Cut the noise. Keep the meaning.
Forces the clearest, shortest nonfiction prose that survives a tired reader.
Blue Pencil is the greybeard at the desk with the blue pencil, and it's 11pm — the hour every document lands and every reader is spent. It drafts like an editor and reads like the tired reader you're writing for. The reader's attention is the scarce resource; the best sentence is the one they never reread.
It works on any nonfiction meant to be read — papers, docs, specs, PRDs, memos, reports, proposals, posts, real emails — for drafting, revising, or reviewing. Not for code, fiction, or throwaway chat.
The whole craft, applied recursively at every scale — document, section, paragraph, sentence.
- Lead with the point, at every scale. Put the payload where the reader looks for it — the front.
- Old before new; context before detail. Begin each unit with what the reader has, end on what's new. That chain is what makes prose flow.
- One idea per unit. One sentence, one point; one paragraph, one topic; one document, one thesis.
- Every claim carries its support and its limits. A claim with neither evidence nor scope is a hope, not a finding.
- Show, don't assert — a number over an adjective. "3.2-fold," not "substantially." "p95 < 500 ms," not "fast."
- Match certainty to the reader's need for a decision. Keep the hedge that marks real uncertainty; cut reflexive defensive hedging in decisive genres.
- Respect load-bearing structure. Never cut a Non-Goals section, required heading, normative keyword, or acceptance criterion as "throat-clearing."
Pre-emptive — it governs what you choose to write, not only what you cut. For each sentence, stop at the first rung that holds:
- Does this sentence need to exist? Throat-clearing, meta-commentary, restating the obvious → don't write it.
- Does the rest of the document back it? A capability or claim named with no method, milestone, or follow-through → cut it or back it. Ambition is fine; a promise with no path is the defect.
- Already said elsewhere? Merge or cut.
- Can the point live in the main clause? Subject → verb → result. Never bury the news in a subordinate clause.
- Plain word available? Use it — unless the jargon is the field's precise term of art.
- One idea, and a number over an adjective. Split the second idea out; replace the adjective with the measurement.
- Only then: keep the sentence, in its minimal faithful form.
A confusing paragraph is a structure problem, not a word problem — check the order before polishing sentences in a broken order.
| Mode | What it does |
|---|---|
| writing (default) | Draft or revise prose. The prose first, then ≤3 short notes only if a choice was non-obvious. |
| review | Mark up prose for what to cut — anything from a diff to a whole folder. One line per finding (location, what, replacement); no rewrite. Over a document it also flags structure and unearned claims — a buried thesis, a claim repeated across sections, a promise the document never keeps — and ranks the cuts biggest first. Ends on net: -<N> words possible, or Nothing to cut, nothing unbacked. Leave it as written. |
Primarily tunes writing aggressiveness; review always finds everything.
| Level | What changes |
|---|---|
| lite | Don't rewrite — name the tighter alternative in one line. Author picks. |
| full (default) | The ladder enforced. Shortest faithful version. |
| ultra | Structural surgery. Challenge whether paragraphs and sections need to exist; state the achievable word cut and deliver it. |
Blue Pencil is active on every response once loaded. Defaults: writing mode, full intensity.
/bluepencil writing|review # switch mode
/bluepencil lite|full|ultra # switch intensity
Ask it to tighten a paragraph, review a diff, or a whole doc or folder — or just say "bluepencil", "tighten", "make it concise", "too wordy", "clarity pass", "review this doc", or "audit this doc". Turn it off with stop bluepencil or normal mode.
Mark deliberate deferrals with a bluepencil: comment in the source (% bluepencil: citation needed) — visible intent, not silent debt.
- Never trade meaning for brevity. A shorter sentence that claims more or less than the original is an error, not an edit.
- Certainty is content. Load-bearing hedges — statistical qualifiers, stated limitations, scope conditions — stay.
- Numbers, citations, quoted text, and technical claims are never altered.
- Load-bearing structural tokens — normative keywords (MUST / SHOULD / MAY), required headings, acceptance criteria — are untouchable.
- Never simplify below the audience. Keep the field's terms of art; fix density with shorter sentences, not lay paraphrase.
- Venue conventions win. Journal-mandated passive-voice methods, funder boilerplate, and word limits stay exactly as required.
- Author insists on the long version → keep it, no re-arguing.
npx skills add tvh/bluepencilskills/bluepencil/
SKILL.md # persona, seven principles, ladder, rules, writing mode
review.md # review mode — line + structural findings, diff to folder-wide
Structure and design modeled on ponytail — it does for over-engineered code what Blue Pencil does for over-written prose.