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 26zl/cybersec-toolkit --skill constant-time-analysisgit clone --depth 1 https://github.com/26zl/cybersec-toolkitWrote 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/26zl/cybersec-toolkit/constant-time-analysis)<a href="https://agentmods.dev/skills/26zl/cybersec-toolkit/constant-time-analysis"><img src="https://agentmods.dev/badge/skills/26zl/cybersec-toolkit/constant-time-analysis/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/26zl/cybersec-toolkit/constant-time-analysis"><img src="https://agentmods.dev/badge/skills/26zl/cybersec-toolkit/constant-time-analysis.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Rogue Agent · line 141 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 144 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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 | $0.00067 | $0.02230 |
| Opus 5 | $0.00034 | $0.01115 |
| Sonnet 5 | $0.00013 | $0.00446 |
| Haiku 4.5 | $0.00007 | $0.00223 |
Grade A, and why
constant-time-analysis 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 5d 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 — 222 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Constant-Time Analysis
Analyze cryptographic code to detect operations that leak secret data through execution timing variations.
When to Use
User writing crypto code? ──yes──> Use this skill
│
no
│
v
User asking about timing attacks? ──yes──> Use this skill
│
no
│
v
Code handles secret keys/tokens? ──yes──> Use this skill
│
no
│
v
Skip this skill
Concrete triggers:
- User implements signature, encryption, or key derivation
- Code contains
/or%operators on secret-derived values - User mentions "constant-time", "timing attack", "side-channel", "KyberSlash"
- Reviewing functions named
sign,verify,encrypt,decrypt,derive_key
When NOT to Use
- Non-cryptographic code (business logic, UI, etc.)
- Public data processing where timing leaks don't matter
- Code that doesn't handle secrets, keys, or authentication tokens
- High-level API usage where timing is handled by the library
Language Selection
Based on the file extension or language context, refer to the appropriate guide:
| Language | File Extensions | Guide |
|---|---|---|
| C, C++ | .c, .h, .cpp, .cc, .hpp |
references/compiled.md |
| Go | .go |
references/compiled.md |
| Rust | .rs |
references/compiled.md |
| Swift | .swift |
references/swift.md |
| Java | .java |
references/vm-compiled.md |
| Kotlin | .kt, .kts |
references/kotlin.md |
| C# | .cs |
references/vm-compiled.md |
| PHP | .php |
references/php.md |
| JavaScript | .js, .mjs, .cjs |
references/javascript.md |
| TypeScript | .ts, .tsx |
references/javascript.md |
| Python | .py |
references/python.md |
| Ruby | .rb |
references/ruby.md |
What ships with it
12 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.
- ct_analyzer/__init__.py 984 B runs code
- ct_analyzer/analyzer.py 50 KB runs code
- ct_analyzer/script_analyzers.py 125 KB runs code
- README.md 3.8 KB
- references/compiled.md 4.0 KB
- references/javascript.md 4.3 KB
- references/kotlin.md 6.6 KB
- references/php.md 4.7 KB
- references/python.md 5.1 KB
- references/ruby.md 5.3 KB
- references/swift.md 8.0 KB
- references/vm-compiled.md 10 KB
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.
- 5d ago First seen · 222 lines · 67 tokens per session scan A a68f05986334
constant-time-analysis is a skill published in the GitHub repository 26zl/cybersec-toolkit (51 stars, last pushed yesterday), licensed MIT. It adds 67 tokens to every session and 2,230 once invoked, about $0.0003 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 2026-09-03.
Other skills, from other repositories
implementing-github-advanced-security-for-code-scanning
Configure GitHub Advanced Security with CodeQL to perform automated static analysis and vulnerability detection across repositories at enterprise scale.
appsec-code-review
../../../appsec-devsecops/appsec-code-review/SKILL.md.
security-review
Security review workflow for a PR, feature or codebase — scope, automated scans, manual OWASP/CWE pattern-check, prioritize and report. Uses secure-coding as pattern library.
sast-orchestrator
SAST orchestration for Semgrep, CodeQL and SonarQube. Covers tool selection, ruleset curation, PR-comment integration, noise reduction with baselines, and language-specific linters (bandit, gosec, brakeman, eslint-security) when they add coverage.
verification-loop
Structured red-team pass over your own output — surface assumptions, gaps, failure modes and security red flags before shipping.
mobile-pentest
Mobile app pentest for bug bounty (Android APK + iOS IPA) — runtime-first workflow: install app, proxy through Burp/mitmproxy, drive the UI, capture packets, then test the API exactly like a web target; escalate to decompile (apktool/jadx) and Frida/objection only when traffic is SSL-pinned, encrypted, or absent.…