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 tomsej/pi-ext --skill pr-explaingit clone --depth 1 https://github.com/tomsej/pi-extWrote 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/tomsej/pi-ext/pr-explain)<a href="https://agentmods.dev/skills/tomsej/pi-ext/pr-explain"><img src="https://agentmods.dev/badge/skills/tomsej/pi-ext/pr-explain/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/tomsej/pi-ext/pr-explain"><img src="https://agentmods.dev/badge/skills/tomsej/pi-ext/pr-explain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00036 | $0.00744 |
| Opus 5.5 | $0.00014 | $0.00298 |
| Sonnet 5.5 | $0.00007 | $0.00149 |
| Haiku 4.5 | $0.00004 | $0.00074 |
Grade A, and why
pr-explain 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.
How it starts
The opening of the file, as written. The whole thing — 49 lines — stays where its author put it; the contents beside it link to each section on GitHub.
PR Explain
Generate an accurate English explanation of one PR. Read the repository; never modify it.
Read the PR
Input: PR number or URL.
- Metadata:
gh pr view <n> --json title,body,baseRefName,headRefOid,url. - Changes and evidence:
gh pr diff <n>andgh pr checks <n>. - Fetch without checkout:
git fetch origin pull/<n>/head; inspect files withgit show FETCH_HEAD:<path>. - Read callers and surrounding code, not only the diff.
- Treat PR claims as claims: confirm each with code, tests, or CI; mark unsupported claims ⚠️.
Write the explanation
Save ~/Workspace/specs/<project>/pr-<n>-<slug>/explanation.md; derive project, number, and slug—never guess them.
Use these sections in order:
- Background — optional newcomer context, then the specific problem.
- Intuition — the core idea with small example data.
- Change top to bottom — one causal architecture/code walkthrough.
- Claims and evidence — claim, user-visible result, exact test/check evidence.
- Try it yourself — disposable setup and observable checklist items
- [ ]. - Quiz — five useful multiple-choice questions.
Change map
Use closed <details> blocks: <code>PRINCIPLE</code> → <code>FLOW</code> → <code>STEP</code> → <code>KEPT</code> → <code>VERIFY</code>.
Each <summary> must stand alone: label, short title, one-sentence conclusion.
Inside STEP, include only important files: 🟡 <a href="<diff-url>"><code>MODIFIED</code></a> or 🟢 <a href="<diff-url>"><code>NEW</code></a>.
Make the file name a permalink to exact HEAD lines: .../blob/<sha>/<path>#Lx-Ly.
Show a short final-code snippet fenced with the language of the source file; link to the diff instead of pasting raw diff headers.
Skip lockfiles, generated files, mechanical edits, and repeated prose.
Format
Write Markdown only. Use small mermaid diagrams with example data; no ASCII diagrams.
Use exact symbol, test, and file names. Unknown facts are — or ⚠️, never inventions.
Quiz answers must render inside raw HTML: <details><summary>Answer</summary><p><strong>B.</strong> Why it is right and the others are wrong.</p></details>.
Print the absolute output path.
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 · 49 lines · 36 tokens per session scan A de44547e511b
pr-explain is a skill published in the GitHub repository tomsej/pi-ext (79 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 744 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 2026-08-30.
Other skills, from other repositories
pr
Draft a PR body from OMC's paper trail — the smallest visual that proves the change, evidence consumed from the verify protocol (never re-collected), reversibility from the ADR test on the diff, glossary language throughout.
merge-batch
Prepare and merge an owner-selected PR batch with contributor credit and exact-candidate admission. Use for a pasted PR list; combined focused validation is diagnostic, and every actual landing still requires its applicable checks and authorization.
otto-pr-review-loop
Run Polly and OCR on a PR until all findings settle.
engram-branch-pr
PR creation workflow for Engram following the issue-first enforcement system. Trigger: When creating a pull request, opening a PR, or preparing changes for review.
github-contributor
A step-by-step guide for contributing code, tests, documentation, or build changes to open-source projects you do not maintain. It explains how to prepare a pull request that follows the project’s rules and is easier for maintainers to review.
revdiff
Review diffs, files, and documents with inline annotations in a TUI overlay, or answer questions about revdiff usage, configuration, themes, and keybindings. Opens revdiff in agterm/tmux/zellij/herdr/kitty/wezterm/cmux/ghostty/iterm2/emacs-vterm, captures annotations, and addresses them. Works in git, hg, and jj repos…