# Services from dev-utils.x402tookit.com on Zero

> dev-utils.x402tookit.com serves 7 paid API services for AI agents, indexed by Zero. Each is callable per call with payment handled by Zero.

Canonical page: https://www.zero.xyz/host/dev-utils.x402tookit.com
Live health (JSON, refreshed every minute): https://www.zero.xyz/host/dev-utils.x402tookit.com/health.json

## Services

- [JWT Decode & Security Flag Checker](https://www.zero.xyz/c/jwt-decode-security-flag-checker-94c9f949/llms.txt): $0.02/call via x402. Decodes a JWT's header and payload without verifying the signature, and flags security issues like alg:none, expiry, not-before violations, and missing claims.
- [Pwned Password Check (k-Anonymity SHA-1)](https://www.zero.xyz/c/pwned-password-check-k-anonymity-sha-1-99e2f491/llms.txt): $0.02/call via x402. Checks whether a password has appeared in known data breaches using k-anonymity: you send only the first 5 hex chars of its SHA-1 hash, and the service returns a breach count and verdict.
- [ICS Calendar Event Generator](https://www.zero.xyz/c/ics-calendar-event-generator-6c6a2e6c/llms.txt): $0.02/call via x402. Builds a properly escaped and folded RFC 5545 .ics calendar event file from title, start, end, location, and description fields.
- [Certificate Transparency Lookup](https://www.zero.xyz/c/certificate-transparency-lookup-5f41d984/llms.txt): $0.02/call via x402. Retrieves Certificate Transparency log data for a domain, including recent certs, certificate issuers, and all subdomains observed via Cert Spotter.
- [User-Agent String Parser](https://www.zero.xyz/c/user-agent-string-parser-413d46d6/llms.txt): $0.02/call via x402. Parses a User-Agent string to extract browser, OS, device class (desktop/mobile/tablet/tv/bot), and bot detection flag.
- [Cron Next Runs Calculator](https://www.zero.xyz/c/cron-next-runs-calculator-d6600049/llms.txt): $0.02/call via x402. Computes the next N scheduled run times for a 5-field cron expression at a given UTC offset, applying the standard day-of-month/day-of-week OR rule
- [JavaScript Regex Tester](https://www.zero.xyz/c/javascript-regex-tester-76124a58/llms.txt): $0.02/call via x402. Runs a JavaScript regex pattern against text and returns all matches, capture groups, and character indexes, with catastrophic-backtracking protection.

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

- [Zero catalog index](https://www.zero.xyz/llms.txt)