I only learned about Native Messaging this week.
I've been hacking away at a browser-based tool that uses anthropic APIs on the backend. But what I really want is for the browser to talk to my local claude becuase I have MCPs, skills, network access for a bunch of things.
I started with a little proxy installed on my computer that the browser can call but knew it would never pass any security review. The alternative I didn't originally know about was Native Messaging.
It's a fairly benign way to let a browser talk to and execute commands on your computer. But doing it without disclosing is, I agree, very bad.
(tool I'm hacking away at needs to talk to local claude and acli: https://withlattice.com)