PromptPerfect

What PromptPerfect is

PromptPerfect is a free, open-source prompt optimizer available on the web, as a Chrome extension, and through an API. In the web app, users submit a draft, choose an optimization mode, and receive a rewritten prompt with an explanation of why the changes may work. Documented modes include better, specific, cot, developer, research, beginner, product, and marketing. The Chrome extension is described as working on sites including ChatGPT and Gmail. For backend or script use, the API accepts a draft and returns optimized text, an explanation, changes, the original text, provider, and model. It supports Gemini, OpenAI, and Anthropic. A provider key can be sent in the request body or as a Bearer token; the Bearer token takes precedence when both are present. The homepage says API keys stay in the browser and identifies the project as MIT-licensed. The hosted Gemini free tier uses configured server keys, so anonymous users on that deployment share its quota.

Who it suits

It suits people who want to refine prompts through a web app, Chrome extension, or API, with an explanation of the rewrite. Developers can use it with Gemini, OpenAI, or Anthropic providers.

Limits

Anonymous callers on the hosted Gemini free tier share the configured server-key quota. The synchronous API does not enforce a custom requests-per-minute counter; throughput depends on the hosting platform and provider quotas.

Getting started

1. Open https://promptperfect.beaglecorp.com/ to use the web app.
2. Paste a draft prompt and choose an optimization mode.
3. Use the Chrome extension on supported sites such as ChatGPT or Gmail.
4. For API use, send a draft prompt and select a supported provider.
5. Provide a provider API key in the request body or as a Bearer token.

Verdict

PromptPerfect combines prompt rewriting with explanations across its web app, extension, and API. The shared quota on the hosted Gemini free tier is worth noting for anonymous callers.