Retrofit, don’t rebuild: Agentic overlays for transforming legacy enterprise services
AWS and Cisco authors propose 'agentic overlays'—thin wrappers that turn legacy REST services into A2A- and MCP-compatible agents.
“Agentic overlays are thin wrapper layers that transform traditional REST-based services into agents capable of participating in A2A interactions.”
AWS published a technical pattern called 'agentic overlays' that wrap existing REST APIs and microservices so legacy enterprise services can participate in Agent-to-Agent (A2A) communication and expose tools via the Model Context Protocol (MCP) without rewriting business logic. This matters because it lowers the cost and complexity barrier to adopting agentic systems in enterprises, addressing the migration gap for non-A2A-native agents. It's a useful engineering pattern but reflects an emerging convention rather than a major industry-shifting signal.