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 maystudios/claude-skills --skill anthropic-skilljar-extractorgit clone --depth 1 https://github.com/maystudios/claude-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/maystudios/claude-skills/anthropic-skilljar-extractor)<a href="https://agentmods.dev/skills/maystudios/claude-skills/anthropic-skilljar-extractor"><img src="https://agentmods.dev/badge/skills/maystudios/claude-skills/anthropic-skilljar-extractor/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/maystudios/claude-skills/anthropic-skilljar-extractor"><img src="https://agentmods.dev/badge/skills/maystudios/claude-skills/anthropic-skilljar-extractor.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 | $0.00107 | $0.00635 |
| Opus 5 | $0.00053 | $0.00318 |
| Sonnet 5 | $0.00021 | $0.00127 |
| Haiku 4.5 | $0.00011 | $0.00064 |
Grade A, and why
anthropic-skilljar-extractor 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 10d 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.
How it starts
The opening of the file, as written. The whole thing — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Anthropic Skilljar Course Extractor
Step 1: Run the Extraction Script
python3 scripts/extract_course.py \
<skilljar_url> <output_dir>
This produces:
<course-slug>/
├── README.md
├── 01-<section>/
│ ├── 01-<lesson>.md
│ └── ...
└── assets/images/ ← downloaded .webp diagrams
Step 2: Describe Diagrams
For each full-size .webp in assets/images/ (not -medium.webp):
- Use the
Readtool to view it visually - Add a detailed alt-text block and embed with
in the relevant lesson markdown
Assign images to lessons based on topic — architecture diagrams go in intro lessons, code screenshots in hands-on lessons, summary slides in review lessons.
Step 3: Enrich Lesson Markdown
The script embeds bullet-point notes. Expand each lesson file:
- Add proper
##headings per concept - Format code examples in fenced code blocks with language tags
- Convert "Key: value" lines to
**Key:** valuebold format - Add tables for comparisons (e.g., message types, primitives)
- Keep the frontmatter block (Section, URL, Lesson Type)
Step 4: Enhance README
Add to the auto-generated README:
- Full course description paragraph
- Key concepts reference table
- Quick-reference code snippets
- Diagram index with one-line descriptions per image
How the Script Works (for debugging)
- Fetches page HTML; extracts
window.__chatData(LLM notes embedded in every Skilljar page) - Parses sidebar
<ul class="dp-curriculum">for section/lesson structure - Downloads CloudFront images from
d7juhi4i8fsw0.cloudfront.net/images/<slug>/ - Deduplicates lessons by URL (curriculum HTML appears twice in page source)
- Fuzzy-matches notes to lessons by title similarity
If Login Is Required
Individual lesson pages always require auth — do not fetch them. If the course landing page itself requires login (script finds 0 lessons):
- Ask user to save the page HTML (browser → Save As → Webpage, HTML Only)
- Modify script's
fetch()toopen(path).read()and pass the local file
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.
- 10d ago First seen · 70 lines · 107 tokens per session scan A d4ea2e989d64
anthropic-skilljar-extractor is a skill published in the GitHub repository maystudios/claude-skills (22 stars, last pushed 26d ago), licensed MIT. It adds 107 tokens to every session and 635 once invoked, about $0.0005 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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