OpenAI Responses API

Test OpenAI's Responses API from your browser — streaming, structured outputs, your key stays local.

OpenAI API keyGet one at platform.openai.comstays in your browser

Remember on this device (stored in localStorage). Off by default.

Model

max_output_tokens

temperature

Stream (SSE)store=true (keep for follow-ups)

Instructions (system prompt)

previous_response_id (optional — continues a stored conversation)

Input

At least one message is required.

~4 input tokens

The request goes directly from your browser to OpenAI — we don't proxy or log anything. Note: OpenAI may reject browser-origin calls from some networks; when that happens, click Copy as curl and run it from your terminal.

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