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 ishands/upstack --skill start-coursegit clone --depth 1 https://github.com/ishands/upstackWrote 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/ishands/upstack/start-course)<a href="https://agentmods.dev/skills/ishands/upstack/start-course"><img src="https://agentmods.dev/badge/skills/ishands/upstack/start-course/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/ishands/upstack/start-course"><img src="https://agentmods.dev/badge/skills/ishands/upstack/start-course.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00060 | $0.01862 |
| Opus 5.5 | $0.00024 | $0.00745 |
| Sonnet 5.5 | $0.00012 | $0.00372 |
| Haiku 4.5 | $0.00006 | $0.00186 |
Grade A, and why
start-course 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 1mo 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.
The source is not reproduced here
A licence we could not identify
The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.
What ships with it
2 files 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.
- 1mo ago First seen · 238 lines · 60 tokens per session scan A fb119e5ad488
start-course is a skill published in the GitHub repository ishands/upstack (4 stars, last pushed 5mo ago), with no licence file. It adds 60 tokens to every session and 1,862 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-31.
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code-review-coach
Use when the learner wants to practise reviewing existing code, a diff, or a pull request through guided questioning — discovering and justifying findings one concern at a time instead of receiving a dumped list or a rewrite. The first non-DSA skill in this suite. Not for chasing an already-observed concrete failure…
specification-coach
Use when the learner has a vague feature request, issue, change request, or agent task and wants to turn it into an implementation-ready specification through guided questioning — clarifying observable behaviour, scope, non-goals, constraints, failure behaviour, acceptance criteria, and the smallest verifiable slice…
debug-coach
Use when the learner already has written code or pseudocode, knows what it should do, and it isn't doing that — and they want the bug isolated without receiving a rewritten solution. Not for choosing an approach (use dsa-tutor), not for tracing an approach that has no code yet (use dry-run-coach), and not for plain…
dsa-tutor
Use when the user is working through a DSA or LeetCode-style problem and wants to build real problem-solving ability instead of receiving a finished solution. Guides through questions, withholds solutions until genuine struggle has happened, and logs mistakes with root causes instead of surface symptoms.
pattern-transfer-coach
Use after the learner has solved or substantially completed a DSA problem and wants to turn it into transferable knowledge — abstracting the structure away from the story, naming signals that suggest or rule out the pattern, and adapting it to exactly one cousin problem. Not for solving the original problem…