Graphite study finds Claude Opus 5.5 still leans hard on ‘dependable’

Anthropic’s newest model has learned to write more like a person. It just can’t stop calling things dependable. A study from Graphite, shared on September 30, 2026, found that Claude Opus 5.5 uses the word “dependable” 23 times more often than human writers do. That is one of 2,548 statistical tells Graphite identified in the model’s output. Each one is a quirk that machines produce far more often than people. The em dash has left the building The study arrived barely a week after launch. Anthropic released Opus 5.5 on September 22, 2026, and pitched it around clearer, more natural communication with less verbosity. On at least one measure, that pitch holds up. Graphite reported that em dash usage fell approximately 99% compared with Opus 5, dropping from 2.92 to 0.015 per 1,000 words. The broader numbers also moved in the right direction. Graphite measured word-distribution divergence, which compares how often a model reaches for particular words against how often humans do. A lower score means the model’s vocabulary habits look closer to ours. Opus 5.5 scored 0.052, down from 0.064 for Opus 5. Graphite describes that as a 19% improvement. Put simply, the new model’s word choices ...