Parallel Model Testing
Send a single prompt template to GPT-4, Claude 3, and Gemini simultaneously. Instantly compare raw JSON outputs, latency metrics, and exact token consumption side-by-side without managing multiple browser tabs.
Iterate. Compare. Benchmark.
A desktop client for testing, grading, and benchmarking prompts across major LLMs.
A Dedicated Prompt Workbench.
A desktop environment that connects directly to major LLM APIs using your own keys. Your test datasets, variables, and evaluation histories are written strictly to your local drive, freeing you from cloud subscriptions and vendor lock-in.
Bring Your Own Keys
Connect directly to major LLM providers. Your API credentials, prompt history, and proprietary datasets are stored purely in your local SQLite database.
Automatic Prompt Checkpointing
Every iteration is automatically saved to your local database. Fork a prompt to test a new variable, track the exact changes that improved the output, and easily revert to past configurations.
Deterministic Model Benchmarking
Set up strict baseline metrics using your custom datasets.
Protect your workflow from unexpected regressions when LLMs update.
Model Benchmarking
Run your prompt against a full test dataset across multiple models at once. Review the batch outputs side-by-side and assign pass/fail grades to see exactly which model handles your edge cases.
Version Control for Your Prompts.
Keep a clean history of your iterations. Fork a prompt to test a new variable, track the changes, and easily switch back to past versions.
Request-Level Debugging.
Chat interfaces hide the details. Inspect raw API responses, latency stats, and exact token usage for every single request.
Model Benchmarking
Run your prompt against a full test dataset across multiple models at once. Review the batch outputs side-by-side and assign pass/fail grades to see exactly which model handles your edge cases.
Bring Your Own Keys.
Keep your credentials on your machine. Your keys are encrypted via your OS keyring, saved to your local database, and sent strictly to the providers. We track nothing.
Manage Models & Parameters.
Connect your APIs, toggle active models, and adjust request parameters all from one central interface.
1. Provider Setup
Bring your own keys. Connect OpenAI, Anthropic, Mistral, Gemini and XAI in seconds. Toggle models on/off to keep your workspace clean.
2. Inference Settings
Adjust temperature, top_p, and frequency penalties to observe how different constraints impact your prompt results.
Under the Hood
We chose Electron for cross-platform support, but kept the stack as simple as possible.
Native Web Components
No heavy frameworks overhead. We built the interface using standard HTML, CSS, and vanilla JavaScript.
Local SQLite Database
Your data lives in a standard SQLite file on your disk. Backup, version control, or delete it whenever you want.
tech_stack.json
JSON
{
"runtime": "Electron",
"security": "Context Isolated",
"frontend": "Vanilla JS + Web Components",
"database": "SQLite3 (Local-only)"
}
LIVE DEMO
Concurrent Model Testing.
Evaluating Anthropic, Mistral, OpenAI, and xAI side-by-side. No browser tabs, no manual copy-pasting.
Ship AI Features With Certainty.
Batch-test your datasets and prove model reliability before hitting production.
Learn about our permanent licensing and early-adopter pricing:
View License Details →