Understanding Agent-to-Agent (A2A) handoffs in the activity ledger
Every time Camelia hands work to a specialist, the handoff is recorded as an Agent-to-Agent (A2A) envelope in your project's activity ledger. This is what makes delegation transparent and traceable.
What gets logged
When Camelia calls spawn_subagent, the handoff is logged as an A2A envelope: a Put from Camelia to the role, and a Push from the role back to Camelia. In other words, the ledger captures both the assignment and the return of work, not just a single event.
Where it shows up
These A2A envelopes feed the Conversations node graphs, so a delegation appears as a visible exchange between Camelia and the specialist rather than an opaque step. This is part of HIIE's broader transparency model, where Camelia's own chat stream is parsed into a process trace with distinct event kinds — reasoning, action, output, gate, and warning.
Flows log the same way
Flows use the identical mechanism. Each flow step logs an A2A envelope, so an entire multi-step run appears as one coherent conversation in the node graphs. A research step, a design step, and a manufacturing step in the same flow all leave their own envelopes, letting you follow the chain of work end to end.
Why it matters
The activity ledger gives you an audit trail: who was asked to do what, and what came back. Combined with smart-labeled saved artifacts, it means you can reconstruct how a deliverable was produced — which specialist contributed, and in what order. If something looks off in an output, the A2A trail is the place to see exactly which role generated it.