Stop juggling tabs and guessing which AI model is best. Nexim AI Playground puts Gemini, OpenAI, and OpenRouter (Llama, Claude, DeepSeek) into one simple workspace. You can tweak system prompts and temperatures side-by-side to see real-time results. Best of all? Your API keys stay local to your browser, so your data stays private. It tracks tokens and speed for you, making prompt engineering feel less like a chore and more like a breeze. It’s AI testing, but actually organized.