how SKILL.md skillA
how from backnotprop/pstack is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add backnotprop/pstack/how@git:20261020.e44668cPins git:20261020.e44668c in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- backnotprop/pstack
- Path
skills/how/SKILL.md- Versions recorded
- 13
- Latest version
- git:20261020.e44668c, committed Oct 20, 2026
- First version recorded
- May 27, 2026
- Size
- 3,258 bytes
- Repository stars
- 3,337
- License
- MIT
Use for "how does X work", code walkthroughs before changing something, and placement / ownership / layering questions ("where should this live", "which package owns this", "is this the right layer"). Explains subsystem architecture, runtime flow, onboarding mental models. Use why for motivation.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# How Explore the codebase to answer "how does X work?" questions. Produce architectural explanations at the level of a senior engineer onboarding onto a subsystem, enough to build a working mental model, not so much that it reads like annotated source code. Every spawn is a Task subagent with `subagent_type: generalPurpose` and `readonly: true`. Explorers use the `how explorer` line in the pstack settings file (`~/.cursor/rules/pstack-models.mdc` in Cursor, `~/.claude/rules/pstack-models.md` in Claude Code, `~/.agents/pstack-models.md` in other harnesses) (default `grok-4.7-xhigh-fast`), and every explainer uses the `how explainer` line (default `claude-opus-5-5-xhigh`). Set `model` to that line's value, or to the default if the file or the line is missing. Leave `model` unset when the value is `auto` or `inherit-parent`. If your subagent tool rejects a slug, use the default and say so. If it rejects the default, use the closest valid slug of the same family from its error message or your harness's model list. Pick each subagent's reasoning level and fast or standard speed for the job, per the Subagents section of the **poteto-mode** skill. ## 1. Assess complexity …
Read the whole file at its exact version.
How to install
mdr add backnotprop/pstack/how@sha256:a63ac90597960cfdThe line at the top of this page pins the label git:20261020.e44668c, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_t46bs6mtnxddxa23)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 13 versions of this file, between May 27, 2026 and Oct 20, 2026, about one every 12 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261020.e44668c latest | 2026-10-20 | e44668c | 3,258 B | A | view · diff |
| git:20261015.6f131f1 | 2026-10-15 | 6f131f1 | 3,207 B | A | view · diff |
| git:20261015.df856f4 | 2026-10-15 | df856f4 | 2,651 B | A | view · diff |
| git:20261012.fce11a3 | 2026-10-12 | fce11a3 | 3,074 B | A | view · diff |
| git:20261012.f3afb70 | 2026-10-12 | f3afb70 | 2,518 B | A | view · diff |
| git:20261008.1edf0a5 | 2026-10-08 | 1edf0a5 | 3,637 B | A | view · diff |
| git:20261008.4aed5af | 2026-10-08 | 4aed5af | 3,081 B | A | view · diff |
| git:20261004.124f622 | 2026-10-04 | 124f622 | 3,633 B | A | view · diff |
| git:20261004.c0c3f13 | 2026-10-04 | c0c3f13 | 3,077 B | A | view · diff |
| git:20260914.aa2db46 | 2026-09-14 | aa2db46 | 3,380 B | A | view · diff |
| git:20260914.55bfdc2 | 2026-09-14 | 55bfdc2 | 2,738 B | A | view · diff |
| git:20260819.4b32d9d | 2026-08-19 | 4b32d9d | 7,285 B | A | view · diff |
| git:20260527.b3eabf1 | 2026-05-27 | b3eabf1 | 7,690 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (3258 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
backnotprop/pstack · 3,337 stars · license MIT · pushed 2026-10-28 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_t46bs6mtnxddxa23 GET https://markdownregistry.com/api/v1/resolve?ref=backnotprop/pstack/how GET https://markdownregistry.com/api/v1/blob/a63ac90597960cfdc4d51ec88960b3bf0a05d44a7dff1d5a2b8639981c25ca54
Your AI assistant 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.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
More from backnotprop/pstack
Every file in backnotprop/pstack