Ask AI indexing runs in two production stages: source-hash changes update D1, post chunks, and FTS5 first; embedding checkpoints and a delete queue then let Vectorize catch up asynchronously. The two stores do not share one transaction.
Entering '我想找入門的ai課程' in Ask AI showed zero searched posts and triggered a refusal, while Related Reading recommended exactly the right article. The first fix addressed Chinese tokenization, the LIKE fallback, and the Vectorize data path. A second pass added short Han-and-number tokens, post metadata retrieval, and a rule that exposes sources only after both Validation and Critic pass.
Querying “認證” returned only ~10 hits while 149 files (509 occurrences) matched; 41 posts and 76 chunks were found via LIKE, but D1 chunks_fts had 0 rows and unicode61/trigram both returned 0 for 2-char CJK terms. Fix: LIKE fallback with char-level OR first, then trigram migration + pnpm sync, then pagination beyond the hard limit of 12.