How Neo's Agent Architecture Evolved: From One Agent → Plan, Execute & Verify

Our first engineering post covered prompt caching, the infrastructure change that made long-running agentic tasks economically viable. That post assumed a multi-step, multi-agent system already existed. It did not exist on day one. When we started building Neo, the product was a single agent with a sandbox and a large toolset. Today, a typical task runs through optional planning, an Execution…