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 agentmods add skills/netopsengineer/agent-skill-description-optimizer/skillnpx skills add netopsengineer/agent-skill-description-optimizer --skill skillgit clone --depth 1 https://github.com/netopsengineer/agent-skill-description-optimizerWhat 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 | $0.00016 | $0.00238 |
| Opus 5 | $0.00008 | $0.00119 |
| Sonnet 5 | $0.00003 | $0.00048 |
| Haiku 4.5 | $0.00002 | $0.00024 |
Grade C, and why
e2e-fixture-skill scanned grade C with 1 finding 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 2d 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.
Hidden instructionshighPrompt injection
Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.
<!-- Regression fixture for AGENTS.md's "Integration test" section. The generic `name:` and deliberately vague `description:` above are load-bearing: they keep the triggering baseline well below 1.0 (verified: single-mod What it actually says
E2E Fixture Skill
Break down a regular expression into its component parts and explain what each part matches. Use this when a user has a regex that isn't behaving as expected, or wants to understand/document an existing pattern.
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.
- 2d ago First seen · 23 lines · 16 tokens per session scan C 51207fb50576
e2e-fixture-skill is a skill published in the GitHub repository netopsengineer/agent-skill-description-optimizer (2 stars, last pushed 4d ago), licensed MIT. It adds 16 tokens to every session and 238 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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