Anthropic’s ClaudeDevs account announced the update, which adds custom themes to local Claude Code sessions in the desktop app. Mods can change interface colors and place static or animated backdrops behind the conversation. Developers can write a theme, ask Claude to generate one from a natural-language description, or modify the ready-made theme-examples plugin.

Mods reach behind the transcript

Claude Code mods are plugins built from function hooks that run within a session. They can render panes, prompt-area bands, status lines and notifications, as well as inspect, rewrite or block tool calls before execution. The new $.theme API adds an app-level backdrop, while ui.render hooks control the colors and styling of individual interface elements.

Local sessions get it first

Security: A theme remains executable mod code and receives the same machine access as Claude Code. Review its source and install themes only from trusted publishers.

Build from scratch or install

  1. Update the desktop app and confirm that Claude Code is running version 2.1.319 or later.
  2. Start with theme-examples, ask Claude to generate a mod, or create one manually.
  3. Call $.theme.set with the backdrop the client should render.
  4. Use ui.render hooks to style render sites such as UserMessage, AssistantMessage, Spinner and Pane.
  5. Call $.theme.clear when the backdrop should be removed.

The community-maintained matcra587/claude-themes marketplace already packages palettes including Dracula, Catppuccin, Gruvbox, Nord and Tokyo Night. These commands register that marketplace, install its Dracula theme and open the theme selector:

/plugin marketplace add matcra587/claude-themes
/plugin install dracula@claude-themes
/theme

The desktop surface opens up

The new backdrop layer expands the desktop Code tab, where mods previously had fewer visual controls than in the terminal transcript. Combining an app-level canvas with component-level render hooks lets one theme cover the conversation background, messages, panes and activity indicators. Developers can now align Claude Code with an editor palette or create visual states for different workflows.

Plugin authors can use the mods overview for architecture and the interface reference for hooks and API details. Themes should be tested in a local desktop session until Anthropic enables cloud-session support.