {
            "type": "boolean",
            "description": "Sign the output with C2PA content credentials.",
            "default": false
          }
        }
      },
      "MusicErrorResponse": {
        "type": "object",
        "required": [
          "error"
        ],
        "description": "Error response from a music endpoint.",
        "properties": {
          "error": {
            "type": "string",
            "description": "Error message describing what went wrong."
          }
        }
      }
    },
    "securitySchemes": {
      "apiKeyAuth": {
        "type": "apiKey",
        "in": "header",
        "name": "x-api-key",
        "description": "Your Recoup API key. [Learn more](/quickstart#api-keys)."
      },
      "bearerAuth": {
        "type": "http",
        "scheme": "bearer"
      }
    }
  }
}
```