16x Prompt is a web-based tool that streamlines AI coding workflows by managing source code context and generating optimized prompts for ChatGPT, Claude, Gemini, and other LLMs. It supports structured prompt creation, custom instructions, and token limit tracking. Users can copy prompts or send them via API with their own keys. The tool includes a code editing feature that applies changes safely with visual diffs and backups. It also offers workspaces for organizing multiple repositories and side-by-side comparison of LLM.