Experiment ▴ LLM UI for developers with tool use visualization
Hey HN! I built Experiment to solve a common frustration in LLM development: the lack of proper tools for prompt engineering experimentation. Here's what makes it different: Key Features: - Load and edit chat completion logs from CSV files - Fork and modify specific conversation entries - Run inference via Anthropic, Mistral, and OpenAI - Define custom tools using JSONSchema format - Visual tool usage analysis with collapsible, sorted key-value pairs - Full mobile support and available as installable PWA Technical Highlights: - Built with React using custom isomorphic architecture -…
What it does
In the maker’s words, at launch
Hey HN! I built Experiment to solve a common frustration in LLM development: the lack of proper tools for prompt engineering experimentation. Here's what makes it different: Key Features: - Load and edit chat completion logs from CSV files - Fork and modify specific conversation entries - Run inference via Anthropic, Mistral, and OpenAI - Define custom tools using JSONSchema format - Visual tool usage analysis with collapsible, sorted key-value pairs - Full mobile support and available as installable PWA Technical Highlights: - Built with React using custom isomorphic architecture - Implements streaming SSR and static HTML generation - Runs on GitHub Pages or as a native binary (Mac/Linux/Windows) - Progressive enhancement for optimal performance Why I Built This: Working with LLMs, I found existing solutions were either too basic (editing code directly) or too rigid (chat UIs with fixed tools). Experiment bridges this gap, offering a flexible middle ground for developers. Try it out: https://actualwitch.github.io/experiment GitHub: https://github.com/actualwitch/experiment Would love to hear your thoughts, especially on the architecture choices and developer experience!
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