Harness Engineering — A Practical Guide to Safe AI Agent Operations

Sat, 04 Apr 2026 00:00:00 +0900

Harness Engineering — A Practical Guide to Safe AI Agent Operations#

2026-04-04

Why I Wrote This#

I actively use AI agents (Cursor, Claude Code, etc.) across multiple projects. At first, having an agent write code was impressive enough on its own. But as I integrated them more deeply into real projects, I kept running into recurring problems.

Every time I open a new session, the agent forgets the project conventions
It repeats the same mistakes today that we already solved yesterday
The quality of agent-generated code fluctuates wildly between sessions
When managing multiple projects, I have to repeat the same setup for each one

The root cause of these problems wasn’t a lack of agent intelligence — it was that the environment surrounding the agent was not properly set up. As 2026 arrived, this concern spread across the industry and began to be systematized under the name “harness engineering.”

I Decided to Call Them Harness Skills — Breaking the Illusion of Doing Well and Opening Up My Harness

Mon, 08 Jun 2026 00:00:00 +0900

I Decided to Call Them Harness Skills — Breaking the Illusion of Doing Well and Opening Up My Harness#

2026-06-08

Facing Things Without a Name#

When I first saw something called LLM Wiki, and then GStack, the first thing that came to mind was surprisingly: “What should I even call these?”