Cartoonishly Serious
A desktop AI chat client where the canvas renders your reply, the tools touch the world, and the mascot is a crab cupcake you re-shape by talking to it.
Ask for a thank-you note, a flow field, a single-page app — the last runnable code block in the reply renders live in the right pane. Sandboxed iframe, opaque origin, no copy-paste into CodePen. The model isn't describing what it would do. It's doing it, while you read.
Anthropic OAuth (Claude.ai subscription), OpenAI OAuth (ChatGPT subscription via Codex), GitHub Copilot device flow, plus API keys for xAI, Gemini, OpenRouter. One client, seven backbones. The 9-tool catalog works across all of them — even ChatGPT-OAuth on the Codex Responses API. Switch mid-conversation. Bring the friend that talks like you.
The kawaii crab cupcake at the top of this page? That's the default. Yours can be anything. Enter the dressup canvas, ask the model to change a thing, save it as your CUPCLAW'd. Generate real sprite art via xAI Flux or OpenAI image gen — your mascot, drawn by the AI you chose, kept on your machine.
Nine builtins out of the box: bash, webfetch, read, write, edit, glob, grep, generate_image (multi-backend), transcribe_audio (Whisper). Plus any MCP server you point it at. Open source, closed plugins — every tool runs on your machine, in your home directory, with your eyes on it.
Every other chat app treats AI like a vending machine. You queue. You pay. You get the cold soda. We think that's a waste of a miracle. Kosmos is your living room — the AI lives here, it knows your CLAW'd, it remembers your projects, and the canvas does what your imagination tells it. We made the thing we wanted. Then we put a face on it. The face is a crab cupcake. We're aware. We're keeping it.
Free during open beta. Self-updating once installed. Closed plugins, open client.