Google Flow Music API (Lyria 3.5 and Lyria 3 Pro) examples by useapi.net

Runnable Node.js examples for the Google Flow Music API by useapi.net, a Lyria API for full songs: generate with Google's Lyria 3.5 or Lyria 3 Pro (vocals or instrumental, your own custom lyrics, plus cover / remix / extend / replace / stems editing), with a hosted MCP server of 18 tools. It all runs through a simple REST API that drives your own Flow Music account, at roughly 6–10× less per song than Google's official $0.08-a-song Lyria 3 Pro API.

Each example reads a list of prompts from prompts.json, submits them through the useapi.net Flow Music API, and downloads every finished track.

| Example | What it does | Tutorial | |---|---|---| | lyria-music/ | Batch-generate full songs with Lyria 3.5 or Lyria 3 Pro (per-prompt model) — vocals or instrumental, custom lyrics, async polling | How to Generate AI Music with Lyria 3 Pro via the Flow Music API |

Quick start

You need Node.js v21 or newer (no dependencies to install), a useapi.net API token, and a connected Flow Music account (one $15/month subscription covers every useapi.net API):

git clone https://github.com/useapi/flowmusic-api.git
cd flowmusic-api/lyria-music
node ./flowmusic.mjs <API_TOKEN> <EMAIL>

Edit prompts.json in each folder to queue your own prompts. Every supported parameter is documented on the POST /music and music/edit endpoint pages.

MCP server

useapi.net also runs a hosted Model Context Protocol server for Flow Music, so an AI assistant such as Claude Code, Cursor or VS Code Copilot can use it on your own account. It has 18 tools: songs with Lyria from a description, your own lyrics or lyrics the model writes; extend, replace a section, cover, remix lyrics, audio effects and stems; reference uploads; credits and jobs. Nothing to install or run locally.

• Endpoint: https://api.useapi.net/v1/flowmusic/mcp
• Transport: Streamable HTTP
• Authorization: your useapi.net API token in the Authorization: Bearer … header, and an account connected with the Flow Music setup
• Listed in the official MCP Registry as net.useapi/flowmusic

Claude Code:

claude mcp add --transport http useapi-flowmusic https://api.useapi.net/v1/flowmusic/mcp --header "Authorization: Bearer YOUR_API_TOKEN"

Cursor, VS Code, Windsurf and the full tool list: Flow Music MCP server docs. useapi.net is a third-party API, not affiliated with Google.

Use with Claude Code

This repo is also a Claude Code plugin marketplace. The plugin adds the hosted Flow Music MCP server, and reads your token from the USEAPI_TOKEN environment variable, so set it before you start Claude Code:

export USEAPI_TOKEN=user:12345-...      # your useapi.net API token

Then, inside Claude Code:

/plugin marketplace add useapi/flowmusic-api
/plugin install flowmusic@useapi-flowmusic

On Claude Code 2.1.275 or later, /plugin install flowmusic --marketplace useapi/flowmusic-api does both in one step. Run /mcp to check that useapi-flowmusic is connected.

Use with Gemini CLI

This repo is also a Gemini CLI extension with the same MCP server:

gemini extensions install https://github.com/useapi/flowmusic-api

The install asks for your useapi.net API token and keeps it in the system keychain. Change it later with gemini extensions config useapi-flowmusic, and check the connection with gemini mcp list.

Common questions

<!-- Official API figures in these answers, verified 2026-10-18: https://ai.google.dev/gemini-api/docs/pricing (Lyria 3.5 / 3 Pro $0.08 per song). Plan figures: useapi.net/docs/api-flowmusic-v1 calculator. -->

• Is there a Google Flow Music API? Yes, through useapi.net: a third-party REST API that drives your own Flow Music account (Google Labs' music app, formerly Producer AI and originally Riffusion) with a useapi.net token, so you generate at your Flow Music plan's prices: a full Lyria 3.5 song costs about $0.008 to $0.013 on a paid plan, against $0.08 per song on Google's Gemini API (as of October 2026). Google has no public Flow Music API.
• Is there a Lyria 3.5 API? Yes. Pass model: "lyria-3.5" (Google's current flagship) or lyria-3-pro (the default) to POST /music and POST /music/edit. The lyria-music/ example takes it per prompt.
• How is this different from Google's official Lyria API? This API needs only a useapi.net token and your Flow Music account, costs about $0.008–$0.013 per song on paid Flow Music plans against $0.08 on Google's official Lyria API (as of October 2026), and adds cover, remix, extend, replace, audio effects and stem splitting. Google's official Lyria 3 Pro API needs your own Google Cloud project and API key.
• Where do I get an API key? You call this API with a useapi.net API token and connect your Flow Music account once through the Flow Music setup: the automated setup signs you in with Google in a remote browser, with no DevTools or token copying. No Google Cloud project is needed.
• How much does it cost? A flat $15/month to useapi.net, which covers every useapi.net API, plus your Flow Music plan: Starter $8/month (about 600 songs), Plus $24/month (about 2,000) or Member $64/month (about 6,000), about 25% less yearly. That is about $0.008–$0.013 a song, against $0.08 on Google's Gemini API (as of October 2026). The free plan gets daily top-up credits. Downloads (mp3, wav, m4a and stems) are free. See the cost calculator.
• Is it a Suno / Udio alternative? Yes. Like Suno and Udio, it writes and sings a full song with vocals from one text prompt, up to about 3 minutes (5+ with extend), and returns up to two clips per generation.
• More answers: Flow Music API questions.

About useapi.net

useapi.net is an experimental REST API for AI services. The Flow Music API drives your own Flow Music account, so you generate at consumer-plan credit prices (about 6–10× cheaper per song than Google's official Lyria 3 Pro API) instead of metered developer pricing. See the model matrix and pricing on the API overview.

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License

The example code in this repository is released under the MIT License. It covers the example scripts only, not the useapi.net service or API.