Libretto is a platform for optimizing and testing prompts for large language models. It helps you iterate faster on prompts and improve output accuracy with tools for automated evaluation and refinement.
How it works
After you sign up, you get a workspace with a dashboard, project list, and prompt tools. A built-in editor lets you create, test, and revise prompts in one place.
- Workspace with projects and prompt management
- Prompt editor for creating, testing, and updating requests
- Result monitoring and feedback tracking
How it compares
Compared with PromptLayer and PromptPerfect, Libretto focuses on test automation and scalability. It emphasizes deeper analytics and the ability to fit into an existing workflow.
Notes
Libretto is in beta, and some features are still being finalized. Training materials and user support are available, but there arenβt many public reviews yet. Pricing and plans may change.

