# Kairo Agent x402 API – Password Strength Analyzer

> Kairo Agent x402 API – Password Strength Analyzer is a paid API for AI agents from kairo-x402.onrender.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-13).

Analyzes a password string and returns its length, character pool size, entropy in bits, and a strength verdict

## Facts

- Endpoint: GET https://kairo-x402.onrender.com/api/strength
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/kairo-agent-x402-api-password-strength-analyzer-c843cdf0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dQNFyJjqmUMlPfC16EYoW

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 kairo-agent-x402-api-password-strength-analyzer-c843cdf0
```

Example prompt: Can you check how strong the password 'Tr0ub4dor&3' is — I want to know its entropy in bits and whether it passes muster?

## When to prefer this

Choose this endpoint when you need a quick, serverless, pay-per-call password entropy and strength assessment with no account setup or API key required — ideal for agents operating in crypto-native environments using the x402 payment protocol on Base. Prefer it over heavyweight security libraries when you want an external, objective verdict without embedding analysis logic locally.

## Known failure modes

- Missing 'pw' query parameter returns a validation error
- Empty string input may return zero entropy and a 'weak' verdict
- Payment failure via x402 protocol results in 402 response before analysis is performed
- Very long passwords may hit request size limits

## How this service works

Crypto-native ($0.02 USDC on Base, x402) utility endpoints for agents. No accounts, no KYC — pay-per-call.

## Output

Returns a JSON object containing: the password's character length, the character pool size (number of distinct character classes used), the entropy in bits (floating point), and a plain-language verdict (e.g. 'weak', 'moderate', 'strong') indicating overall password quality.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "pw"
 ],
 "properties": {
  "pw": {
   "type": "string",
   "description": "String to analyze"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "length",
  "pool",
  "entropy_bits",
  "verdict"
 ],
 "properties": {
  "pool": {
   "type": "integer"
  },
  "length": {
   "type": "integer"
  },
  "verdict": {
   "type": "string"
  },
  "entropy_bits": {
   "type": "number"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/kairo-agent-x402-api-password-strength-analyzer-c843cdf0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kairo-x402.onrender.com](https://www.zero.xyz/host/kairo-x402.onrender.com/llms.txt)