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promptperfect.beaglecorp.com
What it is
PromptPerfect is an open-source prompt optimizer from Beagle, available as a web app, Chrome extension, and API. In the web app, users submit a draft, choose an optimization mode, and receive rewritten text with an explanation of the changes. Modes include better, specific, cot, developer, research, beginner, product, and marketing. The Chrome extension is described as working on sites including ChatGPT and Gmail. Its API accepts a draft prompt and returns optimized text, an explanation, changes, the original text, provider, and model. Gemini, OpenAI, and Anthropic providers are supported. API keys can be supplied in the request body or as a Bearer token, with the Bearer token taking precedence. The homepage says keys stay in the browser and the project uses the MIT License. The Free plan costs nothing. Hosted Gemini anonymous callers share configured server-key quota.
Spec sheet
- Purpose
- PromptPerfect is an open-source prompt optimizer that teaches users why a rewritten prompt works.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- API
- The API accepts a draft prompt and returns an optimized version for use from a backend or scripts.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Security
- The homepage states that the user's API key never leaves their browser.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- License
- The homepage states that PromptPerfect is open source under the MIT License.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Maker
- The product is identified as being by Beagle and built by the Beagle Builder Program.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- API keys
- Users can provide a provider API key in the request body or as a Bearer token; the documentation says the Bearer token takes precedence if both are supplied.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- API response
- The API response includes optimized text, an explanation, changes, the raw text, provider, and model.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Browser extension
- The Chrome extension is described as working on sites including ChatGPT and Gmail.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Modes
- The documented optimization modes include better, specific, cot, developer, research, beginner, product, and marketing.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Optimization
- The web app lets users paste a prompt, pick a mode, optimize it, and learn why the rewrite works.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Providers
- The API supports Gemini, OpenAI, and Anthropic providers.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Rate limits
- The documentation says the codebase does not enforce a custom requests-per-minute counter on the synchronous API; throughput depends on the hosting platform and provider quotas.Read 7 Oct 2026 · promptperfect.beaglecorp.com
- Shared quota
- The hosted Gemini free tier uses configured server keys, and anonymous callers on that deployment share the quota.Read 7 Oct 2026 · promptperfect.beaglecorp.com
Plans and prices
Free Free Free; open-source Read 7 Oct 2026 · promptperfect.beaglecorp.com
Strong points and limits
Strong points
- Open-source under MIT License
- Web, extension, and API access
- Multiple documented optimization modes
- Supports three model providers
- API returns explanations and changes
Limits
- Anonymous hosted Gemini users share quota
- Throughput depends on hosting and provider quotas
- No custom synchronous request counter
Who it suits
PromptPerfect suits people refining prompts in a browser and developers calling optimization from scripts or backends. It also suits users who want explanations of how a rewritten prompt differs.
Verdict
PromptPerfect combines guided prompt rewriting with API access and multiple providers. Review quota and hosting constraints if you plan anonymous or automated API use.
Where Specifiction places it
- AI Prompt Generators#19 of 287.5
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