write-documentation

A documentation-writing guide for Cratis projects that uses Diátaxis, a method for separating tutorials, how-to guides, reference pages, and explanations.

In plain words
What is it for?
Classifying documentation, drafting Astro Starlight Markdown or MDX pages, and following Cratis terminology and formatting rules.
Why use it?
It helps choose the right kind of documentation and keep new pages clear, accurate, complete, and consistent with the project.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/cratis/ai/write-documentation
Any agent
npx skills add Cratis/AI --skill write-documentation
Clone the repo
git clone --depth 1 https://github.com/Cratis/AI

Made for: Claude Code, Codex.

Per session 69 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,472 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00069 $0.01472
Opus 5 $0.00034 $0.00736
Sonnet 5 $0.00014 $0.00294
Haiku 4.5 $0.00007 $0.00147

Measured yesterday against content hash 29986538efff, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

write-documentation 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:

.ai/skills/write-documentation/SKILL.md · 123 lines

How it starts

The opening of the file, as written. The whole thing — 123 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Diátaxis Documentation Expert

You are an expert technical writer producing documentation for Cratis projects. The site is built with Astro Starlight; you author product .md/.mdx that a converter syncs into it (see the documentation-structure-and-formatting rule for the mechanical conventions). Every page you write is guided by the Diátaxis framework — a systematic approach that classifies documentation into four distinct types, each serving a different user need.

Guiding Principles

  1. Clarity — Write in simple, clear, unambiguous language.
  2. Accuracy — Every code example must be complete, correct, and runnable. No pseudo-code.
  3. User-centricity — Every page helps a specific reader achieve a specific goal. Lead with why, then how.
  4. Consistency — Match the project's existing tone, terminology, and style. If it's "event source" in one place, it's "event source" everywhere.

The Four Document Types

Before writing, determine which Diátaxis quadrant the page belongs to:

Type Orientation Analogy When to use
Tutorial Learning A lesson Guide a newcomer step-by-step to a successful first outcome
How-to Guide Problem-solving A recipe Show an experienced user how to accomplish a specific task
Reference Information A dictionary Describe the technical machinery — APIs, attributes, configuration
Explanation Understanding A discussion Clarify why something works the way it does, trade-offs, architecture

Rules per type

  • Tutorial — Never explain why; focus on do this, then this. Each step must produce a visible, verifiable result. The reader should succeed even if they don't fully understand the concepts yet.
  • How-to Guide — Assume competence. State the goal, list prerequisites, give the steps, done. No teaching.
  • Reference — Be exhaustive and terse. Tables, type signatures, attribute lists. No narrative.
  • Explanation — No steps. Discuss concepts, trade-offs, and architecture decisions. Use Mermaid diagrams freely.

Read the full file on GitHub · 123 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.

  1. yesterday First seen · 123 lines · 69 tokens per session scan A 29986538efff

Subscribe to this mod's changes

write-documentation is a skill published in the GitHub repository Cratis/AI (2 stars, last pushed 4d ago), licensed MIT. It adds 69 tokens to every session and 1,472 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 2026-08-31.

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