I use it with the documentation of what I'm building.

Paste in the relevant section of the developer docs, ask it to write a function, or ask it to produce a valid API request, etc.

I suppose it's like a junior dev in a sense but it's very fast, can correct its own mistakes if you point them out, and has an internet worth of knowledge about various approaches and troubleshooting techniques.

I find most people who don't see value haven't actually used GPT-4 yet. Have you?