Permission mode is a setting that controls which actions a tool or AI assistant may take, and when it must ask a person first. One mode might allow reading project files but pause before changing them.
Think of a visitor pass for a building: it may open some doors while keeping more sensitive rooms locked. The setting helps define what the assistant can do in its working environment.
Permission modes differ across tools, so read what a mode allows before selecting it. Approval prompts help, but they do not replace checking whether an action is appropriate.