We cloned our visualization team — They live inside a subagent now

This post details the creation of a dedicated visualization subagent, separating visualization tools and logic from the main Hex agent. It describes the challenges of generalist agents in handling iterative visualization tasks, the structured handoff mechanism using visualization design principles (what/why vs. how), and the importance of 'agent eyes' (enhanced perception of output). It also outlines the iterative development workflow (structure first, then style) and the evaluation methodology using modified VisEvals for end-to-end and targeted bug fix testing.