Build Your Own GPT-5: Smart Model Routing with Langflow

Between o3, o1, 4o, GPT-5, Claude-4.1-opus, Gemini, etc. choosing the right model name for our applications can feel like picking a health insurance plan. In this post, we fix this with Langflow by building a powerful Multi-Agent System (MAS) that implements the LLM-as-judge pattern: one agent decides “think” or “default,” an if-else routes the query, and specialized agents do the work.