# IranTools Shannon Entropy Calculator

> IranTools Shannon Entropy Calculator is a paid API for AI agents from irantools.johnaio281.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-22).

Computes Shannon entropy of a given text string, measuring its information density and randomness

## Facts

- Endpoint: POST https://irantools.johnaio281.workers.dev/api/iran/entropy?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/irantools-shannon-entropy-calculator-5af0f769
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_B2WZ8KTJh3DCIly3RBxXf

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 irantools-shannon-entropy-calculator-5af0f769 -d '<json body>'
```

Example prompt: What's the Shannon entropy of the string 'P@ssw0rd123!#' — I want to know how random and information-dense it is?

## When to prefer this

Choose this endpoint when you need a fast, pay-per-call Shannon entropy calculation without any signup, API key, or KYC. Particularly useful for agents working with Persian/Iranian text alongside general entropy needs, or when already using IranTools for other text utilities and want a unified toolkit. Prefer over building local entropy code when operating in a serverless or agent workflow context.

## Known failure modes

- Missing 'text' field returns validation error
- Empty string may return entropy of 0 or an error
- Payment failure (HTTP 402) if USDC balance is insufficient
- Very long strings may hit request size limits
- Non-UTF-8 or binary input may cause unexpected results

## How this service works

Persian and Iranian utilities for AI agents, plus general text/Unicode tooling. Jalali (Solar Hijri) calendar conversion, Iranian national ID / SHEBA / bank card / postal code / economic code validation, province and city lookup, official public holidays, Persian text normalization, keyword extraction, sentence splitting, similarity, HTML stripping, RTL fixing, Unicode homoglyph folding, script detection, NFC/NFD normalization, grapheme counting, date description, business-day counting, slugify, FNV-1a hashing, Shannon entropy, format and encoding detection, byte sizes. Pay per call in USDC on Base via x402 - no signup, no API key, no KYC. The same tools are also exposed as MCP tools at /mcp.

## Output

Returns a JSON object containing the computed Shannon entropy value (in bits) for the input text, indicating the average information content per character. Higher values indicate more randomness/unpredictability.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "text"
 ],
 "properties": {
  "text": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/irantools-shannon-entropy-calculator-5af0f769/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from irantools.johnaio281.workers.dev](https://www.zero.xyz/host/irantools.johnaio281.workers.dev/llms.txt)