The gpt-oss harmony format generates internal control tokens
(<|channel|>, <|start|>, <|end|>, <|message|>) that should not appear
in the user-facing output. Additionally, <|end|> marks the end of a
response segment but was not in the model's EOS list, causing the
model to self-prompt into analysis channels and loop.
Fix: treat <|end|> as a stop token, skip all harmony special tokens
from the output stream.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Gahow Wang
3ee8df2c0f