必须另行安装 ffmpeg,否则无法合成音视频;需在项目目录建 .env 并至少配置 OPENAI_API_KEY;使用 GPT Image 模型需先完成 OpenAI 组织验证
npm install -g mulmocast
brew install ffmpegREADME 未说明显存或 GPU 要求,生成依赖云端 AI API,本地只需能运行 Node.js 与 ffmpeg 的环境
用 JSON 脚本把文字素材生成播客、视频、幻灯片和漫画的 AI 多模态内容工具
用脚本把文字稿一键生成带配音、口型同步和幻灯片的播客或视频,省去剪辑和录音流程。
核心能力
- 用 MulmoScript JSON/YAML 描述说话人、文本、图像与布局
- 一条 mulmo movie 命令合成音频、图像并拼接成视频
- 支持视频、播客、幻灯片、PDF、漫画、滑动动画多种输出
- 内置交互式脚本生成,可从网页或本地文件取材
- 可切换 OpenAI、Gemini、Claude、Replicate、ElevenLabs 等模型供应商
容易踩的坑
Highlights
- Singing avatars: a beat's voice from a JingleScript score (#1657):
beat.audioaccepts{ "type": "jinglescript", "score": { … } }, rendered (and cached by hash) and used as the beat's voice instead of TTS. A track with"sing": { "engine": "neutrino" }is sung by your local NEUTRINO (NEUTRINO_DIR, default/Applications/NEUTRINO). The beat'stextstays the words, so captions and avatar lip sync follow the lyrics. - JingleScript 1.0 (#1657):
render()runs on a worker thread, so long renders and NEUTRINO vocals no longer block the process @mulmocast/types2.24.0: new beat audio schema, zod^4.6.7- LICENSE file (#1653): AGPL-3.0 text at the repository root (license unchanged)
- Dependency updates (#1654, #1663, #1655, #1656, #1658, #1660, #1662)
Sample: scripts/test/test_avatar_singing.json
📦 npm:
[email protected]
What's Changed
- release: 2.23.0 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1652
- chore: AGPL-3.0 の LICENSE ファイルを追加 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1653
- chore(deps): bump follow-redirects from 1.16.0 to 1.16.1 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1656
- chore(deps): bump hono from 4.13.7 to 4.13.13 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1655
- feat: jinglescript 1.0, and a beat's voice from a JingleScript score (singing avatars) by @snakajima in https://github.com/receptron/mulmocast-cli/pull/1657
- chore(deps): bump ip-address from 10.7.2 to 10.7.5 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1662
- update by @isamu in https://github.com/receptron/mulmocast-cli/pull/1654
- chore(deps): bump fast-uri from 3.1.8 to 3.1.9 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1660
- chore(deps): bump body-parser from 2.3.0 to 2.4.0 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1658
- update by @isamu in https://github.com/receptron/mulmocast-cli/pull/1663
Full Changelog: https://github.com/receptron/mulmocast-cli/compare/2.23.0...2.24.0
- Singing avatars: a beat's voice from a JingleScript score (#1657):
- @mulmocast/[email protected]2026-10-27 · 2026-10-27 05:40 UTC
查看更新说明
Highlights
- Beat audio from a JingleScript score (#1657):
mulmoAudioAssetSchemaaccepts{ type: "jinglescript", score } - zod
^4.6.7: same range asmulmocast, so the two packages share one zod
📦 npm:
@mulmocast/[email protected]
What's Changed
- release: @mulmocast/types 2.21.0 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1637
- chore: fail CI when types/ and the root disagree on a shared dependency by @isamu in https://github.com/receptron/mulmocast-cli/pull/1639
- feat(beat_html): draw backgrounds, slide branding and reference like the PNG render by @isamu in https://github.com/receptron/mulmocast-cli/pull/1642
- feat(beat_html): return html_tailwind scripts and animation as documentScript by @isamu in https://github.com/receptron/mulmocast-cli/pull/1643
- release: 2.22.0 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1644
- fix: skip the audio probe for still images so image-only renders do not need ffmpeg by @isamu in https://github.com/receptron/mulmocast-cli/pull/1646
- release: 2.22.1 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1647
- Update package20261015 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1648
- docs: add a user guide for talking avatars (AvatarScript) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1649
- fix: ask users for the avatarscript this repository is tested with (^0.5.0) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1651
- release: 2.23.0 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1652
- chore: AGPL-3.0 の LICENSE ファイルを追加 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1653
- chore(deps): bump follow-redirects from 1.16.0 to 1.16.1 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1656
- chore(deps): bump hono from 4.13.7 to 4.13.13 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1655
- feat: jinglescript 1.0, and a beat's voice from a JingleScript score (singing avatars) by @snakajima in https://github.com/receptron/mulmocast-cli/pull/1657
- chore(deps): bump ip-address from 10.7.2 to 10.7.5 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1662
- update by @isamu in https://github.com/receptron/mulmocast-cli/pull/1654
- chore(deps): bump fast-uri from 3.1.8 to 3.1.9 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1660
- chore(deps): bump body-parser from 2.3.0 to 2.4.0 by @dependabot[bot] in https://github.com/receptron/mulmocast-cli/pull/1658
- update by @isamu in https://github.com/receptron/mulmocast-cli/pull/1663
Full Changelog: https://github.com/receptron/mulmocast-cli/compare/@mulmocast/[email protected]...@mulmocast/[email protected]
- Beat audio from a JingleScript score (#1657):
查看更新说明
Highlights
- Avatars need avatarscript 0.5 (#1651, #1650): the
avatarscriptpeer range is now^0.5.0, the version this repository is built and tested with. It said^0.4.0, which excludes 0.5, sonpm install mulmocast avatarscript onnxruntime-nodeinstalled 0.4.1. Projects using avatars should upgrade:npm install avatarscript@^0.5.0. A new test fails whenever a devDependency's range falls outside the peer range users are told to install. - JingleScript 0.8 (#1648): recorded CC0 sound effects (
ding,glass,metal,punch,book,door,dice,cards,cloth, morefootsteps) usable insoundEffectsscores, and agrandpianothat plays like a piano (re-striking damps the ringing note,lenreleases the key, a sustainpedal). Scores usinggrandpianomay sound different. - Avatar guide (#1649):
docs/avatar.md— installing the optional packages, the five ready-made avatars, making your own with mesh-avatar-studio,avatarParams, troubleshooting. A beginner walkthrough (Japanese) with two sample videos: Zenn. - Dependency updates (#1648).
@mulmocast/typesis unchanged (2.21.0): neithersrc/types/nor its runtime dependencies changed.📦 npm:
[email protected]
What's Changed
- Update package20261015 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1648
- docs: add a user guide for talking avatars (AvatarScript) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1649
- fix: ask users for the avatarscript this repository is tested with (^0.5.0) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1651
Full Changelog: https://github.com/receptron/mulmocast-cli/compare/2.22.1...2.23.0
- Avatars need avatarscript 0.5 (#1651, #1650): the
- 2.22.12026-10-14 · 2026-10-14 22:28 UTC
查看更新说明
Highlights
- Image-only renders no longer need ffmpeg (#1646, #1645):
audioCheckerprobed the generated still PNG with ffprobe for every beat without a movie, somulmo images/generateBeatImagefailed withCannot find ffprobeafter writing the image. It now probes the movie file when there is one, and a file in the image slot only when it is not a still image.hasMovieAudiois unchanged; movies,moviePrompt, lip sync and animated beats still need ffmpeg.
📦 npm:
[email protected]
What's Changed
- fix: skip the audio probe for still images so image-only renders do not need ffmpeg by @isamu in https://github.com/receptron/mulmocast-cli/pull/1646
- release: 2.22.1 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1647
Full Changelog: https://github.com/receptron/mulmocast-cli/compare/2.22.0...2.22.1
- Image-only renders no longer need ffmpeg (#1646, #1645):
查看更新说明
Highlights
- Browser: background images and slide branding in
beatToHtml(#1642, #1640): newBeatHtmlOptions—backgroundImage(deck-level default; a beat's ownimage.backgroundImage/nullstill wins),branding(deck-level slide branding) andresolveMediaUrl(maps a media source to a URL the host can load).textSlide,markdown,chartandmermaidbeats draw the background, andslidebeats draw branding, as the PNG path does. Page-level rules come back in the newBeatHtmlFragment.documentCss - Browser: scripted and animated
html_tailwindbeats (#1643, #1641): the fragment now carriesdocumentScript— the animation runtime,window.__MULMOframe state, the author script and the final-frame draw — so a host that injectshtml,css,documentCssanddocumentScriptinto one document gets the same final frame as the PNG.htmlitself stays script-free; a script-only beat returnshtml: "" - The PNG / movie output is unchanged
📦 npm:
[email protected]What's Changed
- release: 2.21.0 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1636
- release: @mulmocast/types 2.21.0 by @isamu in https://github.com/receptron/mulmocast-cli/pull/1637
- chore: fail CI when types/ and the root disagree on a shared dependency by @isamu in https://github.com/receptron/mulmocast-cli/pull/1639
- feat(beat_html): draw backgrounds, slide branding and reference like the PNG render by @isamu in https://github.com/receptron/mulmocast-cli/pull/1642
- feat(beat_html): return html_tailwind scripts and animation as documentScript by @isamu in https://github.com/receptron/mulmocast-cli/pull/1643
- release: 2.22.0 (mulmocast) by @isamu in https://github.com/receptron/mulmocast-cli/pull/1644
Full Changelog: https://github.com/receptron/mulmocast-cli/compare/2.21.0...2.22.0
- Browser: background images and slide branding in
用户点评
登录用户的真实使用记录,可按版本和硬件筛选还没有人点评。第一个说出真实体验的人最有价值。
MulmoCast: A Multi-Modal Presentation Tool for the AI-Native Era
Quick Start Guide
If you want to try our beta version, follow the instruction in the release note below.
What is MulmoCast?
Note: The video version of "What is MulmoCast?" is available on X, which is created by MulmoCast itself.
MulmoCast is a next-generation presentation platform, purpose-built for a world where AI and humans collaborate to create and share ideas.
Unlike traditional tools like PowerPoint or Keynote—both designed in the pre-AI era for human creators—MulmoCast is AI-native: reimagined from the ground up to work hand-in-hand with generative AI that understands and produces natural language, images, audio, and video.
As AI takes on an increasingly central role in content creation, it needs more than raw capability—it needs an environment designed for its strengths. MulmoCast provides that environment, empowering AI to generate rich, coherent presentations across multiple formats, while keeping humans in the creative loop.
At the core of MulmoCast is MulmoScript, a JSON-based intermediate language that functions like a screenplay or web markup. Generated by large language models, MulmoScript defines everything from narrative structure to visuals, making it easy to produce presentations that adapt seamlessly across formats.
flowchart TD
S_TextEditor["Creator"] <--> S_AIChat2("LLM")
S_AIChat2 --> MulmoScript["MulmoScript"]
MulmoScript --> MulmoCast["MulmoCast"]
MulmoCast --> O_Video("Video") & O_Podcast("Podcast") & O_Slideshow("Slideshow") & O_PDF("PDF") & O_Manga("Manga") & O_SwipeAnime("Swipe Anime")
MulmoScript@{ shape: div-proc}
MulmoCast@{ shape: trap-t}
S_TextEditor:::StoryInput
S_AIChat2:::ScriptInput
O_Video:::ScriptOutput
O_Podcast:::ScriptOutput
O_Slideshow:::ScriptOutput
O_PDF:::ScriptOutput
O_Manga:::ScriptOutput
O_SwipeAnime:::ScriptOutput
classDef StoryInput stroke-width:1px, stroke-dasharray:none, stroke:#46EDC8, fill:#DEFFF8, color:#378E7A
classDef ScriptInput stroke-width:1px, stroke-dasharray:none, stroke:#374D7C, fill:#E2EBFF, color:#374D7C
classDef ScriptOutput stroke-width:1px, stroke-dasharray:none, stroke:#FBB35A, fill:#FFEFDB, color:#8F632D
In today’s world, people consume information through many channels—on Zoom calls, in Slack threads, via videos on the go, or through podcasts during commutes. Presentations can no longer be confined to a single format or device. That’s why MulmoCast is built to be truly multi-modal, enabling output not only as slide decks but also as videos, podcasts, manga-style comics, and PDF documents.
Whether you're building a podcast from a research report or turning a business pitch into a narrated video, MulmoCast transforms source material into dynamic, multi-format content with the help of state-of-the-art AI like ChatGPT and Claude.
MulmoCast isn't just a tool. It’s a new foundation for communication—one where humans and AI co-create across every mode of expression.
MulmoScript
MulmoScript is a simple JSON/YAML format for describing multi-modal content.
You can define speakers, text, images, and layout — all in one script.
Here is the "Hello World" in MulmoScript.
{
"$mulmocast": {
"version": "1.1"
},
"beats": [
{ "text": "Hello World" }
]
}
See MulmoScript Format for details on the structure.
Installation
npm install -g mulmocast
You'll also need to install ffmpeg:
# For macOS with Homebrew
brew install ffmpeg
# For other platforms
# Visit https://ffmpeg.org/download.html
You can also use Dockerfile which helps you install the pre-requisits.
docker build -t mulmo-cli .
You can use the Docker image like this:
docker run -e OPENAI_API_KEY=<your_openai_api_key> -it mulmo-cli mulmo tool scripting -i -t children_book -o ./ -s story
Configuration
Create a .env file in your project directory with the following API keys:
Required
OPENAI_API_KEY=your_openai_api_key
(Optional) For Google's image and TTS.
GEMINI_API_KEY=your_google_gemini_api_key
(Optional) For AI providers
# For Anthropic Claude (htmlPrompt feature)
ANTHROPIC_API_TOKEN=your_anthropic_api_token
For htmlPrompt configuration, see docs/image.md.
(Optional) For Movie models
REPLICATE_API_TOKEN=your_replicate_api_key
(Optional) For TTS models
# For ElevenLabs TTS
ELEVENLABS_API_KEY=your_elevenlabs_api_key
(Optional) to access web in mulmo tool
BROWSERLESS_API_TOKEN=your_browserless_api_token # to access web in mulmo tool
(Optional) Local usage tracking
MULMOCAST_DUMP_USAGE=1 # print JSON usage dump to stdout after each CLI action
MULMOCAST_DUMP_USAGE=/tmp/usage.json # ...or write it to a file
Token / per-second / per-char usage per provider:model. See docs/api.md for the full reference.
Google Vertex AI
For enterprise/production environments, or to use Veo movie models that are only available on Vertex AI, use Vertex AI with Application Default Credentials (ADC):
# Install gcloud CLI and authenticate
gcloud auth application-default login
Configure in MulmoScript:
{
"imageParams": {
"provider": "google",
"model": "gemini-2.5-flash-image",
"vertexai_project": "your-project-id",
"vertexai_location": "us-central1"
}
}
| Parameter | Description | Default |
|---|---|---|
vertexai_project | Google Cloud Project ID | None (enables Vertex AI mode when set) |
vertexai_location | Region | us-central1 |
For detailed setup instructions, see Vertex AI Setup Guide.
Azure OpenAI
To use Azure OpenAI instead of OpenAI API:
# For image generation
IMAGE_OPENAI_API_KEY=<your-azure-openai-api-key>
IMAGE_OPENAI_BASE_URL=https://<resource-name>.openai.azure.com/
# For TTS (Text-to-Speech)
TTS_OPENAI_API_KEY=<your-azure-openai-api-key>
TTS_OPENAI_BASE_URL=https://<resource-name>.openai.azure.com/
# For LLM (translate, scripting)
LLM_OPENAI_API_KEY=<your-azure-openai-api-key>
LLM_OPENAI_BASE_URL=https://<resource-name>.openai.azure.com/
LLM_OPENAI_API_VERSION=2025-04-01-preview # optional
MulmoScript configuration (same as OpenAI):
{
"imageParams": {
"provider": "openai",
"model": "gpt-image-1.5"
},
"speechParams": {
"speakers": {
"Presenter": {
"provider": "openai",
"voiceId": "alloy",
"model": "tts"
}
}
}
}
Important: Azure deployment names must match model names exactly (e.g., deployment name gpt-image-1.5 for model gpt-image-1.5).
For detailed setup and region availability, see Azure OpenAI Usage Guide.
mulmo.config.json
Create a mulmo.config.json file to set project-wide defaults. The CLI searches for it in CWD first, then home directory (~/).
{
"speechParams": {
"provider": "elevenlabs"
},
"imageParams": {
"provider": "google"
},
"audioParams": {
"bgm": { "kind": "path", "path": "assets/bgm.mp3" },
"bgmVolume": 0.15
}
}
Top-level keys are applied as defaults (script values take precedence). Use the override key to force values over scripts — useful for enterprise branding or TTS provider enforcement:
{
"speechParams": {
"provider": "elevenlabs"
},
"override": {
"speechParams": {
"provider": "elevenlabs",
"model": "eleven_multilingual_v2",
"speakers": {
"Presenter": { "provider": "elevenlabs", "voiceId": "Rachel" }
}
}
}
}
Priority chain: config (defaults) < template/style < script < config.override < presentationStyle (-p)
Note:
kind: "path"entries inmulmo.config.jsonare resolved relative to the script file directory, not the config file location. This is consistent with all other path resolution in MulmoScript.
Verify the merged result with:
mulmo tool info merged --script <script.json>
Workflow
- Create a MulmoScript JSON file with
mulmo tool scripting - Generate audio with
mulmo audio - Generate images with
mulmo images - Create final video with
mulmo movie
Quick Start
Step 1: Generate a MulmoScript with interactive mode
-
Step 1-1: Run the script generation command
mulmo tool scripting -i -t children_book -o ./ -s storyThis will initiate the script creation process.
-
Step 1-2: Interactive conversation with AI
After running the command, you'll engage in an interactive conversation with the AI to create your story script. The AI will guide you through the process and help shape your content based on your inputs. Once completed, a JSON file (like
story-1746600802426.json) will be generated.
Step 2: Generate both audio and images, then combine into video
mulmo movie {generated_script_file}
Replace {generated_script_file} with the output file from STEP 1, such as story-1746600802426.json.
Optionally, you can specify __clipboard as the script file name to paste the script from the clipboard, which is generated by other interactive environment such as ChatGPT or Claude.
Quick Start for Ghibli-Style Animation
![]()
Click the image above to watch an example of what you can create
Step 1: Check/Update Environment Setup
Verify your .env file contains:
OPENAI_API_KEY=your_openai_api_key
Note: Ensure your OpenAI organization is verified to access the GPT Image models. Visit https://platform.openai.com/settings/organization/general and complete the "Verifications" section.
Step 2: Generate a Ghibli-style MulmoScript
mulmo tool scripting -i -t ghibli_comic -o ./ -s story
This will initiate an interactive conversation with the AI to create your Ghibli-inspired story. Once completed, a JSON file (e.g., story-1747834931950.json) will be generated.
Step 3: Translate the MulmoScript
mulmo translate {generated_script_file_from_step_2}
Step 4: Generate video with Japanese subtitles
mulmo movie {generated_script_file_from_step_2} -c ja
The -c ja flag adds Japanese subtitles to your video.
When the process completes, the CLI will display the path to your generated video file:
Video created successfully! 14.939 sec
writing: /Users/username/path/to/output/story-1747834931950__ja.mp4
Generate MulmoScript
# Generate script from web content (requires Browserless API KEY)
mulmo tool scripting -u https://example.com
# Generate script from local file
mulmo tool scripting --input-file story.txt
# Generate script with interactive mode
mulmo tool scripting -i
Note:
- When -i is specified, --input-file value will be ignored
- When --input-file is specified, -u value will be ignored
Complete MulmoScript from minimal beats
You can create a minimal JSON with just beats and complete it with mulmo tool complete:
{
"beats": [{ "text": "Hello, welcome to MulmoCast!" }, { "text": "This is a simple example." }]
}
Save this as my_beats.json, then complete it with a style:
# Complete with built-in style
mulmo tool complete my_beats.json -s ani
# Complete with custom style file
mulmo tool complete my_beats.json -s ./my_style.json
# Output to specific file
mulmo tool complete my_beats.json -s ani -o my_script.json
This generates a complete MulmoScript with all required fields (canvasSize, speechParams, imageParams, etc.) from the style.
Generate content from MulmoScript
Mulmo provides several commands to handle different aspects of content creation:
# Generate audio from script
mulmo audio script.json
# Generate images for script
mulmo images script.json
# Generate both audio and images, then combine into video
mulmo movie script.json
# Translate script to Japanese
mulmo translate script.json
Usage tracking (token / character / predict-second per provider:model)
Any of the commands above can dump a JSON breakdown of upstream AI consumption when MULMOCAST_DUMP_USAGE is set:
# print JSON to stdout (pipe-friendly: `... | jq .`)
MULMOCAST_DUMP_USAGE=1 mulmo audio script.json
# ...or write it to a file
MULMOCAST_DUMP_USAGE=/tmp/usage.json mulmo movie script.json
Payload shape:
{
"records": 3,
"byModel": [
{ "provider": "openai", "model": "gpt-4o-mini-tts", "records": 1, "inputChars": 20 },
{ "provider": "gemini", "model": "gemini-3.8-flash-tts", "records": 1, "inputTokens": 9, "outputTokens": 59, "totalTokens": 68 },
{ "provider": "elevenlabs", "model": "eleven_multilingual_v2", "records": 1, "inputChars": 18 }
],
"snapshot": [/* per-call UsageRecord[] */]
}
byModel groups by provider:model (different models have different rate cards, so summing across them isn't meaningful). The full per-call snapshot is also included so a billing layer can apply its own grouping. See docs/api.md § Usage tracking for the per-agent field-population matrix and the programmatic (library) API.
Usage estimation (before running anything)
Every generation command accepts --estimate: it prints what the command would consume — scoped to that command's pipeline — and exits without generating:
mulmo movie script.json --estimate # table per provider:model + total cost
mulmo audio script.json --estimate --json # raw UsageEstimate[] records (pipe-friendly)
mulmo audio --estimate covers TTS (plus translation when -l differs from the script language); mulmo images / mulmo pdf cover image, htmlImage, movie, sound-effect, lip-sync and reference-media generation; mulmo movie covers everything; mulmo translate only translation. Values marked ~ are heuristic estimates; unmarked values are exact for the given script.
The library API can estimate the same thing — per beat, per process — without calling any API:
import { estimateUsage } from "mulmocast";
const estimates = estimateUsage(script, { targetLangs: ["ja"] });
// [{ process: "tts", beatIndex: 0, provider: "openai", model: "gpt-4o-mini-tts",
// inputChars: { value: 50, precision: "exact" }, outputTokens: { value: 150, precision: "estimated" },
// costUSD: 0.0019, pricingAsOf: "2026-07-03" }, ...]
Each metric carries a precision flag: "exact" for values that are deterministic from the script (TTS character counts, tokenized OpenAI prompts, fixed image-output token tables) and "estimated" for heuristics (LLM output length, speech duration derived from text). costUSD appears when pricing data exists in modelPricing (src/types/provider2agent.ts), where every price records the date it was last verified. See docs/api.md § Pre-run estimation.
Strict network mode (scripts you did not write)
HTML-based beats (html_tailwind, markdown, textSlide, chart, mermaid, slide, captions, HTML prompts) and PDF output are rendered in a headless browser that normally has full network access. For a script from an untrusted source, add --strict-network (or set MULMO_STRICT_NETWORK=1; library callers set context.strictNetwork):
mulmo images untrusted.json --strict-network
The renderer may then load only files in the script's folder and mulmocast's output folders, data: / blob: URLs, and the CDNs mulmocast's own templates use (cdn.tailwindcss.com, fonts.googleapis.com, fonts.gstatic.com, and on cdn.jsdelivr.net only the mermaid and Chart.js files the templates load). Anything else — other local files, remote images in the script, fetch, WebSockets, WebRTC, popups, preconnect hints — is blocked, and each blocked request is logged (strict network: blocked …). Files next to the script in the same folder remain readable, so keep an untrusted script in a folder of its own (a script loaded by URL gets the output folders only). Requests to the allowed CDNs still reach those providers, so treat what a page sends there as visible to them. Strict mode guards what the browser loads; files the script names with kind: "path" (images, movies, logos, mermaid or remotion code) are read by mulmocast itself and are not restricted yet (#1622). Remotion beats are always guarded this way. The vision beat renders in its own browser inside mulmocast-vision, which the guard cannot reach, so in strict mode a vision beat stops with an error instead of rendering unguarded.
Cache and Re-run
When running the same mulmo command multiple times, previously generated files are treated as cache. For example, audio or image files will not be regenerated if they already exist.
To force regeneration, delete the old files — including temporary files — under the output directory before re-running the command or use -f (force) option.
If you modify the text or instruction fields in a MulmoScript, mulmo will automatically detect the changes and regenerate the corresponding audio content upon re-run.
Slide Presentations
MulmoCast includes a powerful Slide DSL (type: "slide") for creating structured presentation slides with JSON. Slides are rendered via Tailwind CSS + Puppeteer into images.
Features
- 12 Layouts: title, columns, comparison, grid, bigQuote, stats, timeline, split, matrix, table, funnel, waterfall
- 10 Content Block Types: text, bullets, code, callout, metric, divider, image, imageRef, chart, mermaid
- Chart.js Plugins: sankey (
chartjs-chart-sankey) and treemap (chartjs-chart-treemap) auto-loaded by chart type - 13-Color Theme System: Semantic color palette with dark/light support
- 6 Preset Themes: dark, pop, warm, creative, minimal, corporate
Usage
Set a theme once with slideParams.theme, then use "type": "slide" in each beat:
{
"$mulmocast": { "version": "1.1" },
"slideParams": {
"theme": {
"colors": {
"bg": "0F172A",
"bgCard": "1E293B",
"bgCardAlt": "334155",
"text": "F8FAFC",
"textMuted": "CBD5E1",
"textDim": "64748B",
"primary": "3B82F6",
"accent": "8B5CF6",
"success": "22C55E",
"warning": "F59E0B",
"danger": "EF4444",
"info": "14B8A6",
"highlight": "EC4899"
},
"fonts": { "title": "Georgia", "body": "Calibri", "mono": "Consolas" }
}
},
"beats": [
{
"text": "Welcome to the presentation",
"image": {
"type": "slide",
"slide": { "layout": "title", "title": "Main Title", "subtitle": "Subtitle" }
}
}
]
}
Or use a preset presentation style:
mulmo tool complete beats.json -s slide_dark -o presentation.json
Available preset styles: slide_dark, slide_pop, slide_warm, slide_creative, slide_minimal, slide_corporate
For detailed layout specifications and content block reference, see the Slide DSL documentation.
Markdown Slide Styles
MulmoCast includes 100 pre-designed CSS styles for markdown slides, organized in 10 categories:
| Category | Description | Example Styles |
|---|---|---|
| business | Professional corporate designs | corporate-blue, executive-gray, finance-green |
| tech | Technology and developer themes | cyber-neon, matrix-green, terminal-dark |
| creative | Artistic and expressive styles | artistic-splash, watercolor-soft, graffiti |
| minimalist | Clean and simple designs | clean-white, zen-beige, nordic-light |
| nature | Nature-inspired themes | forest-green, ocean-blue, sunset-orange |
| dark | Dark mode and elegant themes | charcoal-elegant, midnight-blue, obsidian |
| colorful | Vibrant and bold colors | vibrant-pink, candy-colors, aurora |
| vintage | Retro and classic styles | retro-70s, art-deco, typewriter |
| japanese | Japanese aesthetic designs | washi-paper, sakura-pink, zen-garden |
| geometric | Pattern-based designs | hexagon-pattern, isometric, bauhaus |
Usage
Add the style property to a markdown beat:
{
"beats": [
{
"text": "Corporate presentation slide",
"image": {
"type": "markdown",
"markdown": "# Quarterly Report\n\n## Key Highlights\n\n- Revenue up 15%\n- New market expansion\n- Team growth",
"style": "corporate-blue"
}
}
]
}
Discover Available Styles
Use the mulmo tool info command to see all available styles:
mulmo tool info styles
MulmoScript Format
MulmoScript is a JSON format to define podcast or video scripts: Schema definition: schema.ts
Sample MulmoScript
https://github.com/receptron/mulmocast-cli/tree/main/scripts
Directory Structure
| Directory | Description |
|---|---|
output/ | Artifacts generated by commands — e.g., .json, audio, and video files |
output/audio/ | Temporary audio fragments used in the final audio assembly |
output/images/ | Image files generated by the images command |
output/cache/ | Internal cache files for various processing steps |
These directories are automatically created as needed by the
mulmocommands.
Help
CLI Usage
mulmo <command> [options]
Commands:
mulmo translate <file> Translate Mulmo script
mulmo audio <file> Generate audio files
mulmo images <file> Generate image files
mulmo movie <file> Generate movie file
mulmo pdf <file> Generate PDF files
mulmo markdown <file> Generate markdown files
mulmo bundle <file> Generate bundle files
mulmo html <file> Generate html files
mulmo tool <command> Generate Mulmo script and other tools
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
mulmo translate <file>
Translate Mulmo script
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
mulmo audio <file>
Generate audio files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
-a, --audiodir Audio output directory [string]
mulmo images <file>
Generate image files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
-i, --imagedir Image output directory [string]
mulmo movie <file>
Generate movie file
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
-a, --audiodir Audio output directory [string]
-i, --imagedir Image output directory [string]
-c, --caption Video captions
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
mulmo pdf <file>
Generate PDF files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
-i, --imagedir Image output directory [string]
--pdf_mode PDF mode
[string] [choices: "slide", "talk", "handout"] [default: "slide"]
--pdf_size PDF paper size (default: letter)
[choices: "letter", "a4"] [default: "letter"]
mulmo markdown <file>
Generate markdown files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
--image_width Image width (e.g., 400px, 50%, auto) [string]
mulmo html <file>
Generate html files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
--image_width Image width (e.g., 400px, 50%, auto) [string]
mulmo bundle <file>
Generate bundle files
Positionals:
file Mulmo Script File [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-l, --lang target language
[string] [choices: "en", "ja", "fr", "es", "de", "zh-CN", "zh-TW", "ko", "it",
"pt", "ar", "hi"]
-f, --force Force regenerate [boolean] [default: false]
-g, --grouped Output all files under output/<basename>/ directory
[boolean] [default: false]
--backup create backup media file [boolean] [default: false]
--strict-network Let HTML renderers reach only local files and the
CDNs mulmocast's templates use (also
MULMO_STRICT_NETWORK=1) [boolean] [default: false]
-p, --presentationStyle Presentation Style [string]
mulmo tool <command>
Generate Mulmo script and other tools
Commands:
mulmo tool scripting Generate mulmocast script
mulmo tool prompt Dump prompt from template
mulmo tool schema Dump mulmocast schema
mulmo tool story_to_script <file> Generate Mulmo script from story
mulmo tool whisper <file> Process file with whisper
mulmo tool complete <file> Complete MulmoScript with schema defaults
and optional style
mulmo tool info [category] Show available options (styles, bgm,
templates, voices, images, movies, llm,
themes, config, merged)
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
mulmo tool scripting
Generate mulmocast script
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-u, --url URLs to reference (required when not in interactive mode)
[array] [default: []]
--input-file input file name [string]
-i, --interactive Generate script in interactive mode with user prompts
[boolean]
-t, --template Template name to use
[string] [choices: "akira_comic", "ani", "business", "characters",
"children_book", "coding", "comic_strips", "documentary", "drslump_comic",
"ghibli_comic", "ghibli_comic_strips", "ghost_comic", "html", "image_prompt",
"leda", "onepiece_comic", "portrait_movie", "realistic_movie",
"sensei_and_taro", "shorts", "sifi_story", "trailer", "vision"]
-c, --cache cache dir [string]
-s, --script script filename [string] [default: "script"]
--llm llm
[string] [choices: "openai", "anthropic", "gemini", "groq", "mock"]
--llm_model llm model [string]
mulmo tool story_to_script <file>
Generate Mulmo script from story
Positionals:
file story file path [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --outdir output dir [string]
-b, --basedir base dir [string]
-t, --template Template name to use
[string] [choices: "akira_comic", "ani", "business", "characters",
"children_book", "coding", "comic_strips", "documentary", "drslump_comic",
"ghibli_comic", "ghibli_comic_strips", "ghost_comic", "html", "image_prompt",
"leda", "onepiece_comic", "portrait_movie", "realistic_movie",
"sensei_and_taro", "shorts", "sifi_story", "trailer", "vision"]
-s, --script script filename [string] [default: "script"]
--beats_per_scene beats per scene [number] [default: 3]
--llm llm
[string] [choices: "openai", "anthropic", "gemini", "groq", "mock"]
--llm_model llm model [string]
--mode story to script generation mode
[string] [choices: "step_wise", "one_step"] [default: "step_wise"]
mulmo tool prompt
Dump prompt from template
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-t, --template Template name to use
[string] [choices: "akira_comic", "ani", "business", "characters",
"children_book", "coding", "comic_strips", "documentary", "drslump_comic",
"ghibli_comic", "ghibli_comic_strips", "ghost_comic", "html", "image_prompt",
"leda", "onepiece_comic", "portrait_movie", "realistic_movie",
"sensei_and_taro", "shorts", "sifi_story", "trailer", "vision"]
mulmo tool schema
Dump mulmocast schema
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
mulmo tool complete <file>
Complete MulmoScript with schema defaults and optional style
Positionals:
file Input beats file path (JSON) [string] [required]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-o, --output Output file path (default: <file>_completed.json) [string]
-t, --template Template name to apply
[string] [choices: "akira_comic", "ani", "business", "characters",
"children_book", "coding", "comic_strips", "documentary", "drslump_comic",
"ghibli_comic", "ghibli_comic_strips", "ghost_comic", "html", "image_prompt",
"leda", "onepiece_comic", "portrait_movie", "realistic_movie",
"sensei_and_taro", "shorts", "sifi_story", "trailer", "vision"]
-s, --style Style name or file path (.json) [string]
Examples:
# Complete minimal script with schema defaults
mulmo tool complete input.json
# Apply built-in style
mulmo tool complete input.json -s ani
# Apply custom style file
mulmo tool complete input.json -s ./my_style.json
# Apply template
mulmo tool complete input.json -t children_book
mulmo tool info [category]
Show available options (styles, bgm, templates, voices, images, movies, llm,
themes, config, merged)
Positionals:
category Category to show info for
[string] [choices: "styles", "bgm", "templates", "voices", "images", "movies",
"llm", "themes", "config", "merged"]
Options:
--version Show version number [boolean]
-v, --verbose verbose log [boolean] [required] [default: false]
-h, --help Show help [boolean]
-F, --format Output format
[string] [choices: "text", "json", "yaml"] [default: "text"]
-S, --script Script file path (required for 'merged' category) [string]
Examples:
# Show all available categories
mulmo tool info
# List all 100 markdown styles
mulmo tool info styles
# List available BGM assets
mulmo tool info bgm
# List TTS providers and voices
mulmo tool info voices
# Output as JSON for programmatic use
mulmo tool info styles --format json
Contributing
For developers interested in contributing to this project, please see CONTRIBUTING.md.