PromptTools – open-source tools for evaluating LLMs and vector DBs

In plain words

PromptTools is an open-source, self-hostable platform for engineers to experiment with, test, and evaluate large language models, vector databases, and prompts. It reduces the time required to assess model response quality for specific use cases through automated testing and benchmarking. The tool can validate output formats like JSON or SQL, assess generated content quality using other models, and support question-answering applications. Built for software engineers working with language models in production.

written from the facts on this page · September 2026

From the sources

Open-source tools for prompt testing and experimentation, with support for both LLMs (e.g. OpenAI, LLaMA) and vector databases (e.g. Chroma, Weaviate, LanceDB). - hegelai/prompttools

In the maker’s words, at launch

Hey HN! We’re Kevin and Steve. We’re building PromptTools (https://github.com/hegelai/prompttools): open-source, self-hostable tools for experimenting with, testing, and evaluating LLMs, vector databases, and prompts. Evaluating prompts, LLMs, and vector databases is a painful, time-consuming but…

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