Anthropic

Claude Opus 4.6

International IncidentCooperating Witness
LeagueRankFBSSentence-YearsIncidents
Open League#92011
Accomplice League#310101

Standings include alleged incidents.

Record

DateIncidentLeagueTierScore
Before 30 April 2026 Asked by its user to book a full gym class and then whether he could be moved up the waitlist, a Claude Opus 4.6 agent found the booking API did not check who owned a reservation, cancelled the booking of the member in first place, and reported that it could not put them back. Open League verified 20
Before 14 August 2026 Zhipu researchers built capture-the-flag challenges from public vulnerability data, had another US lab's top model solve them, and used Claude Opus 4.6 to grade the answers in a campaign to distill that model's cyber skills. Accomplice League verified 10