Route your prompts to the best LLM
Hey HN, we've just finished building a dynamic router for LLMs, which takes each prompt and sends it to the most appropriate model and provider. We'd love to know what you think! Here is a quick(ish) screen-recroding explaining how it works: https://youtu.be/ZpY6SIkBosE Best results when training a custom router on your own prompt data: https://youtu.be/9JYqNbIEac0 The router balances user preferences for quality, speed and cost. The end result is higher quality and faster LLM responses at lower cost. The quality for each candidate LLM is predicted ahead of time…
In plain words
This product is a dynamic router that automatically directs each user prompt to the most suitable large language model from available providers. It uses a neural scoring function to predict which model will deliver the best results for each prompt, while balancing trade-offs between quality, speed, and cost. The router can be customized by training on a user's own prompt data, and it processes multiple LLMs across batches to optimize response quality and performance at lower cost. It is designed for developers and organizations that want to maximize efficiency when using multiple LLM services.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
Hey HN, we've just finished building a dynamic router for LLMs, which takes each prompt and sends it to the most appropriate model and provider. We'd love to know what you think! Here is a quick(ish) screen-recroding explaining how it works: https://youtu.be/ZpY6SIkBosE Best results when training a custom router on your own prompt data: https://youtu.be/9JYqNbIEac0 The router balances user preferences for quality, speed and cost. The end result is higher quality and faster LLM responses at lower cost. The quality for each candidate LLM is predicted ahead of time using a neural scoring function, which is a BERT-like architecture conditioned on the prompt and a latent representation of the LLM being scored. The different LLMs are queried across the batch dimension, with the neural scoring architecture taking a single latent representation of the LLM as input per forward pass. This makes the scoring function very modular to query for different LLM combinations. It is trained in a supervised manner on several open LLM datasets, using GPT4 as a judge. The cost and speed data is taken from our live benchmarks, updated every few hours across all continents. The final "loss function" is a linear combination of quality, cost, inter-token-latency and time-to-first-token, with the user effectively scaling the weighting factors of this linear combination. Smaller LLMs are often good enough for simple prompts, but knowing exactly how and when they might break is difficult. Simple perturbations of the phrasing can cause smaller LLMs to fail catastrophically, making them hard to rely on. For example, Gemma-7B converts numbers to strings and returns the "largest" string when asking for the "largest" number in a set, but works fine when asking for the "highest" or "maximum". The router is able to learn these quirky distributions, and ensure that the smaller, cheaper and faster LLMs are only used when there is high confidence that they will get the answer correct. Pricing-wise, we charge the same rates as the backend providers we route to, without taking any margins. We also give $50 in free credits to all new signups. The router can be used off-the-shelf, or it can be trained directly on your own data for improved performance. What do people think? Could this be useful? Feedback of all kinds is welcome!
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