Home / stevepolitodesign / skills · diff-explainer/SKILL.md · GitHub

diff-explainer skillA

diff-explainer is agent-read markdown (skill) from stevepolitodesign/skills: Builds a shareable HTML walkthrough of the current changes, highlighting risks, tradeoffs, and alternatives considered..

Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.

What the file says

# Diff explainer

The diff already shows what changed. What it can't show is why — why this approach
and not the obvious one, what broke when you tried that, what you're nervous about,
what you decided not to do. Supply that. Your reader is a sharp, time-poor Rails
developer who knows Rails and Heroku well and this stack barely.

## 1. Work out what you're explaining

No argument means the current branch against its base, diffed from the merge base
so other people's commits don't leak in.

```bash
BASE=$(git rev-parse --verify --quiet @{upstream} \
    || git rev-parse --verify --quiet refs/remotes/origin/HEAD \
    || git rev-parse --verify --quiet refs/heads/main \
    || git rev-parse --verify --quiet refs/heads/master)
MB=$(git merge-base "$BASE" HEAD)
test -n "$MB" || echo "No base found — ask which branch to diff against."
git diff --stat "$MB" && git log --oneline "$MB"..HEAD
git status --porcelain -uall   # untracked files the diff won't show
```

Size up the change from the stat before reading `git diff "$MB"` — a diff you pull
into context whole is one you can no longer decide to skip. Upstream first, and
…

Read the whole file at its exact version.

How to install

Latest version
mdr add stevepolitodesign/skills/diff-explainer@git:20260924.62cef2e
Exact content
mdr add stevepolitodesign/skills/diff-explainer@sha256:185fd4c1d01e5b6e

Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_ragu4ufhigopuqn3.svg)](https://markdownregistry.com/a/art_ragu4ufhigopuqn3)

1 badge views in 30 days

Versions

versioncommittedcommitsizeaudit
git:20260924.62cef2e latest2026-09-24 62cef2e 9,418 BA view · diff
git:20260915.6a514262026-09-15 6a51426 7,761 BA view · diff
git:20260818.c4a44662026-08-18 c4a4466 7,792 BA view · diff
git:20260817.f458aea2026-08-17 f458aea 6,371 BA view

Audit of the latest version

A  17 of 17 checks passed. Deterministic, no model, same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (9418 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

stevepolitodesign/skills · 3 stars · license none · pushed 2026-09-24 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_ragu4ufhigopuqn3
GET https://markdownregistry.com/api/v1/resolve?ref=stevepolitodesign/skills/diff-explainer
GET https://markdownregistry.com/api/v1/blob/185fd4c1d01e5b6e3bd679e9184d0c12d06cf08b0d543a4a3ec9cd14ed3adb21

Your agent does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

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Every file in stevepolitodesign/skills

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