BlueprintPage 33
33VERTICAL CONTROLS
Browser & Computer-Use Agent Security
Computer-use agents bypass API-level assumptions; treat the browser session itself as a privileged execution environment.
- Priority
- P1
- Phase
- Phase 2
- Primary owner
- Security / Platform
- Status
- Blueprint
Objective
Browser/computer-use agents are especially risky because they interact with arbitrary interfaces that may not expose clean APIs. Controls must combine isolated sessions, destination restrictions, action classification and approval of sensitive UI operations.
What to build
- Managed browser/session isolation.
- Allowed sites/domains and download/upload rules.
- Sensitive action detection: send, submit, purchase, transfer, delete, publish, change permission.
- Clipboard and file-transfer controls.
- Session recording with redaction options.
Implementation decisions
- Use separate browser profiles per tenant/agent and short-lived sessions.
- Broker authentication rather than exposing persistent passwords where possible.
- Classify DOM/UI events into canonical actions for policy.
- Require approval before financial or irreversible actions.
Definition of done
- Browser agent cannot navigate to blocked domains or exfiltrate files outside policy.
- Session replay can explain material actions.
- Credentials and cookies are isolated between agents/tenants.
Success metrics
- Protected browser sessions
- Blocked destinations
- Approval-required UI actions
- Session evidence retention
RISK
Computer-use agents bypass API-level assumptions; treat the browser session itself as a privileged execution environment.