MCP Security: What Product and Engineering Teams Must Design Before Launch

Why security comes first

The value of an agent is its ability to take action. The risk is that those actions may reach sensitive data, critical systems, or irreversible workflows. Security must shape the architecture from the beginning.

The control areas

Every agent implementation needs: identity and authentication, role-based access, least-privilege tool exposure, human-in-the-loop approvals, data isolation, secret management, input validation, prompt-injection resistance, action logging, rate and scope limits, reversible changes, and incident response planning.

Risk classification

Not all actions carry the same risk. Classify every tool by impact: low risk (read-only, non-sensitive), moderate risk (low-impact, reversible), high risk (sensitive data, configuration changes, financial impact), and critical risk (destructive, irreversible, privileged, regulated).

Design before deployment

Each risk level should define required identity assurance, permission model, human approval requirements, logging requirements, recovery processes, and testing requirements. This framework ensures consistency and prevents gaps.