# Unicode Confusables Checker

> Unicode Confusables Checker is a paid API for AI agents from fastx402.tools, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-19).

Detects Unicode homoglyph/confusable characters in text that could be used for spoofing or phishing attacks

## Facts

- Endpoint: GET https://fastx402.tools/unicode-confusables?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/unicode-confusables-checker-8b84ae74
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hhsOobY_f1jhoKMh3j1Ke

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 unicode-confusables-checker-8b84ae74
```

Example prompt: Check this domain for Unicode spoofing — is 'pаypal.com' using any lookalike Cyrillic or other non-Latin characters that could fool someone into thinking it's legitimate?

## When to prefer this

Use this endpoint when you need to detect Unicode homoglyph or lookalike character attacks in domain names, URLs, usernames, or any text identifier where spoofing is a concern. It is particularly valuable for IDN homograph attack detection and phishing URL validation. Prefer this over general-purpose text analysis when the specific concern is Unicode-based visual deception rather than semantic content.

## Known failure modes

- Missing 'text' query parameter returns an error
- Empty string input may return no flagged characters with is_suspicious: false
- Very long strings may exceed processing limits
- Non-string input types will fail schema validation
- Payment failure via x402 returns HTTP 402 before processing

## How this service works

216 pay-per-call tools for AI agents, from $0.001 per request in USDC on Base or Solana with x402. No account, no API key.

## Output

Returns a JSON object with the original text, a normalized (ASCII-equivalent) version, a boolean is_suspicious flag, and an array of flagged_characters. Each flagged character includes its position in the string, the character itself, its Unicode codepoint, the script it belongs to (e.g. Cyrillic), and an array of ASCII characters it can be confused with.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "text"
     ],
     "properties": {
      "text": {
       "type": "string",
       "description": "Text to check for confusable characters"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "text": {
       "type": "string"
      },
      "normalized": {
       "type": "string"
      },
      "is_suspicious": {
       "type": "boolean"
      },
      "flagged_characters": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "script": {
          "type": "string"
         },
         "position": {
          "type": "integer"
         },
         "character": {
          "type": "string"
         },
         "codepoint": {
          "type": "string"
         },
         "confusables": {
          "type": "array",
          "items": {
           "type": "string"
          }
         }
        }
       }
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "text": "pаypal.com",
  "normalized": "paypal.com",
  "is_suspicious": true,
  "flagged_characters": [
   {
    "script": "Cyrillic",
    "position": 1,
    "character": "а",
    "codepoint": "U+0430",
    "confusables": [
     "a"
    ]
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/unicode-confusables-checker-8b84ae74/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fastx402.tools](https://www.zero.xyz/host/fastx402.tools/llms.txt)