Testing GPT-5.5 in early access: what we are seeing so far

Lovable tested GPT-5.5 in early access and reports it outperforms GPT-5.4 on complex tasks, with a 12.5% improvement on the hardest benchmark at the same cost, 23.1% fewer tool calls per request, and 9.9% higher likelihood of resolving blocking tasks.

The model is described as more cost-efficient and better at unblocking builders during stalled build sessions.