OpenAI says old prompts are holding GPT-5.5 back and developers need a fresh baseline

OpenAI published a GPT-5.5 prompting guide for developers.

It advises not to reuse legacy prompts and to start with the smallest effective prompt.

The guide recommends tuning reasoning effort and output requirements with examples.

Prompts should be structured around role, personality, goals, constraints, output, and stop rules.

The shift suggests older prompt patterns may underperform in GPT-5.5 production workflows.