GPT5 is worse than 4.1-mini for text and worse than Sonnet 4 for coding
It seems that OpenAI have got the PR machine working amazingly. The Cursor CEO said it's the best, as did Simon Willison (https://simonwillison.net/2025/Aug/7/gpt-5/).But I've found it terrible. For coding (in Cursor), it's slow, fails with tool calls often (no MCP just stock Cursor tools) and stored some new application state in globalThis - something that no model has ever attempted to do in...