PromptDesk is 100% free and open-source minimalist tool to facilitate the creation, organization, integration, and evaluation of prompts, prompt-based applications, agents and Large Language Models (LLMs). Features include:

OpenAI-like minimalist prompt builder Prompt variable and logic support with Handlebars.js syntax Complete audit log of all API calls Unlimited vendor-agnostic LLM API integrations Environment variables support Easy to set up and integrate (5 minutes) Community-driven