LLMTest

LLMTest is a tool for developers who are building AI features into their applications. It acts as an intelligent layer between your app and various large language models (LLMs). You connect your AI feature to LLMTest, and it handles the complex task of selecting the best model, optimizing your prompts for cost and quality, and managing failovers if an API goes down. The core idea is that you can ship a basic version of your feature, and LLMTest works to make it more efficient and reliable over time.

The tool operates in two main modes. During the 'Build Phase,' it helps you benchmark your prompts across 340+ different AI models before you launch, so you start with the best option. Once your feature is live with real users, the 'Scale Phase' (or Autopilot mode) takes over. It continuously monitors your traffic, automatically testing new models and rewritten prompts every week. It only applies changes that pass a strict set of safety gates, ensuring quality doesn't drop while reducing costs. Key features include automatic failover during API outages, detailed cost tracking per feature, and integration with popular IDEs like Cursor and Claude Code.

LLMTest is ideal for developers and engineering teams who are integrating AI capabilities like chatbots, content generators, or data processors. It saves significant engineering time that would otherwise be spent on manual model testing and prompt engineering. Real-world use cases include optimizing a multi-step SEO blog post generator by using cheaper models for simpler tasks, automatically recovering from malformed JSON responses, and seamlessly switching models during an API outage so end-users never experience downtime.