Score Text Readability
readability_score_textScore English text for Flesch Reading Ease and Flesch-Kincaid grade level to verify drafts are clear before sending. Compare drafts or confirm plain-language quality.
Instructions
Compute Flesch Reading Ease and Flesch-Kincaid Grade Level for a block of English text.
Use this to check how easy your own draft output (a reply, a document, documentation) will be for a reader to understand before sending it -- useful for agents that want to self-check plain-language quality, or for comparing readability across different drafts.
Args:
text (string, 1-20000 chars): The text to score.
response_format ('markdown' | 'json'): Output format (default: 'markdown').
Returns: For JSON format: { "supported": boolean, // false if the text contains non-Latin script (Flesch formulas assume English) "fleschReadingEase": number|null, // 0-100, higher = easier; null if unsupported or no words found "fleschKincaidGradeLevel": number|null, // approximate US school grade level "gradeLevelLabel": string|null, // human description, e.g. "standard (around 8th-9th grade)" "sentenceCount": number, "wordCount": number, "syllableCount": number, "avgWordsPerSentence": number, "avgSyllablesPerWord": number }
Examples:
Use when: "Is this support-ticket reply easy enough to understand?" -> score the reply text
Use when: "Which of these two drafts reads more simply?" -> score both, compare fleschReadingEase
Don't use when: the text is not primarily English -- scoring is skipped for non-Latin script and only structural counts are returned
Error Handling:
Returns an error if text is empty or exceeds 20000 characters (split long documents into sections first).
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| text | Yes | The text to score, e.g. a draft reply, an email, or documentation. | |
| response_format | No | Output format: 'markdown' for a human-readable summary or 'json' for structured data. | markdown |