Ai Subtitles For Video

Get captioned video files ready to post, without touching a single slider. Upload your video files (MP4, MOV, AVI, WebM, up to 500MB), say something like "ad...

Security Scan

The skill mostly matches its stated purpose (upload video, generate/burn captions remotely) but contains small incoherences about local config access and metadata that warrant caution before use.

Purpose & Capability

Name/description match the runtime instructions: the skill uploads user videos to a remote render service and returns processed MP4s, which justifies requiring an API token. However the YAML frontmatter lists a required config path (~/.config/nemovideo/) while the registry metadata earlier reported no config paths — that mismatch is unexplained and could indicate the skill expects to read or write local config even though instructions don't describe doing so.

Instruction Scope

SKILL.md instructs the agent to POST video files and commands to a remote API (mega-api-prod.nemovideo.ai) and to create/refresh anonymous tokens if NEMO_TOKEN is absent — this is appropriate for a cloud render service. It also asks the agent to detect install path to populate an X-Skill-Platform header (reading install path may require filesystem access); the instructions otherwise do not ask the agent to read unrelated system files or secrets. No instructions request unrelated credentials or to exfiltrate data beyond the rendering service, but the platform-detection step is a minor scope creep.

Install Mechanism

There is no install spec and no code files; the skill is instruction-only, which is the lowest-risk install mechanism.

Credentials

The only declared required credential is NEMO_TOKEN (primaryEnv), which is proportionate for calling the service. The skill also documents an anonymous-token flow so users don't strictly need to provision a secret. The unexplained config path in frontmatter (~/.config/nemovideo/) is inconsistent with other metadata and the instructions — if the skill will read/write that path it should be justified. Confirm whether NEMO_TOKEN is the only secret needed and whether local config will actually be accessed.

Persistence & Privilege

always is false and the skill does not request persistent/autostart privileges. It does ask to save session_id for job tracking (normal). There is no indication it will modify other skills or system-wide settings.

What to consider before installing

This skill appears to do what it says: upload videos to a remote service and return captioned/burned-in output. Before installing or using it, consider: (1) You will be uploading your video content to https://mega-api-prod.nemovideo.ai — confirm you trust that service and its privacy/retention policy before sending sensitive video. (2) The skill asks for NEMO_TOKEN but also documents an anonymous-token flow — prefer the anonymous flow unless you understand the token's scope. (3) The skill's frontmatter mentions a local config path (~/.config/nemovideo/) even though runtime instructions don't describe reading it; ask the author to clarify whether the skill will access local files. (4) Attribution headers (X-Skill-Source/Version/Platform) will be sent on each request and may reveal your environment; ensure you’re comfortable with that metadata being transmitted. If any of these are unacceptable, don't install; otherwise use the anonymous-token flow and avoid providing high-privilege or organization-wide secrets.

Getting Started

Ready when you are. Drop your video files here or describe what you want to make.

Try saying:

• "add a 3-minute YouTube tutorial recording into a 1080p MP4"
• "add captions in English and Spanish"
• "adding subtitles to YouTube videos for YouTubers and content creators"

Automatic Setup

On first interaction, connect to the processing API before doing anything else. Show a brief status like "Setting things up...".

Token: If NEMO_TOKEN environment variable is already set, use it and skip to Session below.

Free token: Generate a UUID as client identifier, then POST to https://mega-api-prod.nemovideo.ai/api/auth/anonymous-token with header X-Client-Id: <uuid>. The response field data.token becomes your NEMO_TOKEN (100 credits, 7-day expiry).

Session: POST to https://mega-api-prod.nemovideo.ai/api/tasks/me/with-session/nemo_agent with Bearer auth and body {"task_name":"project"}. Save session_id from the response.

Confirm to the user you're connected and ready. Don't print tokens or raw JSON.

AI Subtitles for Video — Generate and Burn In Captions

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 YouTube tutorial recording, type "add captions in English and Spanish", 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 subtitles noticeably faster.

Matching Input to Actions

User prompts referencing ai subtitles 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.

All calls go to https://mega-api-prod.nemovideo.ai. The main endpoints:

1. Session — POST /api/tasks/me/with-session/nemo_agent with {"task_name":"project","language":"<lang>"}. Gives you a session_id.
2. Chat (SSE) — POST /run_sse with session_id and your message in new_message.parts[0].text. Set Accept: text/event-stream. Up to 15 min.
3. Upload — POST /api/upload-video/nemo_agent/me/<sid> — multipart file or JSON with URLs.
4. Credits — GET /api/credits/balance/simple — returns available, frozen, total.
5. State — GET /api/state/nemo_agent/me/<sid>/latest — current draft and media info.
6. Export — POST /api/render/proxy/lambda with render ID and draft JSON. Poll GET /api/render/proxy/lambda/<id> every 30s for completed status and download URL.

Formats: 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: ai-subtitles-for-video
• X-Skill-Version: from frontmatter version
• X-Skill-Platform: detect from install path (~/.clawhub/ → clawhub, ~/.cursor/skills/ → cursor, else unknown)

Include Authorization: Bearer <NEMO_TOKEN> and all attribution headers on every request — omitting them triggers a 402 on export.

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)

Translating GUI Instructions

The backend responds as if there's a visual interface. Map its instructions to API calls:

• "click" or "点击" → execute the action via the relevant endpoint
• "open" or "打开" → query session state to get the data
• "drag/drop" or "拖拽" → send the edit command through SSE
• "preview in timeline" → show a text summary of current tracks
• "Export" or "导出" → run the 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.

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=<id>, 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

Common Workflows

Quick edit: Upload → "add captions in English and Spanish" → 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" — 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.