{"name": "ctf42 API", "version": "1", "description": "Read-only, no key needed. Archive of past CTF challenges with handout files, writeup links, technique tags (e.g. tcache-poisoning, sql-injection) and technologies (e.g. glibc@2.35).", "stats": {"ctfs": 500, "techniques": 3752, "challenges": 21507}, "openapi": "https://ctf42.online/api/openapi.json", "llms_txt": "https://ctf42.online/llms.txt", "mcp": "https://ctf42.online/mcp", "rate_limit": "Fair use; bursts over ~120 requests/minute get HTTP 429.", "endpoints": {"challenges": "https://ctf42.online/api/challenges/", "challenge": "https://ctf42.online/api/challenges/{id}/", "similar": "https://ctf42.online/api/challenges/{id}/similar/", "ctfs": "https://ctf42.online/api/ctfs/", "ctf": "https://ctf42.online/api/ctfs/{slug}/", "techniques": "https://ctf42.online/api/techniques/", "technologies": "https://ctf42.online/api/technologies/"}, "categories": ["web", "pwn", "rev", "crypto", "forensics", "misc", "osint", "stego", "blockchain", "hardware", "mobile"], "difficulties": ["Beginner", "Easy", "Medium", "Hard", "Insane"], "sorts": ["complete", "newest", "oldest", "weight", "easiest", "hardest", "solves"]}