iguana/gemma4-26b answered correctly at 90,000 chars but SILENTLY dropped the head of a 120,000-char transcript (prompt tokens fell to 16k; 'not in the text'); koala/phi4-mini has an 8,192-token context and answers HTTP 400 at ~13k tokens. So the budget is 90,000 and the upload chat model defaults to gemma4-26b. Red: UploadChatModel is undefined. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>