AI Agent vs. AI Harness: Where Memory Actually Lives (opens in new tab)

The model decides what to do\. The harness stores memory, runs tools, enforces rules, and keeps the agent working\. Part 2 named the building blocks: sessions, Memory Bank, runtime, identity\. This part draws the boundary around them: which pieces belong to the agent’s behavior, and which pieces belong to the harness that operates it\. When an AI agent reads a file, who actually reads it? Not the model\. The model decides that reading the file would help\. The harness checks the path, runs th...