Decision framework
Use REST API when you need low-level control, custom payloads, and one-off endpoint work. Use MCP when AI assistants must execute repeatable workflows with safe tool boundaries.
REST vs MCP in practice
| Dimension | REST API | MCP |
|---|---|---|
| Speed for assistants | Lower (custom plumbing) | Higher (tool contracts ready) |
| Governance | Manual per endpoint | Centralized per tool |
| Developer flexibility | Maximum | High, with standards |
Recommended hybrid architecture
- Build/keep core primitives with REST.
- Expose stable business actions as MCP tools.
- Route chat assistants through MCP only.
- Keep analytics, auth, and billing checks in server middleware.
Common mistakes to avoid
- Giving assistants raw unrestricted REST access.
- Skipping webhook path validation for self-hosted portals.
- No retry policy for external AI generation dependencies.
FAQ
Do I lose control with MCP?
No. You gain safer control through explicit and testable tool interfaces.
Should we migrate all REST calls to MCP?
No. Keep infrastructure and low-level operations in REST, and surface assistant-facing actions through MCP.