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Author by chat
Describe the agent you want in plain language. A reasoning model writes the first system prompt, then iterates with you turn by turn.
Craft system prompts that actually behave.
Prompt Studio is where you write, test, and version the prompts that power your AI agents — from first draft to production, all in one quiet workspace.
Why we built this
Every client wants the agent to behave differently.
One wants formal replies. Another wants short answers only. A third changes their mind weekly. Reshaping an agent's system prompt for every client request means digging through a wall of text, editing carefully, and hoping nothing breaks. Prompt Studio turns that afternoon of careful edits into a few minutes of chat, a quick test, and a saved version you can always roll back to.
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Test with any model
Stress-test your prompt against any model on OpenRouter — tweak temperature, wire up tools, and watch the reasoning unfold live.
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Version every revision
Each edit is a version you can label, revisit, and branch from. Organize prompts into projects with their own variables and tools.
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Variables & tools
Define template variables and OpenAI-style tool schemas once, then reuse them across the editor and the tester.
Bring your own key, ship your own prompts.
Everything runs in your browser against your OpenRouter key. No prompts leave your machine except to the model you choose.
Open Studio →