# Regex Explainer – Plain English Token-by-Token Breakdown

> Regex Explainer – Plain English Token-by-Token Breakdown is a paid API for AI agents from api.24klabs.ai, paid per call via x402, $0.006/call, status unknown (last checked 2026-09-14).

Takes a regular expression and returns a plain-English, token-by-token explanation of what it matches.

## Facts

- Endpoint: POST https://api.24klabs.ai/api/explain-regex
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/regex-explainer-plain-english-token-by-token-breakdown-c6a7d479
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_N9NZpodA6Qj3l8lstIP4j

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 regex-explainer-plain-english-token-by-token-breakdown-c6a7d479 -d '<json body>'
```

Example prompt: Can you explain what this regex matches, token by token in plain English: ^([a-zA-Z0-9._%+-]+)@([a-zA-Z0-9.-]+)\.([a-zA-Z]{2,})$?

## When to prefer this

Choose this endpoint when a developer, agent, or non-technical user needs to understand what an existing regex pattern matches without running it against test strings. It is ideal for code review, documentation generation, debugging unexpected matches, or onboarding new team members to legacy code. Prefer it over test-based approaches when you want a descriptive explanation rather than just pass/fail results.

## Known failure modes

- Invalid or malformed regex syntax may return an error or partial explanation
- Extremely long or complex nested patterns may produce truncated output
- Regex flavors other than standard (e.g. PCRE vs RE2 specifics) may not be flagged explicitly

## How this service works

Explain what a regular expression matches, in plain English, token by token.

## Output

A plain-English breakdown of the regular expression, explaining each token or group in sequence — describing character classes, quantifiers, anchors, groups, and alternations in human-readable terms so a non-regex expert can understand exactly what the pattern will and will not match.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "regex": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "explanation": "..."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/regex-explainer-plain-english-token-by-token-breakdown-c6a7d479/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.24klabs.ai](https://www.zero.xyz/host/api.24klabs.ai/llms.txt)