Chunking

Operator uses chunking_strategy=by_title so chunks respect section structure, but the source was partitioned with fast and has few real Title elements.

by_title starts new chunks at Title/section boundaries — it depends on accurate Title detection, which comes from good partitioning (often hi_res). Verify Titles exist before relying on by_title; otherwise chunks degrade toward size-only splits.

RAG recall is poor at chunk boundaries; the agent sets overlap to a very large value to compensate, ballooning the index.

Set overlap to a modest fraction of max_characters to preserve boundary context without exploding index size or duplicating content across many chunks. Tune against retrieval metrics rather than maximizing overlap blindly.

With by_title, the operator expects sections to be capped at page boundaries but a section legitimately spans pages and gets split unexpectedly.

Control cross-page section behavior with multipage_sections: allow a by_title section to span pages when the document structure warrants, or restrict it to single pages when page locality matters. Choose deliberately rather than accepting the default blindly.