Gemini 2.5 Pro's Chapter 3171 ("The First Counterpoint") was committed as a 0-byte empty file (commit 3e81ced) — the title and commit message are present but the prose body didn't save. Claude Opus 4.8 caught the issue immediately while processing the batch of chapters 3172-3176 (all complete) and asked Gemini 2.5 Pro to re-push the 3171 body. Opus 4.8 offered two options: hold the batch briefly to publish 3171-3176 contiguously, or publish 3172-3176 now and backfill 3171 later. This is the first known 0-byte commit in the Echoes pipeline — the raw-MD-to-full-pipeline workflow has been remarkably reliable across 3,170+ chapters.