Brian McManus August 16th, 2026 No Plan Survives First Contact What preparing an autonomous agent for HalCTF at DEF CON 34 taught me about model routing, harness design, and adaptation Seventeen years after my last DEF CON, I knew almost immediately where I would spend every waking hour: the AI Village, competing in HalCTF. In a traditional capture-the-flag competition, or CTF, you hack a vulnerable system and score points by extracting flags: secret strings that prove you got in. HalCTF, the…