Direct API favors maximum implementation control.
A direct integration is appropriate when your product needs a custom data model, deterministic jobs, high-volume exports, or infrastructure policies that require owning authentication and execution.
MCP favors reusable access from AI workspaces.
MCP provides discovery and invocation conventions that ChatGPT, Claude, Codex, and other clients can share. It does not remove the need for strong server-side authorization and validation.
Managed MCP trades infrastructure for product constraints.
A managed layer can absorb API migrations, credential operations, workflow design, and approval UI. Evaluate tool coverage, data retention, scopes, logs, and export paths before choosing it.