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 tonydzi/second-brain-starter-kit --skill secrets-in-git-historygit clone --depth 1 https://github.com/tonydzi/second-brain-starter-kitWrote 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/tonydzi/second-brain-starter-kit/secrets-in-git-history)<a href="https://agentmods.dev/skills/tonydzi/second-brain-starter-kit/secrets-in-git-history"><img src="https://agentmods.dev/badge/skills/tonydzi/second-brain-starter-kit/secrets-in-git-history/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/tonydzi/second-brain-starter-kit/secrets-in-git-history"><img src="https://agentmods.dev/badge/skills/tonydzi/second-brain-starter-kit/secrets-in-git-history.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 | $0.00082 | $0.03237 |
| Opus 5.5 | $0.00033 | $0.01295 |
| Sonnet 5.5 | $0.00016 | $0.00647 |
| Haiku 4.5 | $0.00008 | $0.00324 |
Grade A, and why
secrets-in-git-history scanned grade A 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 11d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -s https://github.com/example-org/example-repo/commit/<sha>.patch | head -5 This is a copy
89% identical to secrets-in-git-history — 31 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 262 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Secrets in git history
A repository is three intelligence products: a list of humans with real email addresses, a map of the organisation's infrastructure, and a credential store nobody meant to publish. The costly mistake is scanning the working tree. Secrets deleted from HEAD stay in history forever, and commits deleted from a branch stay reachable through the fork network — scan only what is checked out and you are searching the one place the secret was definitely removed from.
What you're holding, and where to start
| You have | Start with | Why |
|---|---|---|
| An organisation name | Public org members, then their personal repos | Corporate repos are reviewed; personal ones are not |
| A developer's name or handle | Commit emails across their repos | Yields an email nothing else gives you |
| A commit email | Reverse-search across hosts; resolve any noreply ID | Links accounts across orgs and platforms |
| A suspected credential leak | Both scanners over a mirror clone, all refs | HEAD-only scanning misses the point entirely |
| A specific string — hostname, key prefix | git log -S pickaxe across all refs |
Tells you when it entered and when it left |
| A live domain | Check for an exposed .git — see the legal note |
Full history from a web server, if authorized |
| Nothing but a company website | Code search the org's internal domain names | Finds repos with no obvious link to the org |
The commit email leak
Git records an author identity on every commit, self-asserted rather than verified. That cuts both ways: emails are trivially forged, and they are also the most reliable public link between a code-host identity and a real mailbox.
git clone --mirror https://github.com/example-org/example-repo.git repo.git
git --git-dir=repo.git log --all --format='%an <%ae>' | sort -u
GitHub's web UI does not display commit emails, which leads people to assume
they are hidden. They are not. Append .patch to any commit URL for a
mail-format patch whose From: header carries the author name and email; the
API returns the same under commit.author.email.
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.
- 11d ago Changed · -1 lines 4ac0ccf41b9d
- 16d ago First seen · 263 lines · 82 tokens per session scan A 022506b95004
secrets-in-git-history is a skill published in the GitHub repository tonydzi/second-brain-starter-kit (9 stars, last pushed today), licensed MIT. It adds 82 tokens to every session and 3,237 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). It is 89% identical to secrets-in-git-history, differing in 31 lines, and is treated as a copy.
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