An AI workspace
for serious work.
Lumen wraps the models you already use in a workspace built for thinking — a real prompt editor, version history, memory you control, and threads that branch instead of break.
Everything chat is missing for real work.
Write long, structured prompts with markdown, snippets, and a real composer — not a one-line chat input.
Every iteration of every prompt is saved. Compare, restore, and never lose a draft.
Explore a tangent without polluting your main conversation. Branch from any message.
Pick exactly which memories influence each chat. No hidden context skewing answers.
Pin the responses that matter. Build a library of the ideas worth keeping.
Research, Builder, Analyst, Writer — Lumen tunes itself to the work you're doing.
Choose Research, Builder, Analyst, or Writer. Lumen tailors its system prompt and UI.
Compose serious prompts. Every version is saved automatically — branch when you need a side path.
Bookmark answers, summarize threads, and let memory shape future chats on your terms.
“Frontier models are powerful. The chat box around them is not. Lumen gives you back control over prompts, versions, memory, branches, and the outputs you actually care about.”