Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add happycapy-ai/Happycapy-skills --skill video-downloadergit clone --depth 1 https://github.com/happycapy-ai/Happycapy-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/happycapy-ai/happycapy-skills/video-downloader)<a href="https://agentmods.dev/skills/happycapy-ai/happycapy-skills/video-downloader"><img src="https://agentmods.dev/badge/skills/happycapy-ai/happycapy-skills/video-downloader/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/happycapy-ai/happycapy-skills/video-downloader"><img src="https://agentmods.dev/badge/skills/happycapy-ai/happycapy-skills/video-downloader.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00028 | $0.00618 |
| Opus 5 | $0.00014 | $0.00309 |
| Sonnet 5 | $0.00006 | $0.00124 |
| Haiku 4.5 | $0.00003 | $0.00062 |
Grade A, and why
video-downloader scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
Copies of this mod
3 near-identical copies found in the catalogue:
- video-downloader — 100% identical, 1 lines differ
- video-downloader — 100% identical, 1 lines differ
- video-downloader — 100% identical, 1 lines differ
How it starts
The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Video Downloader
This skill downloads videos from YouTube and other platforms directly to your computer.
When to Use This Skill
- Downloading YouTube videos for offline viewing
- Saving educational content for reference
- Archiving important videos
- Getting video files for editing or repurposing
- Downloading your own content from platforms
- Saving conference talks or webinars
What This Skill Does
- Downloads Videos: Fetches videos from YouTube and other platforms
- Quality Selection: Lets you choose resolution (480p, 720p, 1080p, 4K)
- Format Options: Downloads in various formats (MP4, WebM, audio-only)
- Batch Downloads: Can download multiple videos or playlists
- Metadata Preservation: Saves title, description, and thumbnail
How to Use
Basic Download
Download this YouTube video: https://youtube.com/watch?v=...
Download this video in 1080p quality
Audio Only
Download the audio from this YouTube video as MP3
Playlist Download
Download all videos from this YouTube playlist: [URL]
Batch Download
Download these 5 YouTube videos:
1. [URL]
2. [URL]
...
Example
User: "Download this YouTube video: https://youtube.com/watch?v=abc123"
Output:
Downloading from YouTube...
Video: "How to Build Products Users Love"
Channel: Lenny's Podcast
Duration: 45:32
Quality: 1080p
Progress: ████████████████████ 100%
✓ Downloaded: how-to-build-products-users-love.mp4
✓ Saved thumbnail: how-to-build-products-users-love.jpg
✓ Size: 342 MB
Saved to: ~/Downloads/
Inspired by: Lenny's workflow from his newsletter
Important Notes
⚠️ Copyright & Fair Use
- Only download videos you have permission to download
- Respect copyright laws and platform terms of service
- Use for personal, educational, or fair use purposes
- Don't redistribute copyrighted content
Tips
- Specify quality if you need lower file size (720p vs 1080p)
- Use audio-only for podcasts or music to save space
- Download to a dedicated folder to stay organized
- Check file size before downloading on slow connections
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 12d ago First seen · 106 lines · 28 tokens per session scan A f06e034ef673
video-downloader is a skill published in the GitHub repository happycapy-ai/Happycapy-skills (139 stars, last pushed 9d ago), licensed MIT. It adds 28 tokens to every session and 618 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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