skill-loader

skill-loader is a skill for Claude Code, Codex from williamzujkowski/standards. It costs 25 tokens per session (454 once invoked), scanned A, original, MIT.

A guide to building and maintaining a loader for reusable agent skills. It covers implementation patterns, input validation, error handling, logging, performance, documentation, and testing.

In plain words
What is it for?
Use it when designing a skill loader, handling failures, validating inputs, adding logs, documenting interfaces, and writing unit or integration tests for the loader.
Why use it?
It helps make skill-loading code more consistent, maintainable, and safer to change. It also points out common implementation and testing concerns.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when designing a skill loader, handling failures, validating inputs, adding logs, documenting interfaces, and writing unit or integration tests for the loader.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/williamzujkowski/standards/skill-loader
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 williamzujkowski/standards --skill skill-loader
Clone the repo
git clone --depth 1 https://github.com/williamzujkowski/standards

Made for: Claude Code, Codex.

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.

agentmods badge for skill-loader

README.md
[![agentmods](https://agentmods.dev/badge/skills/williamzujkowski/standards/skill-loader/github.svg)](https://agentmods.dev/skills/williamzujkowski/standards/skill-loader)
Your own site
<a href="https://agentmods.dev/skills/williamzujkowski/standards/skill-loader"><img src="https://agentmods.dev/badge/skills/williamzujkowski/standards/skill-loader/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.

agentmods 80×15 button for skill-loader

Your own site · 80×15
<a href="https://agentmods.dev/skills/williamzujkowski/standards/skill-loader"><img src="https://agentmods.dev/badge/skills/williamzujkowski/standards/skill-loader.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 25 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 454 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.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00025 $0.00454
Opus 5.5 $0.00010 $0.00182
Sonnet 5.5 $0.00005 $0.00091
Haiku 4.5 $0.00003 $0.00045

Measured yesterday against content hash bc3c52f8181d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-30, from the pricing page.

Security

Grade A, and why

skill-loader 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.

skills/skill-loader/SKILL.md · 84 lines

What it actually says

Skill Loader

Quick Navigation: Level 1: Quick Start (5 min) → Level 2: Implementation (30 min) → Level 3: Mastery (Extended)


Level 1: Quick Start

Core Principles

  1. Best Practices: Follow industry-standard patterns for skill loader
  2. Security First: Implement secure defaults and validate all inputs
  3. Maintainability: Write clean, documented, testable code
  4. Performance: Optimize for common use cases

Essential Checklist

  • Follow established patterns for skill loader
  • Implement proper error handling
  • Add comprehensive logging
  • Write unit and integration tests
  • Document public interfaces

Quick Links to Level 2


Level 2: Implementation

Core Concepts

This skill covers essential practices for skill loader.

Key areas include:

  • Architecture patterns
  • Implementation best practices
  • Testing strategies
  • Performance optimization

Implementation Patterns

Apply these patterns when working with skill loader:

  1. Pattern Selection: Choose appropriate patterns for your use case
  2. Error Handling: Implement comprehensive error recovery
  3. Monitoring: Add observability hooks for production

Common Pitfalls

Avoid these common mistakes:

  • Skipping validation of inputs
  • Ignoring edge cases
  • Missing test coverage
  • Poor documentation

Level 3: Mastery Resources

Reference Materials

Templates

See the templates/ directory for starter configurations.

External Resources

Consult official documentation and community best practices for skill loader.

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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.

  1. yesterday First seen · 84 lines · 25 tokens per session scan A bc3c52f8181d

Subscribe to this mod's changes

skill-loader is a skill published in the GitHub repository williamzujkowski/standards (18 stars, last pushed 1mo ago), licensed MIT. It adds 25 tokens to every session and 454 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 2026-09-29.

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