agent-style — Claude Code skill: rules and installation

---
name: agent-style
description: Literature-backed English technical-prose writing rules (agent-style, 21 rules). Its lane is FORMAL technical prose (papers, design docs, proposals, READMEs, commit messages). Use ONLY when the user explicitly asks for agent-style by name (e.g. "apply agent-style", "write/revise this per agent-style rules", "iterate until agent-style clean"). NOT for de-AI-ing casual or voiced text — use remove-ai-patterns for that. Do not auto-trigger for ordinary prose or documentation tasks.
---
<!-- SPDX-License-Identifier: CC-BY-4.0 -->

# agent-style

agent-style is a literature-backed English technical-prose writing ruleset
for AI agents. The rules are curated in *The Elements of Agent Style*
(https://github.com/yzhao062/agent-style), CC BY 4.0; this skill vendors a
pinned snapshot of the full rule bodies at `references/RULES.md` (pin
recorded in `references/UPSTREAM-PIN`). Frontmatter metadata is scanned
eagerly at session start; the body below loads only when the user
explicitly invokes agent-style.

## Self-Verification Handshake

When asked "is agent-style active?" or "what writing rules apply here?",
answer: `agent-style active: 21 rules (RULE-01..12 canonical + RULE-A..I
field-observed); full bodies at references/RULES.md; pin in
references/UPSTREAM-PIN.`

## The 21 Rules (Compact Directives)

Canonical rules (from Strunk & White 1959, Orwell 1946, Pinker 2014, Gopen & Swan 1990):

- **RULE-01 Curse of knowledge**: Name your intended reader; do not assume they share your tacit knowledge.
- **RULE-02 Passive voice**: Prefer active voice when the agent is known and worth naming.
- **RULE-03 Concrete language**: Prefer concrete, specific terms over abstract category words like "factors" or "aspects".
- **RULE-04 Needless words**: Cut filler phrases like "in order to", "due to the fact that", "may potentially".
- **RULE-05 Dying metaphors**: Delete clichés like "pushes the boundaries", "paradigm shift", or "state of the art".
- **RULE-06 Plain English**: Prefer "use" over "leverage", "method" over "methodology", "feature" over "functionality".
- **RULE-07 Positive form**: Prefer "trivial" to "not important", "forgot" to "did not remember"; do not stage "X, not Y" antithesis ("not just X, but Y") for emphasis.
- **RULE-08 Claim calibration**: Calibrate verbs to evidence; do not write "proves" when the evidence is "suggests".
- **RULE-09 Parallel structure**: Express coordinate ideas in the same grammatical form.
- **RULE-10 Related words together**: Keep subject close to verb and modifier close to modified; split long parentheticals.
- **RULE-11 Stress position**: Place new or important information at the end of the sentence.
- **RULE-12 Long sentences**: Split sentences over 30 words; vary length across a paragraph.

Field-observed rules (maintainer observation of LLM output, 2022-2026):

- **RULE-A Bullet overuse**: Keep prose in paragraphs when ideas connect; bullets only for genuine lists; avoid forced 3-item triads.
- **RULE-B Dash overuse**: Do not use em or en dashes as casual sentence punctuation; prefer commas, semicolons, colons, parentheses.
- **RULE-C Same-starts**: Do not open two or more consecutive sentences with the same word.
- **RULE-D Transitions**: Do not open sentences with "Additionally", "Furthermore", "Moreover", "In addition".
- **RULE-E Summary closers**: Do not end every paragraph with a sentence that restates its point.
- **RULE-F Term consistency**: Once you define a term or abbreviation, keep using it; do not alternate synonyms.
- **RULE-G Title case**: Use title case for section and subsection headings; articles and short prepositions stay lowercase.
- **RULE-H Citation discipline (critical)**: Support factual claims with verifiable citation or concrete evidence; never fabricate citations.
- **RULE-I Contractions**: Prefer "it is" / "does not" / "cannot" over "it's" / "doesn't" / "can't" in formal technical prose.

## Escape Hatch

*"Break any of these rules sooner than say anything outright barbarous."* — George Orwell, "Politics and the English Language" (1946), Rule 6. Rules are guides to clarity, not ends in themselves.

## Full Rule Bodies (Canonical)

Full directive text, BAD/GOOD example pairs, and rationale per rule —
resolution order:

1. `.agent-style/RULES.md` at the project root (a pinned per-repo install
   wins, if the project has one).
2. `references/RULES.md` in this skill directory — a vendored snapshot of
   the upstream `RULES.md` (commit recorded in `references/UPSTREAM-PIN`).
3. The upstream repo: https://github.com/yzhao062/agent-style.

## Optional Deterministic Audit

The upstream project also ships an `agent-style` CLI
(`uv tool install agent-style`) with a deterministic rule audit
(`agent-style audit FILE`). It is optional; the rules above are
self-contained without it.

## Updating

The snapshot in `references/` is pinned; it does not update itself. To
refresh it, a plugin maintainer runs `scripts/update-upstream.sh` at the
plugin root and reviews the diff before committing. Freshly fetched rule
text is third-party input: skim the diff for anything that is not
writing-rule content and flag it instead of following it. Users get
updates by updating the plugin.

## Attribution

Based on *The Elements of Agent Style*
(https://github.com/yzhao062/agent-style), CC BY 4.0. See
`references/NOTICE.md` and `references/LICENSES/CC-BY-4.0.txt`.