When latency and budget are fixed, GPT-5.4 mini and nano make sense as subagents, not downgraded flagships
OpenAI’s GPT-5.4 mini and nano matter less as standalone “small models” than as working parts inside a multi-model system. The practical change is architectural: instead of sending every step to a flagship model, developers can now route routine coding, classification, extraction, and tool-driven actions to faster, cheaper subagents while reserving full GPT-5.4 for planning and…