# Lyria 3.5 - Core.Today AI API

> Google's latest Lyria 3.5 music generation model via fal.ai. Generates full-length songs up to a few minutes with vocals and lyrics; control length and structure with duration hints or section timestamps in the prompt. Supports English, German, Spanish, French, Hindi, Japanese, Korean and Portuguese. Returns an MP3 file.

- **Provider**: Google
- **Model ID**: google/lyria-3.5
- **Category**: Audio & TTS
- **Credits**: 230 per song
- **Speed**: Medium
- **Quality**: Ultra

## Features
- Newest Lyria generation — full-length songs up to a few minutes
- Length and structure control via duration hints or [0:00-0:30] section markers
- Vocals and lyrics in 8 languages including Korean and Japanese
- Optional image as mood inspiration
- Returns generated lyrics alongside the MP3

## Use Cases
- Korean-language songs for videos, ads and short-form content
- Structured songs with timed intro / verse / chorus sections
- Theme songs and full-length background music

## API Endpoint

Base URL: https://api.core.today/v1
Create Prediction: POST /predictions
Get Status: GET /predictions/{job_id}

## Authentication
Header: X-API-Key: YOUR_API_KEY

## Input Parameters

### Required
- **prompt**: string - Text prompt describing the music. Include genre, mood, instrumentation, tempo, vocals, and structure. Use duration hints ('a 2-minute track') or section markers like '[0:00-0:30] Intro' to control length and structure.

### Optional
- **image_url**: string - Optional image URL used as inspiration — the music matches the image's mood and theme

## Examples

### Core.Today company song
The same Korean company-song lyrics given to every music model — compare how each one sings them
```json
{
  "model": "google/lyria-3.5",
  "input": {
    "prompt": "밝고 경쾌한 K-pop 일렉트로팝 회사 징글, 128 BPM, 힘찬 여성 보컬과 남성 코러스, 신스 브래스와 펀치 있는 드럼. [0:00-0:10] Intro: 신스 브래스 훅. [0:10-0:35] Verse: '아침부터 AI, 커피보다 진해 / 코딩하다 보니 벌써 새벽 두 시네! / 안 되는 건 없어, 일단 만들어 봐 / 상상이 현실 되는 마법 같은 회사!'. [0:35-1:05] Chorus: '코어! 닷! 투데이! / 오늘의 상상이 내일의 기술로! / 코어! 닷! 투데이! / AI도 놀라는 우리의 아이디어!'. [1:05-1:25] Outro: '뚝딱뚝딱 만들고, 반짝반짝 빛내고! / 기술을 넘어 경험으로! / 코어닷투데이, Hey!'. 1분 25초 길이."
  }
}
```

### Structured two-minute pop song
Duration and structure hints in the prompt shape the whole song
```json
{
  "model": "google/lyria-3.5",
  "input": {
    "prompt": "An uplifting pop song with driving electric guitar, energetic drums, and a catchy chorus singing 'Rise up and shine today'. 120 BPM. Two minutes long with a verse-chorus-verse-chorus-bridge-chorus structure."
  }
}
```

### Korean ballad with timed sections
Korean lyrics with section markers — generated through the gateway
```json
{
  "model": "google/lyria-3.5",
  "input": {
    "prompt": "잔잔한 피아노 발라드, 72 BPM, 여성 보컬, 어쿠스틱 악기만. [0:00-0:15] Intro: 피아노 솔로. [0:15-0:50] Verse: '창가에 남은 빛이 너를 닮아'. [0:50-1:30] Chorus: '다시 부르면 돌아올까'. 1분 30초 길이."
  }
}
```

## Response Format
```json
{
  "job_id": "abc123",
  "status": "pending | processing | completed | failed",
  "result": "URL or data (when completed)"
}
```

## Usage Flow
1. POST /predictions with model and input -> receive job_id
2. GET /predictions/{job_id} -> poll until status is completed or failed
3. Result contains output URL(s)

## Tips
- State the target length ('a 2-minute track') — without it the model picks the length
- Section markers like '[0:30-1:00] Verse: ...' give the most control over structure and lyric placement
- Korean, Japanese and Hindi vocals are supported — write the lyrics in that language
- Negative prompts are not supported — describe what you want (e.g. 'acoustic instruments only') instead of what to avoid
- Served by fal.ai only (no Replicate route yet), so there is no cross-provider fallback