Technical Writing Readability API API ID: 12903

Streamline complex information using the Technical Writing Technical Writing Readability API for clear communication.
Use this API from your AI agent via MCP
Works with OpenClaw, Claude Code/Desktop, Cursor, Windsurf, Cline and any MCP-compatible AI client.
Docs & setup
Create a skill by wrapping this MCP: https://mcp.zylalabs.com/mcp?apikey=YOUR_ZYLA_API_KEY

## What it does
Score the readability of any English text or URL. Returns 5 industry-standard readability scores, actionable plain-English suggestions, sentence-level breakdown with the hardest sentences flagged, and optional target grade pass/fail.

## Scores returned
- **Flesch Reading Ease** — 0–100. Higher = easier to read.
- **Flesch-Kincaid Grade** — US school grade equivalent.
- **Gunning Fog Index** — Years of education needed to understand.
- **Automated Readability Index (ARI)** — Grade level via character/word ratio.
- **SMOG Index** — Grade level via polysyllabic word density.

## Use cases
Content teams, legal/compliance, EdTech, SEO tools, CMS pipelines, A/B copy testing.

## Endpoints
- `POST /api/analyze` — analyse text or a URL, with optional target grade
- `POST /api/compare` — compare two texts side by side

API Documentation

Endpoints


Analiza texto o una URL Devuelve 5 puntuaciones de legibilidad sugerencias desglose de oraciones y resultado de grado objetivo opcional



                                                                            
POST https://zylalabs.com/api/12903/technical+writing+readability+api/25683/analizar
                                                                            
                                                                        

analizar - Endpoint Features

Object Description
Request Body [Required] Json

Free test requests remaining: 3 of 3.


INPUT PARAMETERS


API EXAMPLE RESPONSE

{"success":true,"textStats":{"wordCount":18,"sentenceCount":2,"characterCount":85,"avgSentenceLength":9,"avgSyllablesPerWord":1.56,"polysyllabicWordCount":1,"polysyllabicWordPercentage":5.6},"scores":{"fleschReadingEase":{"score":66.1,"interpretation":"Standard","suitableFor":"Age 15–17"},"fleschKincaidGrade":{"score":6.3,"interpretation":"US Grade 6 reading level"},"gunningFog":{"score":5.8,"interpretation":"Very easy"},"automatedReadabilityIndex":{"score":5.3,"interpretation":"Roughly Grade 5 reading level"},"smogIndex":{"score":6.9,"interpretation":"Grade 7 reading level","note":"SMOG is most accurate with 30+ sentences"}},"overall":{"averageGradeLevel":6.1,"verdict":"Easy read","recommendedFor":"Most adults","plainEnglishScore":70},"suggestions":["Text is short (18 words). Readability scores are most reliable with 100+ words."],"sentenceBreakdown":{"all":[{"index":1,"sentence":"The quick brown fox jumps over the lazy dog.","wordCount":9,"fre":94.3,"grade":2.3,"complexity":"Easy"},{"index":2,"sentence":"This is a simple sentence for testing readability scores.","wordCount":9,"fre":37.9,"grade":10.2,"complexity":"Hard"}],"hardest":[{"index":2,"sentence":"This is a simple sentence for testing readability scores.","wordCount":9,"fre":37.9,"grade":10.2,"complexity":"Hard"},{"index":1,"sentence":"The quick brown fox jumps over the lazy dog.","wordCount":9,"fre":94.3,"grade":2.3,"complexity":"Easy"}]}}

Analizar - CODE SNIPPETS


curl --location --request POST 'https://zylalabs.com/api/12903/technical+writing+readability+api/25683/analizar' --header 'Authorization: Bearer YOUR_API_KEY' 

--data-raw '{"text": "The quick brown fox jumps over the lazy dog. This is a simple sentence for testing readability scores."}'

    

Compara la legibilidad de dos textos uno al lado del otro Devuelve puntuaciones de Flesch niveles de grado veredictos y un resumen de cuál texto es más fácil de leer



                                                                            
POST https://zylalabs.com/api/12903/technical+writing+readability+api/25684/comparar
                                                                            
                                                                        

comparar - Endpoint Features

Object Description
Request Body [Required] Json

Free test requests remaining: 3 of 3.


INPUT PARAMETERS


API EXAMPLE RESPONSE

{"success":true,"text_a":{"fleschReadingEase":100,"gradeLevel":2.1,"verdict":"Very easy read","wordCount":11},"text_b":{"fleschReadingEase":0,"gradeLevel":19.4,"verdict":"Highly technical","wordCount":15},"comparison":{"moreReadable":"text_a","easeDifference":100,"gradeDifference":17.3,"summary":"text_a is easier to read by 100.0 Flesch points"}}

Comparar - CODE SNIPPETS


curl --location --request POST 'https://zylalabs.com/api/12903/technical+writing+readability+api/25684/comparar' --header 'Authorization: Bearer YOUR_API_KEY' 

--data-raw '{"text_a": "The cat sat on the mat. It was a sunny day.", "text_b": "The feline proceeded to position itself upon the horizontal surface whilst meteorological conditions remained favourable."}'

    

API Access Key & Authentication

After signing up, every developer is assigned a personal API access key, a unique combination of letters and digits provided to access to our API endpoint. To authenticate with the Technical Writing Readability API simply include your bearer token in the Authorization header.
Headers
Header Description
Authorization [Required] Should be Bearer access_key. See "Your API Access Key" above when you are subscribed.

Simple Transparent Pricing

No long-term commitment. Upgrade, downgrade, or cancel anytime. Free Trial includes up to 50 requests.

🚀 Enterprise

Starts at
$ 10,000/Year


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  • ✔︎ Postman Integration
  • ✔︎ Secure HTTPS Connections
  • ✔︎ Reliable Uptime

Technical Writing Readability API FAQs

The `POST /api/analyze` endpoint returns readability scores, suggestions for improvement, a sentence breakdown, and an optional target grade result. The `POST /api/compare` endpoint provides a side-by-side comparison of two texts, including their readability scores, grade levels, and a summary of which text is easier to read.

Key fields include `success`, `textStats` (word, sentence, and character counts), `scores` (various readability metrics), `overall` (average grade level and verdict), `suggestions`, and `sentenceBreakdown` for detailed analysis.

The `POST /api/analyze` endpoint accepts parameters for the text or URL to analyze and an optional target grade for evaluation. The `POST /api/compare` endpoint requires two texts for comparison. Users can customize requests by providing different texts or URLs.

The response data is structured in JSON format, with top-level keys indicating success status, followed by nested objects for text statistics, readability scores, overall assessment, suggestions, and sentence breakdowns, making it easy to parse and utilize.

Typical use cases include content creation for clarity, legal document simplification, educational material assessment, SEO optimization, and A/B testing for marketing copy, helping teams ensure their communication is effective and accessible.

Users can leverage readability scores to identify complex sentences and improve text clarity. Suggestions can guide revisions, while sentence breakdowns help pinpoint specific areas needing simplification, enhancing overall communication quality.

The API employs established readability formulas, ensuring consistent and reliable scoring. Regular updates and testing against a variety of text samples help maintain accuracy and relevance in the readability assessments provided.

Users can expect a range of readability scores from 0 to 100, with higher scores indicating easier readability. The average grade level typically falls between 1 and 12, reflecting the educational level required to understand the text, allowing for quick assessments of text complexity.

General FAQs

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