Retrofit, don’t rebuild: Agentic overlays for transforming legacy enterprise services
TL;DR
AWS presents agentic overlays as a thin wrapper layer that turns existing REST services into agent-capable components without rewriting core business logic. The overlays expose REST endpoints as MCP-compatible tools while also letting services participate in A2A interactions between agents. The target is enterprise teams that want agent workflows on top of legacy services without duplicating code or running parallel infrastructure.
Nauti's Take
This is the rare enterprise AI pitch that actually respects reality: do not rebuild the estate, wrap the old API world so agents can use it. The hard part is governance, failure modes, and permissions.
Wrap blindly and you do not get an agent stack. You get automated legacy spaghetti.
Briefingshow
Most enterprises are not starting from scratch; they already have REST estates with compliance rules, auth flows, monitoring, and critical business logic. An overlay approach lets agent systems connect to those stable services instead of replacing them. The real value appears when MCP and A2A become an access layer over existing capabilities rather than another isolated platform.
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