Harness

What it is

A Claude Code plugin and meta-skill that takes a plain description of your domain and generates a set of specialized agent definitions, the skills they use, and an orchestrator that wires them together. It chooses among architecture patterns such as pipeline, fan-out, producer-reviewer, and supervisor, and picks workflow scripts, persistent agents, or sub-agent delegation based on how the work flows. Developers who rely on Claude Code use it to scaffold .claude/agents and .claude/skills for a codebase, test them with A/B evals, and refine them later from usage feedback with an evolve command.