DeepSeek Harness v0.2.1-alpha.1 adds an experimental Claude Code Mods bridge and lets agents start creating plugins

What changed

DeepSeek Harness released prerelease v0.2.1-alpha.1 on October 3. It adds an experimental Claude Code Mods compatibility layer intended to test whether the Mods API is broadly a subset of DSH's plugin capabilities. The release explicitly says the goal is not yet complete, practical compatibility, and the compatibility documentation lists behavioral differences from native Claude Code. The same alpha also adds a “Let Agent create a plugin” entry, a Web --public-url option, an optional developer-tools bundle, and multiple session, desktop and plugin-runtime fixes.