Readability Analyzer

Overview

Computes readability scores using configurable formulas. Language scope differs per formula: Flesch Reading Ease and Flesch-Kincaid Grade are syllable-based and calibrated for ENGLISH only (syllable estimation uses an English heuristic requiring explicit opt-in); Automated Readability Index and Coleman-Liau are character/word-based and less English-specific but still calibrated on English corpora. Scores are indices, not verified reading levels. Accepts file input via file_ref — no need to extract file content first.

Readability scores depend on exact word, sentence, and syllable counts — we apply published formulas so your numbers are defensible, not estimated.

When to use it

Scope

Non-goals

• Does not provide reading level labels or grade-band classifications
• Does not support non-English syllable counting natively
• Does not assess writing quality, clarity, or style

Properties

Capabilities

Cost & billing

Flat rate per invocation

File handling

File limits

Constraints this skill applies to your input and generated files. The “Limited by” column shows the static source of each cap; none of these can be raised by upgrading your plan.

How we handle your data

Input schema

Output schema

API contract

curl -sS -X POST "$BASE/v1/execute" -H "Authorization: Bearer $KEY" -H 'Content-Type: application/json' -d '{"skillKey":"text.measure_readability","input":{"text":"The quick brown fox jumps over the lazy dog.","allow_heuristic_syllables":true}}'

import { Squillify } from "@squillify/sdk";

const sq = new Squillify({ apiKey: process.env.SQUILLIFY_API_KEY });

const { output } = await sq.execute("text.measure_readability", {"text":"Kubernetes orchestrates containerized applications across clusters of machines. It automates deployment, scaling, and management of containerized workloads and services.","formulas":["flesch_reading_ease"],"allow_heuristic_syllables":true,"return_details":false});

Errors

Other limits

Limitations

• Does not provide reading level labels or grade-band classifications
• Does not support non-English syllable counting natively
• Does not assess writing quality, clarity, or style
• Non-English readability (syllable heuristic is English-only)
• Literary or stylistic analysis
• Writing quality assessment (use a human reviewer)

How to call

POST /v1/execute (requires authentication)

{
  "skillKey": "text.measure_readability",
  "input": {
    "text": "Kubernetes orchestrates containerized applications across clusters of machines. It automates deployment, scaling, and management of containerized workloads and services.",
    "formulas": [
      "flesch_reading_ease"
    ],
    "allow_heuristic_syllables": true,
    "return_details": false
  }
}

Examples

{
  "text": "Kubernetes orchestrates containerized applications across clusters of machines. It automates deployment, scaling, and management of containerized workloads and services.",
  "formulas": [
    "flesch_reading_ease"
  ],
  "allow_heuristic_syllables": true,
  "return_details": false
}

{
  "skill": "text.measure_readability",
  "policy": "formula_based",
  "formulas": [
    {
      "name": "flesch_reading_ease",
      "score": -34.3,
      "reliability": "BEST_EFFORT"
    }
  ],
  "locale": "en-US",
  "warnings": [
    "Syllable count is estimated heuristically for locale en-US. Readability score is approximate."
  ],
  "unit": "readability_score"
}

{
  "text": "The sun rose over the hills. Birds sang in the trees. A gentle breeze blew through the open window.",
  "formulas": [
    "flesch_reading_ease"
  ],
  "allow_heuristic_syllables": true,
  "return_details": false
}

{
  "skill": "text.measure_readability",
  "policy": "formula_based",
  "formulas": [
    {
      "name": "flesch_reading_ease",
      "score": 93.5,
      "reliability": "BEST_EFFORT"
    }
  ],
  "locale": "en-US",
  "warnings": [
    "Syllable count is estimated heuristically for locale en-US. Readability score is approximate."
  ],
  "unit": "readability_score"
}

{
  "return_details": false,
  "formulas": [
    "coleman_liau_index"
  ],
  "file_ref": "squillify://files/f-9c2b41ea"
}

{
  "skill": "text.measure_readability",
  "policy": "formula_based",
  "formulas": [
    {
      "name": "coleman_liau_index",
      "score": 11.4,
      "reliability": "VERIFIABLE"
    }
  ],
  "locale": "en-US",
  "warnings": [],
  "unit": "readability_score"
}

Recommended use cases

• Content complexity assessment for editorial workflows
• Grade-level targeting for educational content
• Accessibility compliance checking
• Pre-publish readability gating in content pipelines

Avoid for

• Non-English readability (syllable heuristic is English-only)
• Literary or stylistic analysis
• Writing quality assessment (use a human reviewer)

Related skills

Composable with

Safety & privacy

• Runs without calling any external service.
• Your payloads are never stored permanently.
• Telemetry captures metadata only — never your payload contents.
• We never train models on your payloads.
• No human reviews your payloads.

Tags