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GlossaryAI in TestingChunking Strategy Testing
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Chunking Strategy Testing

Chunking strategy testing evaluates how a RAG system's choice of chunk size, overlap, and splitting logic (by paragraph, sentence, token count, or semantic boundary) affects retrieval quality and downstream answer accuracy — since the same source documents can perform very differently depending on how they're cut into retrievable pieces.

Chunking decisions are easy to treat as a fixed implementation detail set once and forgotten, but they directly shape what's even possible to retrieve correctly later: chunks too small lose surrounding context a chunk needs to make sense on its own (a table row with no header, a pronoun with no referent), while chunks too large dilute relevance and drag in unrelated content alongside the useful part, hurting both precision and the amount of irrelevant noise the model has to filter.

Testing usually means holding the rest of the RAG pipeline fixed and varying only the chunking strategy — size, overlap percentage, and split boundary logic — then re-measuring retrieval precision/recall and final answer accuracy on the same labeled query set, to isolate chunking's actual effect from everything else in the system.

Document structure matters here too: a strategy tuned for prose (splitting on paragraph boundaries) often performs badly on tables, code, or structured data, so a single chunking config tested only against one document type can quietly underperform once real, mixed content hits it.