Observations on Opus model Role Token changes

Ratter · x · 2026-09-01

The author observes a change in Opus's training format, which used to be plain text \n\nHuman: / \n\nAssistant:. This seems to have changed around version 4.8.

Now the model can output \n\nHuman: without stopping generation, suggesting a shift in the underlying Role Token handling mechanism.

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