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.
npx skills add TechDufus/oh-my-claude --skill writing-skillsgit clone --depth 1 https://github.com/TechDufus/oh-my-claudeWrote 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.
[](https://agentmods.dev/skills/techdufus/oh-my-claude/writing-skills)<a href="https://agentmods.dev/skills/techdufus/oh-my-claude/writing-skills"><img src="https://agentmods.dev/badge/skills/techdufus/oh-my-claude/writing-skills/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.
<a href="https://agentmods.dev/skills/techdufus/oh-my-claude/writing-skills"><img src="https://agentmods.dev/badge/skills/techdufus/oh-my-claude/writing-skills.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Rogue Agent · line 3 Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
- high Rogue Agent · line 39 Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
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 | $0.00052 | $0.01148 |
| Opus 5 | $0.00026 | $0.00574 |
| Sonnet 5 | $0.00010 | $0.00230 |
| Haiku 4.5 | $0.00005 | $0.00115 |
Grade A, and why
writing-skills 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 12d ago.
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.
How it starts
The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Writing Skills Skill
TDD applied to process documentation.
Core Principle
Writing skills IS TDD applied to process documentation. If you can't test it breaks without the skill, the skill isn't needed.
When to Apply
- Creating new skills
- Editing existing skills
- Reviewing skill quality
- Authoring plugin components
TDD Mapping
| TDD Concept | Skill Equivalent |
|---|---|
| Test case | Pressure scenario (situation where agent fails without skill) |
| Production code | SKILL.md content |
| Failing test | Agent demonstrably fails the scenario |
| Passing test | Agent handles scenario correctly with skill loaded |
| Refactor | Trim to minimum effective content |
RED-GREEN-REFACTOR for Skills
RED: Identify Failure Scenarios
Identify 3+ pressure scenarios where the agent fails without this skill. Document the failure mode. This is your test suite. If you can't find 3 scenarios, the skill probably isn't needed.
GREEN: Write Minimum Effective Content
Write SKILL.md that addresses every identified failure. Minimum content to pass -- no extras, no nice-to-haves, no "comprehensive guides." Every section must map to at least one pressure scenario.
REFACTOR: Trim Aggressively
Remove anything that doesn't directly address a pressure scenario. Target ~120 lines. If removing a line doesn't weaken any pressure scenario, remove it.
SKILL.md Structure Template
---
name: {short-name}
description: "{Role sentence}. Use when {triggers}. Triggers on: {keywords}."
---
# {Name} Skill
{Tagline}
## When to Apply
## Core Pattern / Framework
## Anti-Rationalization Table (if methodology skill)
## Common Mistakes
## The Bottom Line
Claude Search Optimization (CSO)
The description field determines when Claude loads your skill. Get it wrong and the skill never fires.
- Description = "Use when..." triggers ONLY
- NEVER summarize the workflow in the description
- Include trigger keywords that match how users/agents naturally phrase the need
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.
- 12d ago First seen · 144 lines · 52 tokens per session scan A 1b62d15fb563
writing-skills is a skill published in the GitHub repository TechDufus/oh-my-claude (176 stars, last pushed 2mo ago), licensed MIT. It adds 52 tokens to every session and 1,148 once invoked, about $0.0003 per session on Opus 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.
Other skills, from other repositories
taiyi-dev
A software-development stage that implements planned tasks using test-driven development, or TDD: write a failing test, make it pass, then improve the code. It checks the task plan, dependencies, file boundaries, and required completion evidence.
test-generation
Use when the user asks for tests, mentions TDD, or when new code has been written and needs test coverage.
setup
Set up or update TDD Guard for the current project. Detects the test framework, installs or updates the matching reporter, and configures or migrates its configuration to match the current specification.
taiyi-test
A project workflow skill for verifying an implementation and producing a TEST.md record. TDD means writing a failing test, implementing the change, and then making the test pass; this skill checks that process and other regression cases.
superpowers
Use when the user wants a disciplined software development workflow with design-first planning, implementation plans, TDD, systematic debugging, code review, or verification-before-completion, adapted from obra/superpowers.
django-tdd
Django testing strategies with pytest-django, TDD methodology, factoryboy, mocking, coverage, and testing Django REST Framework APIs.