Audiobook generation - Typecast Documentation

Audiobook workflows benefit from repeatable naming, stable voice settings, and chapter-level files. The CLI gives an agent a simple command surface for generating drafts, rerendering chapters, and keeping approved audio separate.

Prepare defaults

Set the voice and model once before generating chapters:

cast config set voice-id tc_xxx
cast config set model ssfm-v30
cast config set format mp3

If you need a project-specific voice, clone it first and store the returned uc_ voice ID:

cast voices clone narrator-sample.wav --name "Narrator Draft"
cast config set voice-id uc_xxx

Generate chapters

cast "$(cat chapter-01.txt)" \
  --emotion smart \
  --out audiobook/chapter-01.mp3 \
  --format mp3

cast "$(cat chapter-02.txt)" \
  --emotion smart \
  --out audiobook/chapter-02.mp3 \
  --format mp3

Generate captions or review timing

cast "$(cat chapter-01.txt)" \
  --emotion smart \
  --out audiobook/chapter-01.wav \
  --timestamps-out audiobook/chapter-01.timestamps.json

Use JSON for detailed review timing, or write .srt / .vtt when the audiobook content also needs a video preview.

Use emotion for scene changes

For short passages with a known tone, preset emotion can be more controllable than smart emotion:

cast "The room fell silent as the letter slipped from her hand." \
  --emotion preset \
  --emotion-preset sad \
  --emotion-intensity 1.2 \
  --out audiobook/scene-letter.mp3

For passages where surrounding context matters, pass neighboring text:

cast "She opened the door and froze." \
  --emotion smart \
  --prev-text "The hallway had been empty a moment ago." \
  --next-text "A familiar voice whispered her name." \
  --out audiobook/scene-door.mp3

Agent prompt pattern

Generate audiobook draft files from the chapter text files.
Use the same voice for every chapter.
Write output to ./audiobook.
Use one MP3 per chapter.
For chapters that also need video previews, generate an SRT file next to the audio.
If a chapter fails, report the filename and keep going.

File naming

Asset	Suggested filename
Full chapter	`chapter-01.mp3`
Scene revision	`chapter-01-scene-03-v2.mp3`
Approved final	`chapter-01-final.mp3`
Alternate delivery	`chapter-01-alt-happy.mp3`

When to use advanced features

Need	Recommended feature
Consistent narrator identity	`cast config set voice-id ...`
Temporary narrator matching a sample	`cast voices clone narrator-sample.wav --name "Narrator Draft"`
Chapter review timing	`--timestamps-out chapter-01.timestamps.json`
Video preview for a chapter	`--timestamps-out chapter-01.srt`
Quick approval playback	`cast "one review sentence"` without `--out`

Avoid overwriting approved audio. Ask the agent to write revisions with -v2, -v3, or a delivery label.

​Prepare defaults

​Generate chapters

​Generate captions or review timing

​Use emotion for scene changes

​Agent prompt pattern

​File naming

​When to use advanced features

Prepare defaults

Generate chapters

Generate captions or review timing

Use emotion for scene changes

Agent prompt pattern

File naming

When to use advanced features