Same Model, 10x the Score: The Hidden AI Bottleneck

Changing only the coding harness took Grok Code Fast 1 from 6.7% to 68.3%, and LangChain lifted GPT-5.2-Codex from 52.8% to 66.5% on Terminal Bench 2.0. 🎁 Get the resources from this video + my free AI builder course: https://skool.com/leonvanzyl 🚀 Go deeper inside Agentic Labs: AI coding courses, live Q&A, weekly challenges, and direct access to me: https://skool.com/agentic-labs #HarnessEngineering #LangChain #AICoding