A knife has many uses, from cutting wood to stabbing people. This tool is very much specialized in the stabbing (not necessarily people, as you said, you could stab a ballistic dummy to see the damage it does). Do you really a think a stab-only knife should be sold with no background checks, with no tracking of who buys it ?

> This tool could be used to teach people, e.g. in OSINT challenges, it could be used to gather information for a pentesting job, it can be used to teach people about best practices online etc

Or just... look yourself up. Like most of the people on this HN thread have done.

We could debate where they are but surely there are limits? I wouldn't want everyone to have access to things like Pegasus (https://citizenlab.ca/2022/10/new-pegasus-spyware-abuses-ide...). You could argue Pegasus could be used to hack a phone of a child predator to save a life, just as you could argue this tool could be used to educate. Maybe for you this username tool falls outside of yours, but it looks more like a switchblade than a butter knife to me.