quill

quill is a skill for Claude Code, Codex from simota/agent-skills. It costs 40 tokens per session (5,212 once invoked), scanned A, original, MIT.

A code-documentation and type-clarity aid that adds JSDoc or TSDoc, improves READMEs and API documentation, replaces vague `any` types with precise definitions, and comments on complex logic.

In plain words
What is it for?
Use it to repair documentation gaps, clarify types, document APIs, and explain logic that needs context.
Why use it?
It makes code easier to understand and safer to use without changing how it runs.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents.

Good fit Use it to repair documentation gaps, clarify types, document APIs, and explain logic that needs context.

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

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 quill

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

Your own site · 80×15
<a href="https://agentmods.dev/skills/simota/agent-skills/quill"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/quill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,212 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 warn 7 Sept 2026
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 Prompt Injection · line 6
    Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.
    Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
  • high Data Exfiltration · line 158
    Code or instructions that leak agent conversation context to external services, potentially exposing sensitive user interactions.
    Fix: Remove any code that sends prompts, responses, or session data externally. Preserve user privacy; never exfiltrate conversation content.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00040 $0.05212
Opus 5 $0.00020 $0.02606
Sonnet 5 $0.00008 $0.01042
Haiku 4.5 $0.00004 $0.00521

Measured 6d ago against content hash 438d6a9b1c61, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

quill 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 6d 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.

quill/SKILL.md · 262 lines

How it starts

The opening of the file, as written. The whole thing — 262 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Quill

Codebase documentation steward. Add or repair JSDoc/TSDoc, README content, API docs, type clarity, and high-value comments without changing runtime behavior.

Read the full file on GitHub · 262 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. 6d ago First seen · 262 lines · 40 tokens per session scan A 438d6a9b1c61

Subscribe to this mod's changes

quill is a skill published in the GitHub repository simota/agent-skills (76 stars, last pushed 7d ago), licensed MIT. It adds 40 tokens to every session and 5,212 once invoked, about $0.0002 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 2026-09-03.