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 hamzabellouch/agent-skills --skill set-theorygit clone --depth 1 https://github.com/hamzabellouch/agent-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/hamzabellouch/agent-skills/set-theory)<a href="https://agentmods.dev/skills/hamzabellouch/agent-skills/set-theory"><img src="https://agentmods.dev/badge/skills/hamzabellouch/agent-skills/set-theory/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/hamzabellouch/agent-skills/set-theory"><img src="https://agentmods.dev/badge/skills/hamzabellouch/agent-skills/set-theory.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 | $0.00024 | $0.00221 |
| Opus 5.5 | $0.00010 | $0.00088 |
| Sonnet 5.5 | $0.00005 | $0.00044 |
| Haiku 4.5 | $0.00002 | $0.00022 |
Grade A, and why
set-theory 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 7d 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.
What it actually says
Set Theory
Domain
Foundations of mathematics via sets.
Core Concepts
- Sets, subsets, power sets
- Unions, intersections, complements
- Relations, functions, orderings
- Cardinality, countability
- Axiom of Choice, ZFC
Key Methods
- Cantor's diagonal argument
- Transfinite induction
- Ordinals and cardinals
- Forcing (advanced)
Canonical Examples
- |ℕ| = |ℚ| < |ℝ|.
- Power set of S has 2^{|S|} elements.
- Russell's paradox: no set of all sets.
Common Pitfalls
- Naive comprehension leads to paradoxes
- Confusing ∈ with ⊆
- Assuming AC always holds constructively
Related Skills
Logic, Topology, Category Theory
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.
- 7d ago First seen · 38 lines · 24 tokens per session scan A 2d20c8f6e60a
set-theory is a skill published in the GitHub repository hamzabellouch/agent-skills (8 stars, last pushed today), licensed MIT. It adds 24 tokens to every session and 221 once invoked, about $0.0001 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 2026-10-10.
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