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 Kastalien-Research/thoughtbox --skill writing-clearly-and-conciselygit clone --depth 1 https://github.com/Kastalien-Research/thoughtboxWrote 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/kastalien-research/thoughtbox/writing-clearly-and-concisely)<a href="https://agentmods.dev/skills/kastalien-research/thoughtbox/writing-clearly-and-concisely"><img src="https://agentmods.dev/badge/skills/kastalien-research/thoughtbox/writing-clearly-and-concisely/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/kastalien-research/thoughtbox/writing-clearly-and-concisely"><img src="https://agentmods.dev/badge/skills/kastalien-research/thoughtbox/writing-clearly-and-concisely.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00047 | $0.00844 |
| Opus 5.5 | $0.00019 | $0.00338 |
| Sonnet 5.5 | $0.00009 | $0.00169 |
| Haiku 4.5 | $0.00005 | $0.00084 |
Grade A, and why
writing-clearly-and-concisely 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 1mo 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.
This is a copy
100% identical to writing-clearly-and-concisely — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Writing Clearly and Concisely
Overview
Write with clarity and force. This skill covers what to do (Strunk) and what not to do (AI patterns).
When to Use This Skill
Use this skill whenever you write prose for humans:
- Documentation, README files, technical explanations
- Commit messages, pull request descriptions
- Error messages, UI copy, help text, comments
- Reports, summaries, or any explanation
- Editing to improve clarity
If you're writing sentences for a human to read, use this skill.
Limited Context Strategy
When context is tight:
- Write your draft using judgment
- Dispatch a subagent with your draft and the relevant section file
- Have the subagent copyedit and return the revision
Loading a single section (~1,000-4,500 tokens) instead of everything saves significant context.
Elements of Style
William Strunk Jr.'s The Elements of Style (1918) teaches you to write clearly and cut ruthlessly.
Rules
Elementary Rules of Usage (Grammar/Punctuation):
- Form possessive singular by adding 's
- Use comma after each term in series except last
- Enclose parenthetic expressions between commas
- Comma before conjunction introducing co-ordinate clause
- Don't join independent clauses by comma
- Don't break sentences in two
- Participial phrase at beginning refers to grammatical subject
Elementary Principles of Composition:
- One paragraph per topic
- Begin paragraph with topic sentence
- Use active voice
- Put statements in positive form
- Use definite, specific, concrete language
- Omit needless words
- Avoid succession of loose sentences
- Express co-ordinate ideas in similar form
- Keep related words together
- Keep to one tense in summaries
- Place emphatic words at end of sentence
Reference Files
The rules above are summarized from Strunk's original text. For complete explanations with examples:
| Section | File | ~Tokens |
|---|---|---|
| Grammar, punctuation, comma rules | 02-elementary-rules-of-usage.md |
2,500 |
| Paragraph structure, active voice, concision | 03-elementary-principles-of-composition.md |
4,500 |
| Headings, quotations, formatting | 04-a-few-matters-of-form.md |
1,000 |
| Word choice, common errors | 05-words-and-expressions-commonly-misused.md |
4,000 |
What ships with it
6 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.
- elements-of-style/01-introductory.md 303 B
- elements-of-style/02-elementary-rules-of-usage.md 12 KB
- elements-of-style/03-elementary-principles-of-composition.md 33 KB
- elements-of-style/04-a-few-matters-of-form.md 4.8 KB
- elements-of-style/05-words-and-expressions-commonly-misused.md 22 KB
- signs-of-ai-writing.md 93 KB
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.
- 1mo ago First seen · 94 lines · 47 tokens per session scan A c5f4ecc8bfa7
writing-clearly-and-concisely is a skill published in the GitHub repository Kastalien-Research/thoughtbox (65 stars, last pushed 3mo ago), licensed MIT. It adds 47 tokens to every session and 844 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to writing-clearly-and-concisely, differing in 0 lines, and is treated as a copy.
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