Debugging a Multi-Agent System That Costs 4x More Than Planned

A multi-agent research-report system was designed assuming 5 parallel workers plus a supervisor and synthesis agent would cost about the same as one agent working serially, similar to the worked example in this subject. In production, it's costing roughly 4x a comparable serial baseline, and the team isn't sure why.

1. List the concrete places the cost could be blowing up, in priority order of how you'd investigate them.
2. For each, describe the observable signal that would confirm it's the culprit.
3. Propose the fix for the two most likely causes.