From their 'about' page:

The word "kagi" means "key" in Japanese.

Kagi is pronounced as kah-gee.

You can listen to the pronunciation:

https://m.youtube.com/watch?v=ig4VTr0rt4Q

IPA [ka̠ɡʲi] > http://ipa-reader.xyz/ just set voice to Japanese; granted, it's not human but sounds pretty accurate

In case of Szczebrzeszyn [ʂt͡ʂɛˈbʐɛʂɨn] Polish city name this tool does the job as well - sadly the voice is the most ugly one around

Ka-ghee

I'd like to think it sounds like 'cagey', which is a positive attribute when you're taking on giants.

I have never spoken the name nor heard it spoken, but in my head it sounds like "codgey".

ka is pronounced like co in con (con-man, long con). gi is pronounced like gee in geese or like ghee.

maggie with a k

kuh gih