[DeepSeek Harness Developer Preview v0.1 Open Testing] The developer preview version (v0.1) of DeepSeek Harness is now open for testing to Harness developers worldwide, with its source code simultaneously released under the MIT license. DeepSeek Harness adopts a 'everything is a plugin' design philosophy. It uses a plugin-based open architecture to build Agent Harness: all Agent capabilities—including models, tools, skills, sessions, sandboxes, storage, loops, scheduling, UI, etc.—are composed of plugins, allowing for free replacement and flexible recombination.