Modular diagram of the DeepSeek Harness plugin architecture: agent loop, model, tools, sandbox, and session log as swappable hexagon modules

DeepSeek Harness: The Agent Runtime Where Everything Is a Plugin

DeepSeek Harness hit 195K stars in two weeks. It’s less a coding agent than the machinery a coding agent gets assembled from: everything is a plugin, built on Cordis, with append-only session logs and subagents that can delegate to competitors. What’s real, what still hurts.

August 25, 2026 · 10 min · 1958 words · Marco