How do I install the Flesch Kincaid Proofreader skill?

Run npx skillmds@latest add therapys/flesch-kincaid-proofreader in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Flesch Kincaid Proofreader safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Flesch Kincaid Proofreader?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Flesch Kincaid Proofreader free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Flesch Kincaid Proofreader?

therapys (@therapys) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Flesch Kincaid Proofreader by therapys

Name: Flesch Kincaid Proofreader
Author: therapys

Flesch Kincaid Proofreader

Measure and improve the readability of English copy with the Flesch–Kincaid grade-level test. Use when proofreading or simplifying READMEs, documentation, product copy, help text, announcements, or other prose, especially when a target reading grade is requested.

therapys Updated Sep 21, 2026

File contents

Flesch–Kincaid Proofreader

Use the bundled script for measurement and sentence triage. Use the language model only for the semantic work a deterministic tool cannot do: preserving meaning, voice, and technical accuracy while rewriting.

Workflow

Choose the target grade. Use the user's target when given; otherwise grade 8.

Run the analyzer before editing:

node scripts/readability.mjs --target 8 path/to/README.md

Review difficult sentences in descending grade order. Start with sentences that are both long and far above target. Listed complex words are candidates, not automatic errors.
Rewrite only where useful. Prefer:
- one main idea per sentence;
- familiar, precise words over longer synonyms;
- active, concrete constructions;
- bullets for genuine lists;
- keeping required technical terms and explaining them once.
Re-run the same command. Continue until the copy meets the target or further simplification would harm accuracy, voice, or usefulness.
Report the before/after grade and any intentional exceptions. Never claim a passing score proves the copy is clear or correct.

Do not estimate the grade yourself, count words or syllables manually, or ask the model to rank every sentence. The script owns those deterministic steps.

Commands

Analyze one or more files:

node scripts/readability.mjs --target 8 README.md docs/getting-started.md

Analyze selected text through stdin:

printf '%s\n' 'Paste the copy here.' | node scripts/readability.mjs --target 8

Produce structured output for another tool:

node scripts/readability.mjs --json --target 8 README.md

Use as a check that exits with status 1 when any document is above target (or has no prose):

node scripts/readability.mjs --target 8 --fail-above README.md

Run node scripts/readability.mjs --help for all options. Markdown code blocks, link destinations, HTML tags, comments, headings, tables, and frontmatter are excluded by default. Inline code remains because it is often part of a technical sentence. Pass --include-code only when fenced code blocks should count as prose.

Interpretation

The script implements:

0.39 × (words / sentences) + 11.8 × (syllables / words) − 15.59

A result of 8.0 roughly indicates text suited to a US eighth-grade reader. Negative values are valid for very simple text. The test measures sentence length and estimated word length; it does not measure correctness, structure, jargon familiarity, accessibility, tone, or reader knowledge.

Syllable counting is a deterministic English heuristic, so names, acronyms, code identifiers, and specialist terms may be miscounted. Treat small score differences as noise. Keep accurate terms rather than gaming the score, and use judgment for text that is not English.

Validation

After changing the analyzer, run:

node --test tests/*.test.mjs

---name: flesch-kincaid-proofreaderdescription: Measure and improve the readability of English copy with the Flesch–Kincaid grade-level test. Use when proofreading or simplifying READMEs, documentation, product copy, help text, announcements, or other prose, especially when a target reading grade is requested.---# Flesch–Kincaid ProofreaderUse the bundled script for measurement and sentence triage. Use the language model only for the semantic work a deterministic tool cannot do: preserving meaning, voice, and technical accuracy while rewriting.## Workflow1. Choose the target grade. Use the user's target when given; otherwise grade 8.2. Run the analyzer before editing: ```bash node scripts/readability.mjs --target 8 path/to/README.md ```3. Review difficult sentences in descending grade order. Start with sentences that are both long and far above target. Listed complex words are candidates, not automatic errors.4. Rewrite only where useful. Prefer: - one main idea per sentence; - familiar, precise words over longer synonyms; - active, concrete constructions; - bullets for genuine lists; - keeping required technical terms and explaining them once.5. Re-run the same command. Continue until the copy meets the target or further simplification would harm accuracy, voice, or usefulness.6. Report the before/after grade and any intentional exceptions. Never claim a passing score proves the copy is clear or correct.Do not estimate the grade yourself, count words or syllables manually, or ask the model to rank every sentence. The script owns those deterministic steps.## CommandsAnalyze one or more files:```bashnode scripts/readability.mjs --target 8 README.md docs/getting-started.md```Analyze selected text through stdin:```bashprintf '%s\n' 'Paste the copy here.' | node scripts/readability.mjs --target 8```Produce structured output for another tool:```bashnode scripts/readability.mjs --json --target 8 README.md```Use as a check that exits with status 1 when any document is above target (or has no prose):```bashnode scripts/readability.mjs --target 8 --fail-above README.md```Run `node scripts/readability.mjs --help` for all options. Markdown code blocks, link destinations, HTML tags, comments, headings, tables, and frontmatter are excluded by default. Inline code remains because it is often part of a technical sentence. Pass `--include-code` only when fenced code blocks should count as prose.## InterpretationThe script implements:```text0.39 × (words / sentences) + 11.8 × (syllables / words) − 15.59```A result of `8.0` roughly indicates text suited to a US eighth-grade reader. Negative values are valid for very simple text. The test measures sentence length and estimated word length; it does **not** measure correctness, structure, jargon familiarity, accessibility, tone, or reader knowledge.Syllable counting is a deterministic English heuristic, so names, acronyms, code identifiers, and specialist terms may be miscounted. Treat small score differences as noise. Keep accurate terms rather than gaming the score, and use judgment for text that is not English.## ValidationAfter changing the analyzer, run:```bashnode --test tests/*.test.mjs```

Frequently asked questions