tldx

tldx is a command-line tool for checking domain availability at scale. It uses RDAP—the modern successor to the ancient WHOIS protocol—which means it's actually fast and reliable instead of returning "who dis?" every five seconds. You can feed it thousands of domains, generate variations with prefix/suffix combinations, filter with regex, and export results in multiple formats. It also supports MCP, so if you're building AI tools that need domain data, tldx plays nice with that workflow.

This is a tool for domain flippers, security researchers, and anyone who's ever needed to check 10,000 domains in under a minute instead of doing it one by one through some ancient WHOIS interface that times out mid-query. Nobody's getting rich off CLI tools, but the right tool at the right time is worth more than a pitch deck. Sometimes you just need to ship something that works.