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 zebbern/termstack --skill header-analysisgit clone --depth 1 https://github.com/zebbern/termstackWrote 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/zebbern/termstack/header-analysis)<a href="https://agentmods.dev/skills/zebbern/termstack/header-analysis"><img src="https://agentmods.dev/badge/skills/zebbern/termstack/header-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/zebbern/termstack/header-analysis"><img src="https://agentmods.dev/badge/skills/zebbern/termstack/header-analysis.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 | $0.00050 | $0.03864 |
| Opus 5.5 | $0.00020 | $0.01546 |
| Sonnet 5.5 | $0.00010 | $0.00773 |
| Haiku 4.5 | $0.00005 | $0.00386 |
Grade A, and why
header-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 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
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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.
- 1mo ago First seen · 474 lines · 50 tokens per session scan A eaff667adcf4
header-analysis is a skill published in the GitHub repository zebbern/termstack (4 stars, last pushed 6mo ago), with no licence file. It adds 50 tokens to every session and 3,864 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 2026-09-03.
Other skills, from other repositories
analyzing-web-application-http-headers
Analyze HTTP response headers for security misconfigurations including missing Content Security Policy, HSTS, X-Frame-Options, and information disclosure via Server/X-Powered-By headers. Covers manual inspection and automated scanning to identify header-based vulnerabilities and recommend remediations.
performing-security-headers-audit
Auditing HTTP security headers including CSP, HSTS, X-Frame-Options, and cookie attributes to identify missing or misconfigured browser-level protections.
ultra-adlc
End-to-end delivery orchestration for explicitly requested, very large software changes that must be completely implemented and independently proven. Use when the user invokes "ultra-adlc" or asks for an Ultra-ADLC-scale full delivery; do not use for ordinary features, small fixes, reviews, or ad hoc parallel work.
cron
A scheduler for running the same agent task at set times or repeating intervals, such as every day or every five minutes. It uses the standard five-part cron schedule format.
clarifying-questions
A requirements-clarification guide for situations where a request is vague, hides important assumptions, or may ask for the wrong solution.
debugging
A methodical way to find the underlying cause of software bugs by observing what happens, forming hypotheses, and testing them. It separates finding the cause from applying and checking the fix.