DeepSeek Harness adds Creator Mode for building live UI plugins in chat

DeepSeek introduced Creator Mode in DeepSeek Harness on 2 November 2026, expanding its MIT-licensed desktop and local web agent environment so users can reshape the workspace itself through plain prompts. Built on the Cordis modularity framework (arXiv:2608.25512), DeepSeek Harness treats tools, model providers, skills, memory and visual panels as independent plugins rather than fixed application code.

Selecting Creator Mode in the session picker alongside Standard, PTC batch tool execution and Minimal terminal mode loads the cordis-plugin-development skill. When prompted for a new tool or panel, the agent inspects active runtime services and UI slots such as shell.overlay and conversation.view, writes the plugin code, checks it with node --check and oxlint, applies scoped interface tokens through ctx.theme.overrideTokens, and hot-reloads the extension into the live session without a restart.

Showcase plugins and availability

DeepSeek’s launch video demonstrates seven custom interfaces built inside Creator Mode: a Style Lab theme editor, a Sticky Wall spatial canvas, a Poster Studio layout tool, a browser-style Video Editor, the Fuyu 3D voxel island sandbox, an arXiv paper annotator and an interactive Transformer 3D Lab. Desktop installers ship for macOS on Apple silicon and 64-bit Windows, while npx @deepseek-ai/dsh web serves the same interface locally on 127.0.0.1:3080 across Linux, macOS and Windows. Users connect their own API keys from DeepSeek or other model providers; DeepSeek charges no separate Harness licence fee.