PromptEval

PromptEval is a tool designed to assess and improve the quality of AI prompts, focusing on structural evaluation before prompts are deployed in production. It addresses common issues such as vague instructions, insufficient specificity, poor structure, and lack of robustness in prompts used with language models. The platform provides a scoring system that evaluates prompts across four key dimensions: clarity, specificity, structure, and robustness. Each dimension is measured independently, and the tool identifies exactly which aspect is failing and why, offering targeted feedback and suggestions for improvement.

The platform offers several features to support prompt development and maintenance. Users can receive a detailed evaluation report with a numeric score from 0 to 100, highlighting critical errors and suggesting improved prompt rewrites. A fix iterator allows users to address specific failing instructions with minimal edits. PromptEval includes a versioning library, enabling users to save, track, and compare prompt versions, with each version maintaining its score, diff, and change context for traceability. The tool supports serving prompts via an API, allowing updates without redeployment. It also provides a playground for batch A/B testing of prompts using the user's own API key, supporting up to seven evaluation criteria and radar chart visualizations. A comparison feature lets users analyze prompt versions side by side, automatically detecting regressions and pinpointing their causes.

PromptEval integrates with GitHub Actions, enabling a regression gate in continuous integration workflows. This feature evaluates prompts on pull requests and can block merges if the prompt's score drops, if there are conflicting instructions, or if the prompt regresses compared to the production version. This functionality is available on the Pro plan and above.

The tool is intended for individuals and teams who manage prompts in production environments, including solo developers, daily AI practitioners, and larger teams requiring approval workflows and audit logs. PromptEval is delivered as a web-based platform with API access. Pricing includes a free plan with three web evaluations per month and limited API usage, a Basic plan at $9 per month, a Pro plan at $19 per month with expanded features, and a Team plan at $49 per month offering workspaces, roles, approval flows, and audit logs. The service also provides daily training sessions for learning prompt engineering on real workplace tasks.