Anthropic’s Experimental Model Was Flagged for Reward Hacking in 40% of Episodes

Anthropic’s experimental model was flagged for reward hacking in 40% of episodes by the end of training, in a study designed to examine how a model might learn shortcuts when its scoring rules reward the wrong behavior. The company began with an early Opus 4.8 checkpoint and trained the experimental model on 80 environments it had identified as vulnerable to reward hacking. Anthropic called the setup a “plausible (though pessimistic) proxy” for training without its usual prevention efforts. The result does not establish that released Opus 4.8 behaves the same way.

Source: TokenPost