What is update-skill?

A workflow for creating, updating, or removing reusable AI skill templates. Skills are saved instructions that an AI can run as commands or invoke automatically.

It helps find related skills, create skill folders and SKILL.md files, update templates, and remove obsolete skills.

It helps determine whether an existing skill should be changed or a new one created, while keeping the required files and settings consistent.

update-skill — Skill for Claude Code by fabis94/universal-ai-config

Install

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.

Any agent

npx skills add fabis94/universal-ai-config --skill update-skill

Clone the repo

git clone --depth 1 https://github.com/fabis94/universal-ai-config

Made for: Claude Code.

Wrote 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/fabis94/universal-ai-config/update-skill/github.svg)](https://agentmods.dev/skills/fabis94/universal-ai-config/update-skill)

Your own site

<a href="https://agentmods.dev/skills/fabis94/universal-ai-config/update-skill"><img src="https://agentmods.dev/badge/skills/fabis94/universal-ai-config/update-skill/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/fabis94/universal-ai-config/update-skill"><img src="https://agentmods.dev/badge/skills/fabis94/universal-ai-config/update-skill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 733 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

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	$0.00033	$0.00733
Opus 5.5	$0.00013	$0.00293
Sonnet 5.5	$0.00007	$0.00147
Haiku 4.5	$0.00003	$0.00073

Measured yesterday against content hash b8ce61d7aa4c, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

update-skill 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 yesterday.

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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

update-skill — 86% identical, 60 lines differ

.universal-ai-config/skills/update-skill/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Manage Skill Templates

Skills are reusable actions or workflows invocable as slash commands or auto-triggered by the AI.

Finding Existing Skills

List directories in <%= skillTemplatePath() %>/ to discover existing skills. Each skill is a directory containing a SKILL.md file. Read the SKILL.md frontmatter to understand what each skill does.

Deciding What to Do

Create new: when the task/workflow is distinct from existing skills
Update existing: when a skill covers similar ground but needs changes — modify its SKILL.md or supporting files
Delete: remove the entire skill directory when a skill is obsolete, then run uac generate --clean so its output goes too

Creating a New Skill

Create a directory: <%= skillTemplatePath() %>/{skill-name}/
Create SKILL.md inside it with frontmatter and instructions
Optionally add supporting files (templates, scripts, examples) in the same directory

Frontmatter Fields

Key fields: name (must match the folder name: lowercase letters, digits and hyphens, at most 64 characters), description (required), disableAutoInvocation, userInvocable, allowedTools, skillPaths, model, hooks, metadata (string values only), codex. uac warns when a skill breaks these Agent Skills spec rules. Every field with its per-target support: <%= docPath('uac/frontmatter') %>. Per-target override syntax: <%= docPath('uac/templates') %>.

Codex-specific UI metadata

For Codex-only UI metadata (display name, icons, brand color, invocation policy, MCP tool dependencies), use the nested codex.* frontmatter object. uac emits a sidecar agents/openai.yaml next to SKILL.md automatically when any codex.* field — or disableAutoInvocation — is set. The full codex.* key list is in <%= docPath('uac/frontmatter') %>.

Supporting Files

Skills can include additional files in their directory. These are automatically copied to generated output during uac generate. .md extra files are rendered through EJS (with access to target, config, path helpers), while non-.md files are copied byte for byte, executable bit included.

Read the full file on GitHub · 67 lines

Changes

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.

yesterday Changed b8ce61d7aa4c
2d ago Changed cf50d195cfa5
2mo ago First seen · 67 lines · 33 tokens per session scan A bd4c25a653ec

Subscribe to this mod's changes

update-skill is a skill published in the GitHub repository fabis94/universal-ai-config (14 stars, last pushed 2d ago), licensed MIT. It adds 33 tokens to every session and 733 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.

Building agents

update-skill next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
update-skillfabis94/universal-ai-config	Skill	14	2d ago	MIT	A	33	Claude Code
imagegenopenai/codex	Skill	134k	today	Apache-2.0	A	113	Codex
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	today	MIT	A	200	Claude Code, Codex
playwright-climicrosoft/playwright	Skill	99k	today	Apache-2.0	A	19	Claude Code
systematic-debuggingobra/superpowers	Skill	314k	3d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code
chat-pet-sprite-creationmicrosoft/vscode	Skill	195k	today	MIT	A	53	Claude Code, Codex