HackerNews Is Talking About Fast AI Agent Tools — Here's What They're Missing

HackerNews Is Talking About Fast AI Agent Tools — Here's What They're Missing A Cursor blog post about fast regex search for agent tools just hit the HackerNews front page. Here's why developers are excited — and what the full picture looks like. If you've been on HackerNews recently, you may have seen Cursor's deep-dive into fast regex search for agent tools . The post covers how they built inverted indexes to replace ripgrep for large monorepos — because when your AI agent is calling grep thousands of times, even 15-second searches become a dealbreaker. The HN community loved it. Developers are building AI agents that use tools — search, code execution, data retrieval — and speed matters at every layer . But here's what the discussion mostly missed: fast search is only half the equation . The Performance Bottleneck Nobody Talks About When your AI agent runs a loop — search → think → act → repeat — the bottleneck isn't always the search. It's often the AI inference step . If your agen