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dsewell-583h0

Caption Generator For Video

by dsewell-583h0 · GitHub ↗ · v1.0.0 · MIT-0
cross-platform ⚠ suspicious
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Install in OpenClaw
/install caption-generator-for-video
Description
add video files into captioned video files with this skill. Works with MP4, MOV, AVI, WebM files up to 500MB. content creators and marketers use it for addin...
README (SKILL.md)

Getting Started

Got video files to work with? Send it over and tell me what you need — I'll take care of the AI subtitle generation.

Try saying:

  • "add a 3-minute tutorial video recorded on a smartphone into a 1080p MP4"
  • "add captions in English and Spanish with white text at the bottom"
  • "adding subtitles to YouTube and social media videos for content creators and marketers"

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.

Caption Generator for Video — Auto-Generate Captions for Videos

Drop your video files in the chat and tell me what you need. I'll handle the AI subtitle generation on cloud GPUs — you don't need anything installed locally.

Here's a typical use: you send a a 3-minute tutorial video recorded on a smartphone, ask for add captions in English and Spanish with white text at the bottom, and about 30-60 seconds later you've got a MP4 file ready to download. The whole thing runs at 1080p by default.

One thing worth knowing — shorter clips under 5 minutes generate captions significantly faster.

Matching Input to Actions

User prompts referencing caption generator for video, 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.

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

Three attribution headers are required on every request and must match this file's frontmatter:

Header Value
X-Skill-Source caption-generator-for-video
X-Skill-Version frontmatter version
X-Skill-Platform auto-detect: clawhub / cursor / unknown from install path

API base: https://mega-api-prod.nemovideo.ai

Create session: POST /api/tasks/me/with-session/nemo_agent — body {"task_name":"project","language":"\x3Clang>"} — returns task_id, session_id.

Send message (SSE): POST /run_sse — body {"app_name":"nemo_agent","user_id":"me","session_id":"\x3Csid>","new_message":{"parts":[{"text":"\x3Cmsg>"}]}} with Accept: text/event-stream. Max timeout: 15 minutes.

Upload: POST /api/upload-video/nemo_agent/me/\x3Csid> — file: multipart -F "files=@/path", or URL: {"urls":["\x3Curl>"],"source_type":"url"}

Credits: GET /api/credits/balance/simple — returns available, frozen, total

Session state: GET /api/state/nemo_agent/me/\x3Csid>/latest — key fields: data.state.draft, data.state.video_infos, data.state.generated_media

Export (free, no credits): POST /api/render/proxy/lambda — body {"id":"render_\x3Cts>","sessionId":"\x3Csid>","draft":\x3Cjson>,"output":{"format":"mp4","quality":"high"}}. Poll GET /api/render/proxy/lambda/\x3Cid> every 30s until status = completed. Download URL at output.url.

Supported formats: mp4, mov, avi, webm, mkv, jpg, png, gif, webp, mp3, wav, m4a, aac.

Error Codes

  • 0 — success, continue normally
  • 1001 — token expired or invalid; re-acquire via /api/auth/anonymous-token
  • 1002 — session not found; create a new one
  • 2001 — out of credits; anonymous users get a registration link with ?bind=\x3Cid>, registered users top up
  • 4001 — unsupported file type; show accepted formats
  • 4002 — file too large; suggest compressing or trimming
  • 400 — missing X-Client-Id; generate one and retry
  • 402 — free plan export blocked; not a credit issue, subscription tier
  • 429 — rate limited; wait 30s and retry once

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

SSE Event Handling

Event Action
Text response Apply GUI translation (§4), present to user
Tool call/result Process internally, don't forward
heartbeat / empty data: Keep waiting. Every 2 min: "⏳ Still working..."
Stream closes Process final response

~30% of editing operations return no text in the SSE stream. When this happens: poll session state to verify the edit was applied, then summarize changes to the user.

Draft JSON uses short keys: t for tracks, tt for track type (0=video, 1=audio, 7=text), sg for segments, d for duration in ms, m for metadata.

Example timeline summary:

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

Tips and Tricks

The backend processes faster when you're specific. Instead of "make it look better", try "add captions in English and Spanish with white text at the bottom" — 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.

Common Workflows

Quick edit: Upload → "add captions in English and Spanish with white text at the bottom" → 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.

Usage Guidance
This skill appears to be a straightforward cloud captioning integration: it will upload files you provide to mega-api-prod.nemovideo.ai and requires a NEMO_TOKEN (it can also request an anonymous token for you). Before installing, consider: (1) Privacy — your videos and audio will be sent to a third-party service; avoid uploading sensitive or confidential content. (2) Config-path mismatch — the SKILL.md suggests access to ~/.config/nemovideo/ but the registry did not list any config paths; ask the author whether the agent will read that directory and what it contains. (3) Token handling — confirm how long tokens (anonymous or provided) are stored and where; anonymous tokens grant credits and could be reused. (4) Verify the API host (mega-api-prod.nemovideo.ai) and check the service's privacy/retention policy. If these points are acceptable or clarified, the skill's behavior aligns with its purpose; otherwise proceed only after clarification.
Capability Analysis
Type: OpenClaw Skill Name: caption-generator-for-video Version: 1.0.0 The skill 'caption-generator-for-video' is a legitimate integration for a video processing service hosted at nemovideo.ai. It facilitates video uploads, caption generation, and file downloads through a structured API. While it requires network access and a specific configuration path (~/.config/nemovideo/), these permissions are strictly aligned with its stated purpose. The instructions in SKILL.md guide the agent through session management and error handling without any signs of malicious intent, data exfiltration, or harmful prompt injection.
Capability Assessment
Purpose & Capability
Name/description match the runtime instructions: the SKILL.md describes uploading videos and creating render/export jobs on a remote nemovideo.ai API and expects a service token (NEMO_TOKEN). Requiring a token for a cloud video-captioning backend is proportional to the stated purpose.
Instruction Scope
Instructions explicitly direct the agent to upload user files (multipart or URL) and to POST/GET to numerous endpoints on mega-api-prod.nemovideo.ai, create sessions, poll renders, and handle SSE. That is expected for cloud rendering, but users should be aware: their video/audio files and any data sent in requests will be transmitted to that third-party service. The skill also instructs auto-acquiring an anonymous token if none is present (POSTing to the auth endpoint) and to auto-detect an install path to set X-Skill-Platform — these require the agent to generate identifiers and possibly inspect environment/paths.
Install Mechanism
No install spec and no code files — instruction-only skill. Lowest install risk since nothing is downloaded or written by an installer.
Credentials
PrimaryEnv is NEMO_TOKEN which fits the API usage. However SKILL.md frontmatter metadata includes a configPaths entry (~/.config/nemovideo/) while the registry metadata earlier listed none; this mismatch is unexplained. If the skill expects to read a user config directory, that grants access to potentially sensitive local files (tokens, settings). Confirm whether the agent will read that path and why. Otherwise the single required env var is proportionate.
Persistence & Privilege
always is false and the skill does not request persistent installation or modifications to other skills. It does instruct storing/using a session token returned by the backend for the duration of a job, which is normal for a remote service.
How to Use
  1. Make sure OpenClaw is installed (local or Docker)
  2. Run the install command in chat: /install caption-generator-for-video
  3. After installation, invoke the skill by name or use /caption-generator-for-video
  4. Provide required inputs per the skill's parameter spec and get structured output
Version History
v1.0.0
Initial release of Caption Generator for Video — Auto-Generate Captions for Videos. - Upload video files (MP4, MOV, AVI, WebM up to 500MB) and auto-generate captions using cloud-based AI. - Supports instructions such as adding subtitles in multiple languages, choosing text styles, and exporting in 1080p MP4 format. - Fast processing (30–60 seconds per video) with automatic cloud session creation and status updates. - Provides full workflow: upload, edit, preview, export, and download captioned videos. - Built-in handling for credits, upload limits, and error codes for a smooth user experience.
Metadata
Slug caption-generator-for-video
Version 1.0.0
License MIT-0
All-time Installs 0
Active Installs 0
Total Versions 1
Frequently Asked Questions

What is Caption Generator For Video?

add video files into captioned video files with this skill. Works with MP4, MOV, AVI, WebM files up to 500MB. content creators and marketers use it for addin... It is an AI Agent Skill for Claude Code / OpenClaw, with 82 downloads so far.

How do I install Caption Generator For Video?

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

Is Caption Generator For Video free?

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

Which platforms does Caption Generator For Video support?

Caption Generator For Video is cross-platform and runs anywhere OpenClaw / Claude Code is available (cross-platform).

Who created Caption Generator For Video?

It is built and maintained by dsewell-583h0 (@dsewell-583h0); the current version is v1.0.0.

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