Scope comes first.
Each agent key can be limited to specific browser identities, domains and capabilities. A task narrows that authority again before the extension acts.
Browser scope
Choose which connected browser identities an agent may use.
Domain scope
Restrict navigation and actions to the sites a workflow actually needs.
Capability scope
Grant only the browser action classes required for the task.
Approval policy
Pause for a person where the workflow or action risk requires it.
Brain plans. Reflex handles confident routine steps.
Brain chooses the next useful subgoal. Reflex can execute bounded routine actions when confidence is high; uncertainty routes back instead of guessing.
Planning intelligence does not expand the browser permissions granted by the key or task contract.
Reusable knowledge without extra authority.
Skills capture where a workflow applies, its intent and repeatable stages. They help an agent reuse a known pattern while the same browser, domain and capability limits still apply.
Keep repeated workflow structure available without teaching the whole process again.
A Skill can guide work but cannot grant browser access the agent key does not already have.
Effects are checked, not assumed.
The extension verifies browser changes and returns durable task state. If BrowserPair cannot prove whether a side effect happened, recovery verifies or asks for resolution before another attempt.