Anthropic Messages API

Send prompts to Claude from your browser — streaming, system prompts, your key stays local.

Anthropic API keyGet one at console.anthropic.comstays in your browser

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

Model

max_tokens

temperature

stream

SSE

System prompt (optional)

Messages

At least one user message is required.

~4 input tokens

Your key and prompts go straight from this browser to Anthropic — nothing touches our server. By default your key is kept in memory only; checking "Remember on this device" stores it in localStorage for your convenience.

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