update-docs

update-docs is a skill for Claude Code, Codex from jakubsuplicki/codument. It costs 63 tokens per session (3,509 once invoked), scanned A, original, Apache-2.0.

A workflow for writing project documentation from source code. It explains how to document purpose, design choices, boundaries, and decisions in plain language.

In plain words
What is it for?
Use it to create missing documentation or update docs after code changes.
Why use it?
It helps documentation explain why the project works the way it does instead of merely repeating code details.

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/jakubsuplicki/codument/update-docs
Any agent
npx skills add jakubsuplicki/codument --skill update-docs
Clone the repo
git clone --depth 1 https://github.com/jakubsuplicki/codument

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 update-docs

README.md
[![agentmods](https://agentmods.dev/badge/skills/jakubsuplicki/codument/update-docs.svg)](https://agentmods.dev/skills/jakubsuplicki/codument/update-docs)
Your own site
<a href="https://agentmods.dev/skills/jakubsuplicki/codument/update-docs"><img src="https://agentmods.dev/badge/skills/jakubsuplicki/codument/update-docs.svg" alt="Measured on agentmods" height="20"></a>
Per session 63 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,509 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 $0.00063 $0.03509
Opus 5 $0.00032 $0.01754
Sonnet 5 $0.00013 $0.00702
Haiku 4.5 $0.00006 $0.00351

Measured 3d ago against content hash 55407cdc5259, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

update-docs 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 3d 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.

.agents/skills/update-docs/SKILL.md · 220 lines

How it starts

The opening of the file, as written. The whole thing — 220 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Documentation Workflow

How to Document

You are writing documentation that another developer will read to understand this project. Your goal is to explain why things exist and how they fit together — not to restate what the code already says.

What good documentation looks like

Follow the documentation standard (the doc-audience-layers concept) — these are its layers, and the test for every line is "would this survive a refactor that renamed every symbol and reordered every line?":

  • In plain terms: 2-3 sentences a reader takes in 10 seconds to know if this is relevant to them. No jargon.
  • Design approach: why it is shaped this way — the forces and the chosen-vs-rejected approach, at role level. No identifiers, counts, or call order; that is mechanism, it drifts, and the agent reads it live from the code.
  • Invariants & boundaries: what must always hold or is forbidden — the landmines a reader cannot see in the local code, and what the feature deliberately does NOT do. Link each invariant to the test that enforces it, or mark it "untested". This is consistently the most valuable section.
  • Decisions: pointers to the ADRs that hold the durable why. Reference, never restate.
  • Key files: each file's one-line narrative role (orchestrator / analyzer / seam) — not its exports. The registry holds the exact file list.

What bad documentation looks like — do NOT write this

  • Restating function names as descriptions ("readRegistry reads the registry")
  • Listing exports without explaining what they're for
  • Copy-pasting large code blocks instead of referencing file paths
  • Revision history, glossaries, or timeline sections
  • Vague descriptions ("handles X logic for the application")

Start from codument doctor

Before writing anything, find out what actually needs work — don't guess. codument doctor is the deterministic gap list; let its findings (warnings) drive the pass, and re-run it after each fix so you can watch the finding clear. A finding that re-runs clean is the done signal — there is no separate sign-off.

Read the full file on GitHub · 220 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. 3d ago First seen · 220 lines · 63 tokens per session scan A 55407cdc5259

Subscribe to this mod's changes

update-docs is a skill published in the GitHub repository jakubsuplicki/codument (47 stars, last pushed 13d ago), licensed Apache-2.0. It adds 63 tokens to every session and 3,509 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.