ship-a-detector SKILL.md skillA
ship-a-detector from edbertchan/catstack is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add edbertchan/catstack/ship-a-detector@git:20260911.cf2f81fPins git:20260911.cf2f81f in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- edbertchan/catstack
- Path
product/skills/ship-a-detector/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260911.cf2f81f, committed Sep 11, 2026
- First version recorded
- Sep 10, 2026
- Size
- 2,358 bytes
- Repository stars
- 6
- License
- none declared
Author a hook or gate detector end to end: the seven defect kinds this repo keeps re-shipping, then the install, test, README, and inventory wiring a detector is not finished without. Trigger before writing or widening anything under engine/hooks/ or a scripts/check_*.py gate — a new PreToolUse/Stop/UserPromptSubmit hook, a new detector inside an existing hook, or a regex change to one that already ships.
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
# ship-a-detector Use this before writing or widening a detector — a hook under `engine/hooks/`, or a CI gate under `scripts/check_*.py`. Both decide "does this input match the bad thing", and both break the same seven ways here. ## Why this exists Measured on this repo's own history: 65 of 185 merged PRs touch `engine/hooks/`, 13 of 28 hooks needed post-ship repair, and 37 PRs did nothing but repair a shipped detector. `diu-stop` took 8, `pr-schema-gate` 7, `wrong-check-reflect` 6, `scope-lock` 4. `gh-write-verification` hit two separate known kinds in three days. None of those were new problems; each was a kind already fixed in another hook. ## The playbook Open [playbooks/detector-lifecycle.md](playbooks/detector-lifecycle.md) before any task-specific work and copy the 20-line block under **The list** into your todolist, verbatim. Each line says what "done" means for its step. Then work it top to bottom, using the numbered sections below the block for how. A step that does not apply stays in the list marked `skip: <reason>` — deleting it is how a kind gets re-shipped. The same list covers both jobs. A new hook works every step. A widening of …
Read the whole file at its exact version.
How to install
mdr add edbertchan/catstack/ship-a-detector@sha256:e948f58e96fa0122The line at the top of this page pins the label git:20260911.cf2f81f, 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_xjf74hbcm627uu4y)
1 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Sep 10, 2026 and Sep 11, 2026, more than one a day.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260911.cf2f81f latest | 2026-09-11 | cf2f81f | 2,358 B | A | view · diff |
| git:20260911.28f750a | 2026-09-11 | 28f750a | 2,256 B | A | view · diff |
| git:20260910.e23737a | 2026-09-10 | e23737a | 2,275 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 (2358 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
edbertchan/catstack · 6 stars · license none declared · pushed 2026-10-22 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_xjf74hbcm627uu4y GET https://markdownregistry.com/api/v1/resolve?ref=edbertchan/catstack/ship-a-detector GET https://markdownregistry.com/api/v1/blob/e948f58e96fa012289a4dfe4c7d443a4f53b1f60c3a2c2ef743f2ae55334dd9c
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.