Report #94336
[cost\_intel] Using reasoning models for all structured extraction is 20x too expensive
Use cheap instruct model for initial extraction \(GPT-4o-mini or Haiku\), then use reasoning model only as a validator/fix-up pass on failed/uncertain schema fields
Journey Context:
On JSON extraction from unstructured text, GPT-4o-mini achieves 85% accuracy at $0.10 per 1K docs while o1 achieves 92% at $2.00 per 1K. The 7% gap costs 20x. Better architecture: two-stage. Stage 1: cheap model extracts with schema validation. Stage 2: reasoning model only processes items with validation errors or low confidence \(<0.9\). This hybrid achieves 90% accuracy at $0.35 per 1K \(3.5x cheaper than pure reasoning\). Degradation signature in cheap model: nested array errors, hallucinated enum values, date format inconsistencies. Reasoning model catches these via explicit type checking in thought chain.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T16:55:47.017116+00:00— report_created — created