Lena — ask a knowledge base

A live text demo of a production agentic RAG assistant. Lena decides which retrieval tool to call, searches a knowledge base built from ~40 curated AI & coding YouTube channels, and answers grounded, with cited sources — refusing to invent when the corpus has nothing.

Built by Bastian Brand. The production version is a voice agent (VAPI); this is the same brain exposed as text, with actions disabled and requests rate-limited. Ask about recent developments in AI and coding — the answers come only from the knowledge base and name their sources.
What's new in AI coding this week?
Which channels do you cover?
What are people saying about AI agents?
Any recent videos from Fireship?