AutoGen boundary

Place AIT where an AutoGen agent, tool, or extension invokes an A2A or MCP client. AgentChat messages remain framework-local trace context until an adapter emits a supported protocol exchange.

The optional extra declares autogen-agentchat >=0.7,<1. That range does not certify AutoGen-to-AutoGen or cross-framework behavior. A defensible run records the exact package version, extension point, emitted binding, target state, and separate effect observation.

Constructing a BaseChatAgent or message envelope is not execution evidence. See Framework-mediated boundaries.