SKILL.md
Install the belt CLI skill: npx skills add belt-sh/cli
AI Voice Generation
Generate natural AI voices via inference.sh CLI.
Quick Start
Requires inference.sh CLI (belt). Install instructions
belt loginGenerate speech
belt app run infsh/kokoro-tts --input '{
"prompt": "Hello! This is an AI-generated voice that sounds natural and engaging.",
"voice": "af_sarah"
}'
## Available Models
| Model | App ID | Best For |
|-------|--------|----------|
| **Inworld TTS-2** | `inworld/text-to-speech-2` | **100+ languages, emotion/non-verbal steering, delivery modes** |
| Inworld TTS 1.5 Max | `inworld/text-to-speech-1-5-max` | Low latency (<200ms), 15 languages |
| Inworld TTS 1.5 Mini | `inworld/text-to-speech-1-5-mini` | Ultra-low latency (~120ms), 15 languages, real-time |
| ElevenLabs TTS | `elevenlabs/tts` | Premium quality, 22+ voices, 32 languages |
| ElevenLabs Voice Changer | `elevenlabs/voice-changer` | Transform existing voice recordings |
| Kokoro TTS | `infsh/kokoro-tts` | Natural, multiple voices |
| DIA | `infsh/dia-tts` | Conversational, expressive |
| Chatterbox | `infsh/chatterbox` | Casual, entertainment |
| Higgs | `infsh/higgs-tts` | Professional narration |
| VibeVoice | `infsh/vibevoice` | Emotional range |
## Kokoro Voice Library
### American English
| Voice ID | Gender | Style |
|----------|--------|-------|
| `af_sarah` | Female | Warm, friendly |
| `af_nicole` | Female | Professional |
| `af_sky` | Female | Youthful |
| `am_michael` | Male | Authoritative |
| `am_adam` | Male | Conversational |
| `am_echo` | Male | Clear, neutral |
### British English
| Voice ID | Gender | Style |
|----------|--------|-------|
| `bf_emma` | Female | Refined |
| `bf_isabella` | Female | Warm |
| `bm_george` | Male | Classic |
| `bm_lewis` | Male | Modern |
## Inworld TTS — Character & Emotion Voices
Inworld TTS-2 is purpose-built for character voices, gaming, and expressive speech. Use `[brackets]` inline for emotion, non-verbals, and delivery control:
Expressive character voice with emotion steering
belt app run inworld/text-to-speech-2 --input '{
"text": "[excited] Oh wow, you actually found the ancient artifact! [gasp] I cannot believe it... [whisper] We need to keep this between us.",
"voice_id": "Sarah",
"delivery_mode": "CREATIVE"
}'
Calm narrator with stable delivery
belt app run inworld/text-to-speech-2 --input '{
"text": "The sun set behind the mountains, casting long shadows across the valley. A new chapter was about to begin.",
"voice_id": "Sarah",
"delivery_mode": "STABLE"
}'
**Delivery modes:** `STABLE` (consistent, narration), `BALANCED` (natural, default), `CREATIVE` (expressive, characters)
**Steering examples:** `[laugh]`, `[sigh]`, `[whisper]`, `[excited]`, `[sad]`, `[angry]`, `[pause]`, `[gasp]`
**Built-in voices** (271+ across 15 languages): `Sarah`, `Alex`, `Ashley`, `Dennis`, `Hana`, `Blake`, `Luna`, `Clive`, and many more. Browse all at the [Inworld TTS Playground](https://platform.inworld.ai/tts-playground).
### Low-Latency for Real-Time / Conversational AI
Ultra-fast response for chatbots & game NPCs (~120ms)
belt app run inworld/text-to-speech-1-5-mini --input '{
"text": "Welcome, traveler. What brings you to our village?",
"voice_id": "Clive",
"speaking_rate": 0.9
}'
## Voice Generation Examples
### Professional Narration
belt app run infsh/kokoro-tts --input '{
"prompt": "Welcome to our quarterly earnings call. Today we will discuss the financial performance and strategic initiatives for the past quarter.",
"voice": "am_michael",
"speed": 1.0
}'
### Conversational Style
belt app run infsh/dia-tts --input '{
"text": "Hey, so I was thinking about that project we discussed. What if we tried a different approach?",
"voice": "conversational"
}'
### Audiobook Narration
belt app run infsh/kokoro-tts --input '{
"prompt": "Chapter One. The morning mist hung low over the valley as Sarah made her way down the winding path. She had been walking for hours.",
"voice": "bf_emma",
"speed": 0.9
}'
### Video Voiceover
belt app run infsh/kokoro-tts --input '{
"prompt": "Introducing the next generation of productivity. Work smarter, not harder.",
"voice": "af_nicole",
"speed": 1.1
}'
### Podcast Host
belt app run infsh/kokoro-tts --input '{
"prompt": "Welcome back to Tech Talk! Im your host, and today we are diving deep into the world of artificial intelligence.",
"voice": "am_adam"
}'
## Multi-Voice Conversation
Generate dialogue between two speakers
Speaker 1
belt app run infsh/kokoro-tts --input '{
"prompt": "Have you seen the latest AI developments? Its incredible how fast things are moving.",
"voice": "am_michael"
}' > speaker1.json
Speaker 2
belt app run infsh/kokoro-tts --input '{
"prompt": "I know, right? Just last week I tried that new image generator and was blown away.",
"voice": "af_sarah"
}' > speaker2.json
Merge conversation
belt app run infsh/media-merger --input '{
"audio_files": ["<speaker1-url>", "<speaker2-url>"],
"crossfade_ms": 300
}'
## Long-Form Content
### Chunked Processing
For content over 5000 characters, split into chunks:
Process long text in chunks
TEXT="Your very long text here..."
Split and generate
Chunk 1
belt app run infsh/kokoro-tts --input '{
"prompt": "<chunk-1>",
"voice": "bf_emma"
}' > chunk1.json
Chunk 2
belt app run infsh/kokoro-tts --input '{
"prompt": "<chunk-2>",
"voice": "bf_emma"
}' > chunk2.json
Merge chunks
belt app run infsh/media-merger --input '{
"audio_files": ["<chunk1-url>", "<chunk2-url>"],
"crossfade_ms": 100
}'
## Voice + Video Workflow
### Add Voiceover to Video
1. Generate voiceover
belt app run infsh/kokoro-tts --input '{
"prompt": "This stunning footage shows the beauty of nature in its purest form.",
"voice": "am_michael"
}' > voiceover.json
2. Merge with video
belt app run infsh/media-merger --input '{
"video_url": "https://your-video.mp4",
"audio_url": "<voiceover-url>"
}'
### Create Talking Head
1. Generate speech
belt app run infsh/kokoro-tts --input '{
"prompt": "Hi, Im excited to share some updates with you today.",
"voice": "af_sarah"
}' > speech.json
2. Animate with avatar
belt app run bytedance/omnihuman-1-5 --input '{
"image_url": "https://portrait.jpg",
"audio_url": "<speech-url>"
}'
## Speed and Pacing
Speed
Effect
Use For
0.8
Slow, deliberate
Audiobooks, meditation
0.9
Slightly slow
Education, tutorials
1.0
Normal
General purpose
1.1
Slightly fast
Commercials, energy
1.2
Fast
Quick announcements
Slow narration
belt app run infsh/kokoro-tts --input '{
"prompt": "Take a deep breath. Let yourself relax.",
"voice": "bf_emma",
"speed": 0.8
}'
## Punctuation for Pacing
Use punctuation to control speech rhythm:
Punctuation
Effect
Period `.`
Full pause
Comma `,`
Brief pause
`...`
Extended pause
`!`
Emphasis
`?`
Question intonation
`-`
Quick break
belt app run infsh/kokoro-tts --input '{
"prompt": "Wait... Did you hear that? Something is coming. Something big!",
"voice": "am_adam"
}'
## Best Practices
- **Match voice to content** - Professional voice for business, casual for social
- **Use punctuation** - Control pacing with periods and commas
- **Keep sentences short** - Easier to generate and sounds more natural
- **Test different voices** - Same text sounds different across voices
- **Adjust speed** - Slightly slower often sounds more natural
- **Break long content** - Process in chunks for consistency
## Use Cases
- **Voiceovers** - Video narration, commercials
- **Audiobooks** - Full book narration
- **Podcasts** - AI hosts and guests
- **E-learning** - Course narration
- **Accessibility** - Screen reader content
- **IVR** - Phone system messages
- **Content localization** - Translate and voice
## Related Skills
ElevenLabs TTS (premium, 22+ voices)
npx skills add inference-sh/skills@elevenlabs-tts
ElevenLabs voice changer (transform recordings)
npx skills add inference-sh/skills@elevenlabs-voice-changer
All TTS models
npx skills add inference-sh/skills@text-to-speech
Podcast creation
npx skills add inference-sh/skills@ai-podcast-creation
AI avatars
npx skills add inference-sh/skills@ai-avatar-video
Video generation
npx skills add inference-sh/skills@ai-video-generation
Full platform skill
npx skills add inference-sh/skills@infsh-cli