Free Music

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

Security Scan

The skill's behavior mostly matches its stated purpose (adding music to videos) but contains a few inconsistencies and minor scope-creep (metadata vs. registry mismatch, instructions that require reading installer paths and implicit filesystem access) that warrant caution before installing.

Purpose & Capability

The name/description (add background music to videos) aligns with the actions the SKILL.md instructs (upload video, call a cloud render API, return download URL). Requesting a single service token (NEMO_TOKEN) is appropriate for a cloud rendering service.

Instruction Scope

Most instructions stay within the stated purpose (session creation, SSE messaging, upload, export, polling). Minor scope items: the skill asks the agent to detect installation path to populate X-Skill-Platform (requires inspecting agent filesystem/runtime path) and to store session_id between requests; it also explicitly instructs not to show raw API responses or tokens to users, which is plausible for UX but reduces transparency. These are not clearly malicious but broaden the agent's actions beyond simple API calls.

Install Mechanism

No install spec and no code files — instruction-only skill — so nothing is written to disk by an installer. This is the lowest-risk install pattern.

Credentials

The skill declares a single primary env var (NEMO_TOKEN), which is reasonable. However, the YAML frontmatter in SKILL.md includes a configPaths entry (~/.config/nemovideo/) while the registry metadata lists no required config paths — this inconsistency may indicate a hidden expectation to read that config directory (potentially to find tokens or configs). The skill also advises auto-generating and storing anonymous tokens, which means credentials will be created and persisted by the agent if NEMO_TOKEN is absent.

Persistence & Privilege

The skill is not always-enabled and does not request elevated platform privileges. Storing a session_id and re-using the NEMO_TOKEN for the session is normal for a service client. It does not request modifying other skills or global agent settings in the instructions.

What to consider before installing

This skill appears to do what it says — it uploads user video files to an external service (mega-api-prod.nemovideo.ai) to add royalty-free music and returns a downloadable file. Before installing, consider: 1) Privacy and data residency — your videos are uploaded to a third-party cloud; check the service's privacy/retention policy and whether you’re comfortable with that. 2) Token handling — the skill will create and persist an anonymous NEMO_TOKEN if none is provided; you can avoid automatic token creation by pre-providing your own token or declining the skill. 3) Metadata mismatch — the SKILL.md mentions a config path (~/.config/nemovideo/) but the registry metadata lists no required config paths; ask the author which is correct and what (if any) local files will be read. 4) Attribution headers and install-path detection require the agent to inspect its runtime/install path; confirm you’re comfortable with the agent reading that path. If you need higher assurance, ask the publisher for a homepage, privacy policy, and proof of ownership of the mega-api-prod.nemovideo.ai domain before using the skill.

Getting Started

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

Try saying:

• "add my video clips"
• "export 1080p MP4"
• "add upbeat background music to my"

First-Time Connection

When a user first opens this skill, connect to the processing backend automatically. Briefly let them know (e.g. "Setting up...").

Authentication: Check if NEMO_TOKEN is set in the environment. If it is, skip to step 2.

1. Obtain a free token: Generate a random UUID as client identifier. POST to https://mega-api-prod.nemovideo.ai/api/auth/anonymous-token with header X-Client-Id set to that UUID. The response data.token is your NEMO_TOKEN — 100 free credits, valid 7 days.
2. Create a session: POST to https://mega-api-prod.nemovideo.ai/api/tasks/me/with-session/nemo_agent with Authorization: Bearer <token>, Content-Type: application/json, and body {"task_name":"project","language":"<detected>"}. Store the returned session_id for all subsequent requests.

Keep setup communication brief. Don't display raw API responses or token values to the user.

Free Music — Add Music to Videos Free

This tool takes your video clips 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 montage in MP4 format and want to add upbeat background music to my video for free — the backend processes it in about 20-40 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, 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.

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

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

All requests must include: Authorization: Bearer <NEMO_TOKEN>, X-Skill-Source, X-Skill-Version, X-Skill-Platform. Missing attribution headers will cause export to fail with 402.

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

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

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

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

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

Session state: GET /api/state/nemo_agent/me/<sid>/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_<ts>","sessionId":"<sid>","draft":<json>,"output":{"format":"mp4","quality":"high"}}. Poll GET /api/render/proxy/lambda/<id> 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.

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.

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

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)

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=<id> (get <id> 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

Tips and Tricks

The backend processes faster when you're specific. Instead of "make it look better", try "add upbeat background music to my video for free" — 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 social platforms.

Common Workflows

Quick edit: Upload → "add upbeat background music to my video for free" → Download MP4. Takes 20-40 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.