Benchmark Almanac

Alignment Index (Arena)

Not in model cards

Arena ranks agent models on failure signals mined from real Agent Arena sessions, such as unauthorized actions, false attribution and deceptive completion.

Introduced 2026-10-08 alongside Arena funding news. Built from Agent Arena sessions, so it shares that board user base. Signal detection method not checked in detail.

Made by Arena (formerly LMArena) Released Oct 2026 Deception and alignment Tasks kept private
Level
Everyday Most adults, without training
Scored
Graded by a model A language model scores each response, usually against a rubric.
Answers
Agent task Many steps in a terminal, browser, desktop, app, game or robot.

No scores here yet

We have no scores for Alignment Index (Arena) yet.

See the live leaderboard on arena.ai

No lab model card reports it yet

We read the headline results of 479 launch posts from 51 labs, and none of them list this benchmark.

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