Building CostRouter — Route AI requests to the cheapest capable model automatically.

CostRouter is a proposed API gateway that automatically routes AI requests to the cheapest capable model based on complexity analysis, potentially saving 50-70% of LLM spend. It offers one-line integration by changing the OpenAI base_url and supports multiple models including Llama, Gemini Flash, GPT-5, and Claude. The creator is validating the idea before building, targeting startups and mid-market companies spending $2k-$10k/month on LLM APIs.