Why AI Should Never Fill Your W-9: The Case for Deterministic PDF Writing

AI excels at reading documents but creates serious compliance risks when writing them. Using a probabilistic language model to fill tax forms, insurance documents, or regulatory filings produces filled values that cannot be defended in audits—regulators won't accept 'the model was 97% confident' as justification. The solution is a division of labor: use AI for data extraction but apply deterministic, template-based filling for the actual form completion, ensuring every value is traceable and defensible.