Step 1 — Choose your target LLM ? Prompt Designer uses this to tailor each generated prompt for your model's
specific response patterns. Different models respond differently
to the same prompt structure.
Which model are you writing prompts for?
OpenAI API Key ? Used to run your examples through the actual model and compute real
token confidence scores. Without a key, results fall back to
Claude's heuristic estimates — still useful, but not empirical. optional — enables empirical testing
Your key is sent directly to o3 and never stored on our server.