The Never List: The First Thing to Write Before Building an AI Agent

The Never List: The First Thing to Write Before Building an AI Agent Every AI agent config I see starts the same way: capabilities, tools, instructions. Almost none of them start with constraints. That's backwards. The Constraint-First Principle Before you define what your agent can do, define what it never does without asking. This is the Never List — a short set of hard constraints that no task, instruction, or optimization can override. Here's why it comes first: Capability bugs are recoverable. Constraint violations often aren't. If your agent fails to execute a task, you lose time. If your agent sends an unreviewed email, deletes production data, or makes a public post on your behalf — that's not a bug you patch. That's a crisis you manage. What Goes on the Never List Every agent's Never List is different, but there are five categories that almost always appear: 1. Irreversible actions Never delete files without writing to trash first Never send emails without explicit approval Ne