# Readability Syllable Counter

> Readability Syllable Counter is a paid API for AI agents from readability.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Counts syllables per word and in total across any given text string.

## Facts

- Endpoint: POST https://readability.openverbs.com/v1/syllables
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/readability-syllable-counter-e5c2f7f2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XI_ZQn7tj0w4IXZWMLZ0a

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability readability-syllable-counter-e5c2f7f2 -d '<json body>'
```

Example prompt: Can you count the syllables in every word of this sentence, and give me the total: 'The quick brown fox jumps over the lazy dog'?

## When to prefer this

Choose this endpoint when you specifically need syllable-level granularity — per-word and total — rather than a high-level readability grade. It is the right choice for poetry scansion, lyric writing, Flesch-Kincaid input preparation, or any task where raw syllable counts matter rather than a composite readability score.

## Known failure modes

- Empty or missing 'text' field returns a validation error
- Non-English or heavily mixed-language text may yield inaccurate syllable counts
- Extremely long text may hit payload size limits
- Payment failure via x402 protocol returns 402 status before processing

## How this service works

Count syllables per word and in total across the text.

## Output

Returns a per-word syllable count for every token in the input text, along with a total syllable count across the entire text, enabling precise linguistic and readability analysis.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "text"
     ],
     "properties": {
      "text": {
       "type": "string",
       "description": "Word or text to count syllables in."
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/readability-syllable-counter-e5c2f7f2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from readability.openverbs.com](https://www.zero.xyz/host/readability.openverbs.com/llms.txt)