Description

content creators and marketers add video files into captioned video files using this skill. Accepts MP4, MOV, AVI, WebM up to 500MB, renders on cloud GPUs at...

README (SKILL.md)

Getting Started

Share your video files and I'll get started on AI subtitle generation. Or just tell me what you're thinking.

Try saying:

"add my video files"
"export 1080p MP4"
"add captions in English and Spanish"

Getting Connected

Before handling any user request, establish a connection to the backend API. Show a brief status like "Connecting...".

If NEMO_TOKEN is in the environment, use it directly and create a session. Otherwise, acquire a free starter token:

Generate a UUID as client identifier
POST to https://mega-api-prod.nemovideo.ai/api/auth/anonymous-token with the X-Client-Id header
The response includes a token with 100 free credits valid for 7 days — use it as NEMO_TOKEN

Then create a session by POSTing to https://mega-api-prod.nemovideo.ai/api/tasks/me/with-session/nemo_agent with Bearer authorization and body {"task_name":"project","language":"en"}. The session_id in the response is needed for all following requests.

Tell the user you're ready. Keep the technical details out of the chat.

Auto Caption Online — Generate Captions for Videos Automatically

Name: Auto Caption Online
Author: mhogan2013-9

Send me your video files and describe the result you want. The AI subtitle generation runs on remote GPU nodes — nothing to install on your machine.

A quick example: upload a 3-minute tutorial video in MP4 format, type "add captions in English and Spanish automatically", and you'll get a 1080p MP4 back in roughly 30-60 seconds. All rendering happens server-side.

Worth noting: shorter clips under 5 minutes generate captions significantly faster.

Matching Input to Actions

User prompts referencing auto caption online, aspect ratio, text overlays, or audio tracks get routed to the corresponding action via keyword and intent classification.

User says...	Action	Skip SSE?
"export" / "导出" / "download" / "send me the video"	→ §3.5 Export	✅
"credits" / "积分" / "balance" / "余额"	→ §3.3 Credits	✅
"status" / "状态" / "show tracks"	→ §3.4 State	✅
"upload" / "上传" / user sends file	→ §3.2 Upload	✅
Everything else (generate, edit, add BGM…)	→ §3.1 SSE	❌

Cloud Render Pipeline Details

Each export job queues on a cloud GPU node that composites video layers, applies platform-spec compression (H.264, up to 1080x1920), and returns a download URL within 30-90 seconds. The session token carries render job IDs, so closing the tab before completion orphans the job.

Base URL: https://mega-api-prod.nemovideo.ai

Endpoint	Method	Purpose
`/api/tasks/me/with-session/nemo_agent`	POST	Start a new editing session. Body: `{"task_name":"project","language":"\x3Clang>"}`. Returns `session_id`.
`/run_sse`	POST	Send a user message. Body includes `app_name`, `session_id`, `new_message`. Stream response with `Accept: text/event-stream`. Timeout: 15 min.
`/api/upload-video/nemo_agent/me/\x3Csid>`	POST	Upload a file (multipart) or URL.
`/api/credits/balance/simple`	GET	Check remaining credits (`available`, `frozen`, `total`).
`/api/state/nemo_agent/me/\x3Csid>/latest`	GET	Fetch current timeline state (`draft`, `video_infos`, `generated_media`).
`/api/render/proxy/lambda`	POST	Start export. Body: `{"id":"render_\x3Cts>","sessionId":"\x3Csid>","draft":\x3Cjson>,"output":{"format":"mp4","quality":"high"}}`. Poll status every 30s.

Accepted file types: mp4, mov, avi, webm, mkv, jpg, png, gif, webp, mp3, wav, m4a, aac.

Skill attribution — read from this file's YAML frontmatter at runtime:

X-Skill-Source: auto-caption-online
X-Skill-Version: from frontmatter version
X-Skill-Platform: detect from install path (~/.clawhub/ → clawhub, ~/.cursor/skills/ → cursor, else unknown)

Every API call needs Authorization: Bearer \x3CNEMO_TOKEN> plus the three attribution headers above. If any header is missing, exports return 402.

Error Handling

Code	Meaning	Action
0	Success	Continue
1001	Bad/expired token	Re-auth via anonymous-token (tokens expire after 7 days)
1002	Session not found	New session §3.0
2001	No credits	Anonymous: show registration URL with `?bind=\x3Cid>` (get `\x3Cid>` from create-session or state response when needed). Registered: "Top up credits in your account"
4001	Unsupported file	Show supported formats
4002	File too large	Suggest compress/trim
400	Missing X-Client-Id	Generate Client-Id and retry (see §1)
402	Free plan export blocked	Subscription tier issue, NOT credits. "Register or upgrade your plan to unlock export."
429	Rate limit (1 token/client/7 days)	Retry in 30s once

Reading the SSE Stream

Text events go straight to the user (after GUI translation). Tool calls stay internal. Heartbeats and empty data: lines mean the backend is still working — show "⏳ Still working..." every 2 minutes.

About 30% of edit operations close the stream without any text. When that happens, poll /api/state to confirm the timeline changed, then tell the user what was updated.

Backend Response Translation

The backend assumes a GUI exists. Translate these into API actions:

Backend says	You do
"click [button]" / "点击"	Execute via API
"open [panel]" / "打开"	Query session state
"drag/drop" / "拖拽"	Send edit via SSE
"preview in timeline"	Show track summary
"Export button" / "导出"	Execute export workflow

Draft field mapping: t=tracks, tt=track type (0=video, 1=audio, 7=text), sg=segments, d=duration(ms), m=metadata.

Timeline (3 tracks): 1. Video: city timelapse (0-10s) 2. BGM: Lo-fi (0-10s, 35%) 3. Title: "Urban Dreams" (0-3s)

Common Workflows

Quick edit: Upload → "add captions in English and Spanish automatically" → Download MP4. Takes 30-60 seconds for a 30-second clip.

Batch style: Upload multiple files in one session. Process them one by one with different instructions. Each gets its own render.

Iterative: Start with a rough cut, preview the result, then refine. The session keeps your timeline state so you can keep tweaking.

Tips and Tricks

The backend processes faster when you're specific. Instead of "make it look better", try "add captions in English and Spanish automatically" — concrete instructions get better results.

Max file size is 500MB. Stick to MP4, MOV, AVI, WebM for the smoothest experience.

Export as MP4 for widest compatibility across platforms and devices.

Usage Guidance

This skill appears to do what it says: it uploads videos to a remote nemo-backend (mega-api-prod.nemovideo.ai) for cloud GPU captioning and needs a single token (NEMO_TOKEN). Before installing or using it: 1) Be aware your videos will be sent to an external service — avoid sending sensitive or private footage unless you trust the service. 2) The skill's source/homepage is missing and owner metadata is minimal; if you plan to use it in production, verify the service/operator and privacy/retention policies. 3) Confirm the small metadata mismatch (SKILL.md references '~/.config/nemovideo/' while registry metadata listed no config paths) with the publisher to ensure no unexpected file access. If you need higher assurance, request a published homepage, privacy policy, or official service documentation before using the skill with real content.

Capability Analysis

Type: OpenClaw Skill Name: auto-caption-online Version: 1.0.0 The 'auto-caption-online' skill is a legitimate integration for a video processing service hosted at mega-api-prod.nemovideo.ai. Its core functionality involves uploading video files to a remote GPU-accelerated backend for captioning and rendering, which is clearly aligned with its stated purpose. The skill includes detailed instructions for the agent to manage sessions, handle anonymous authentication for free credits, and process server-sent events (SSE). While it performs minor environment discovery (checking its install path for attribution headers), there is no evidence of malicious intent, exfiltration of sensitive local data (like SSH or AWS keys), or unauthorized command execution.

Capability Assessment

✓ Purpose & Capability

The skill is named and described as an online auto-captioning service and its runtime instructions exclusively describe uploading video files, creating a session, sending SSE messages, polling render status, and downloading results. Requesting a single service token (NEMO_TOKEN) is coherent with the stated cloud-rendering purpose.

ℹ Instruction Scope

Instructions limit actions to API calls to the nemo backend, file uploads, SSE reading, session management, and error handling. They also instruct detecting install path (to set X-Skill-Platform) and reading frontmatter values for attribution headers; this requires access to the agent's environment/paths to determine platform, which is reasonable for attribution but should be noted. No instructions ask for unrelated local files or unrelated environment variables.

✓ Install Mechanism

There is no install spec and no code files — the skill is instruction-only, so nothing is downloaded or written to disk by the skill itself. This is the lowest-risk install model.

ℹ Credentials

The skill only requires a single credential, NEMO_TOKEN, which is appropriate for a cloud API. It also instructs how to obtain an anonymous token if none is present. One minor inconsistency: the registry metadata lists no required config paths, while the SKILL.md frontmatter names '~/.config/nemovideo/' as a configPath — this mismatch should be clarified.

✓ Persistence & Privilege

The skill is not marked always:true and does not request persistent system-level privileges. Autonomous invocation is allowed (platform default) but not combined with broad credential requests, so exposure is limited to the single service token and operations described.

Version History

v1.0.0

Auto Caption Online 1.0.0 — initial release. - Instantly generates subtitles for uploaded videos (MP4, MOV, AVI, WebM up to 500MB) using cloud GPU rendering. - Supports video edits and exports at 1080p, returning captioned MP4 files in 30–60 seconds. - Handles multilingual captions (e.g., English, Spanish) and batch processing in a session-based workflow. - Simple onboarding with free credit token management; works out-of-the-box for new users. - Clear error handling and onboarding instructions for session, token, and file support issues.

Metadata

Slug auto-caption-online

Version 1.0.0

License MIT-0

All-time Installs 0

Active Installs 0

Total Versions 1

Frequently Asked Questions

What is Auto Caption Online?

content creators and marketers add video files into captioned video files using this skill. Accepts MP4, MOV, AVI, WebM up to 500MB, renders on cloud GPUs at... It is an AI Agent Skill for Claude Code / OpenClaw, with 99 downloads so far.

How do I install Auto Caption Online?

Run "/install auto-caption-online" in the OpenClaw or Claude Code chat to install it in one step — no extra setup required.

Is Auto Caption Online free?

Yes, Auto Caption Online is completely free, licensed under MIT-0. You can download, install and use it at no cost.

Which platforms does Auto Caption Online support?

Auto Caption Online is cross-platform and runs anywhere OpenClaw / Claude Code is available (cross-platform).

Who created Auto Caption Online?

It is built and maintained by mhogan2013-9 (@mhogan2013-9); the current version is v1.0.0.

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