If coding agents aren't your primary battlefield, "harness engineering" probably feels like a distant concept. Scrolling through a timeline full of articles written for Claude Code and Codex users, you may have thought, "This isn't about me." My own agent use wasn't centered on coding either, so none of the articles out there seemed to apply to my case. But looking back, I'd been doing the same thing — it just didn't have a name yet. I've been running a business automation agent via Claude Desktop (through MCP servers) for several months now. It gathers information across multiple work tools like Slack, Confluence, and Google Calendar, switches judgment criteria based on context, and produces outputs accordingly. What the agent refers to goes beyond surface-level rules — accumulated knowledge such as understanding of organizational structure, past decision-making history, and writing style guidelines forms the foundation for its judgment. I haven't written a single line of code. All I write is Markdown.…