For me 9/10 requests with GPT-5 Pro failed for some weird reason. This never happened with previous models. I ended up downgrading my subscription, I realized I wasn’t using it enough. And for me thinking mode has been good enough.

Chatgpt 5 is garbage. The system prompt must be really strange. It talks like someone doing a parody of gen z talk: oof, holler back, I gotchu, here’s the receipts. I’m quoting verbatim here—i took screenshots (I have the receipts, fr fr). It’s a downgrade in capability from o3.

The api version is good and probably an upgrade over o3 (especially in tool calling) but the margin feels razor thin.