extend-skillset SKILL.md skillA

This file is byte-identical to the first copy the registry indexed. Same content hash, so the same checks give both the same grade.

extend-skillset from velimirmueller/claude-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned
mdr add velimirmueller/claude-skills/extend-skillset@git:20261009.50bfdb9

Pins git:20261009.50bfdb9 in mdr.lock. Pin the fingerprint instead.

Audit grade
A, 17 of 17 checks passed
Kind
SKILL.md skill
Repository
velimirmueller/claude-skills
Path
skills/core/extend-skillset/SKILL.md
Versions recorded
1
Latest version
git:20261009.50bfdb9, committed Oct 9, 2026
Size
4,355 bytes
Repository stars
5
License
MIT

Use when the stack profile names a tool no installed skill covers, or the user asks for a new skill. Authors one in the house style, audit-first and profile-aware, into the project's .claude/skills or this plugin repo, then checks it.

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

# Extend Skillset

Turns "no skill covers X" into a skill that fits the set. Template and checklist: [skill-template.md](skill-template.md). House style: this repo's `CONTRIBUTING.md`.

## 1. Audit (change nothing)

```bash
cat .claude/stack-profile.md 2>/dev/null
ls .claude/skills 2>/dev/null; ls skills/*/ 2>/dev/null | head -80
grep -rli "<tool or topic>" .claude/skills skills 2>/dev/null | head
```

Answer three questions before writing anything:

1. Is there already a skill that covers it (even partly)? Extend that one; do not add a twin.
2. Is the gap a *procedure* with a trigger ("when X, do Y")? If it is only a fact, add it to a reference file or `_shared/` instead.
3. Is the stack stable enough to encode? A tool in the "Assess" ring of [tech-radar.md](../_shared/tech-radar.md) gets a short skill with a warning, not a full one.

## 2. Decide

| Situation | Action |
|---|---|
| Existing skill covers it | Edit it; add the case; stop. |
| Fact only | Add a rule to the nearest reference file; stop. |
| New procedure | Continue. |

Choose the destination (ask once with `AskUserQuestion`, recommended first):
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint
mdr add velimirmueller/claude-skills/extend-skillset@sha256:2a0047f0c4d9fd21

The line at the top of this page pins the label git:20261009.50bfdb9, 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.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_dpoczvtmfh2n24jl.svg)](https://markdownregistry.com/a/art_dpoczvtmfh2n24jl)

1 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 1 version of this file, committed on Oct 9, 2026.

versioncommittedcommitsizeaudit
git:20261009.50bfdb9 latest2026-10-09 50bfdb9 4,355 BA view

Audit of the latest version

A  17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the 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 (4355 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

velimirmueller/claude-skills · 5 stars · license MIT · pushed 2026-10-12 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_dpoczvtmfh2n24jl
GET https://markdownregistry.com/api/v1/resolve?ref=velimirmueller/claude-skills/extend-skillset
GET https://markdownregistry.com/api/v1/blob/2a0047f0c4d9fd214835ec2faa3286f6fb55431f691b902b2fa8b4929d0dc979

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.

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Every file in velimirmueller/claude-skills

Other files named extend-skillset

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git:20261009.50bfdb9 · audit A · 5 stars

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