2 stories

Engineering

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 agent that delegates to parallel specialized subagents, and a verification loop that can re-run w

How We Cut LLM Costs by 59% With Prompt Caching

At ProjectDiscovery, we've been building Neo, an autonomous security testing platform that runs multi-agent, multi-step workflows, routinely executing 20-40+ LLM steps per task. Vulnerability assessments, code reviews, and security audits at scale, enabling continuous testing across the entire development lifecycle. When we launched, our LLM costs were staggering. A single complex task with Opus 4.5 could consume 60 million tokens. Then we implemented prompt caching. Here's what changed: