Match the AI model to the task type to cut costs without losing quality
A small experiment shows that routing tasks to different AI models based on whether the answer can be verified leads to better cost efficiency. The test covered 120 tasks across 3 models, inspired by a framework from AI researcher Andrej Karpathy.
The core idea comes from a framework proposed by Andrej Karpathy. It centers on a concept called verifiability: some tasks have a clear right or wrong answer — like math problems or code tests — while others are open-ended, like writing an essay or giving strategic advice. For verifiable tasks, you can use a cheaper model and simply retry if it gets it wrong. For non-verifiable tasks, you need a stronger model from the start because there's no easy way to catch a bad answer.
The experiment first classified each task into one of these two categories, then automatically sent it to the appropriate model. Across 120 sample tasks and 3 models, this routing approach was more cost-effective than always using the most powerful model. The practical takeaway for AI agent builders: assign each step of your pipeline to the cheapest model that can reliably handle it, and reserve expensive models only where judgment truly matters.
Key points
- Decide which AI model to use based on whether the task has a checkable right answer
- Easy-to-verify tasks (math, code, classification) → use a cheaper model; retry if wrong
- Open-ended tasks (writing, strategy) → use a stronger model from the start
- Small-scale test (120 tasks, 3 models) confirmed cost savings with this approach
- Useful for multi-step AI agents: assign each step to the most cost-efficient model that fits
Quick term guide
- AI models
- The core brain or underlying program that powers an artificial intelligence tool.
- AI model
- A program that can understand prompts and produce text, code, or answers.
- AI Mode
- A Google Search feature that uses AI to answer longer, more detailed questions.
- framework
- A ready-made structure or toolkit that helps developers build software faster.
- verifiability
- How easily you can check whether an AI's answer is correct or not.
- AI agent
- An AI program that can inspect information and suggest what to do next.
- pipeline
- An automated sequence of steps that processes or moves data without manual intervention.
- AI agents
- AI agents are AI tools that can carry out steps toward a goal, not just answer once.