Free Music Cog

Skip the learning curve of professional editing software. Describe what you want — add free background music to my video automatically — and get music-backed...

Security Scan

The skill's instructions are broadly consistent with a cloud-based video/music service, but lack of a verifiable source/homepage, a mismatch about declared config-paths, and the fact it uploads user videos to a third-party API are notable risks you should understand before installing or using it.

Purpose & Capability

Name/description (add royalty-free music to videos) match the runtime instructions (endpoints for upload, session, export). The single required env var (NEMO_TOKEN) is appropriate for an API-backed service. However, SKILL.md frontmatter declares a config path (~/.config/nemovideo/) that the registry metadata reported as 'none' — this mismatch is unexplained and worth verifying.

Instruction Scope

Instructions direct the agent to: create or reuse a bearer token, POST potentially large user video files (up to 500MB) to https://mega-api-prod.nemovideo.ai, create sessions, poll render status, and read the skill's YAML frontmatter at runtime to set attribution headers. Uploading user files and reading local config/frontmatter are expected for this use case, but they are privacy-sensitive actions and the skill's origin is unknown. The instructions also require storing session_id/token state and explicitly tell the agent not to print tokens (which is good), but they do not clearly specify where or how long tokens/session data are persisted.

Install Mechanism

This is an instruction-only skill with no install spec and no code files — lowest install risk. Nothing is written to disk by an installer step from the skill itself.

Credentials

Only NEMO_TOKEN is required, which is proportional for calling the service. However, the frontmatter indicates the skill may read a config path (~/.config/nemovideo/) to locate credentials/preferences; that access was not declared in the registry's 'Required config paths' field. Implicit file access to a user's home directory increases the privacy/credential risk and should be explicitly disclosed.

Persistence & Privilege

The skill is not marked 'always:true' and is user-invocable. It requests session tokens and may save session_id locally for the duration of a session, which is normal. It does not request system-wide privileges or claim to modify other skills.

What to consider before installing

This skill appears to be a cloud-backed video/music processor and will upload whatever video files you provide to https://mega-api-prod.nemovideo.ai and use a bearer token (NEMO_TOKEN). Before using it: 1) Verify the service/operator — there is no homepage or source URL in the registry; prefer skills with a verifiable publisher. 2) Don't upload sensitive or private video/audio until you trust the destination and its privacy policy. 3) Check whether you already have credentials in ~/.config/nemovideo/ (the skill may try to read that); remove or inspect them if you don't want them used. 4) If possible, test with a short non-sensitive sample file and a disposable token (anonymous token flow is supported). 5) Confirm how long session tokens are stored and where; revoke tokens or clear saved session data after use. If any of these points are unacceptable, avoid installing or using this skill.

Getting Started

Share your video files and I'll get started on royalty-free music addition. Or just tell me what you're thinking.

Try saying:

• "add my video files"
• "export 1080p MP4"
• "add free background music to my"

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.

Free Music Cog — Add Royalty-Free Music to Videos

This tool takes your video files and runs royalty-free music addition through a cloud rendering pipeline. You upload, describe what you want, and download the result.

Say you have a 2-minute travel vlog clip and want to add free background music to my video automatically — the backend processes it in about 30-60 seconds and hands you a 1080p MP4.

Tip: shorter clips process faster and let you preview multiple music tracks quickly.

Matching Input to Actions

User prompts referencing free music cog, 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: free-music-cog
• 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 <NEMO_TOKEN> plus the three attribution headers above. If any header is missing, exports return 402.

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)

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

Tips and Tricks

The backend processes faster when you're specific. Instead of "make it look better", try "add free background music to my video 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 YouTube, TikTok, and Instagram.

Common Workflows

Quick edit: Upload → "add free background music to my video 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.