Harness Engineer

This skill creates a complete, agent-first project foundation based on Harness Engineering principles. It works in TWO modes:

• Greenfield — New project from scratch. Full product discovery, PRD, scaffold, everything.
• Retrofit — Existing project. Analyze the codebase, add harness layer on top. No scaffold generation, no long-task bootstrap. Future work flows through plan mode.

The philosophy: AGENTS.md is a table of contents, not an encyclopedia. Keep it concise, pointing to deeper sources of truth. All project knowledge lives in the repo as versioned, discoverable artifacts — because if an agent can't see it, it doesn't exist. Generated AGENTS.md / CLAUDE.md always include fixed Interaction Rules and fixed Iron Rules; project-specific sections fill in the rest.

For humans maintaining this skill repo itself, start at docs/index.md.