Calling the AI bluff: Adding "Do not guess" cut made-up fields from 71% to 20%

Adding the instruction "Do not guess" to web extraction prompts reduced AI-generated hallucinations from 70.7% to 20.2% across 16 models. Buyer agents can further verify these results by using low-cost models like GPT-6 Luna or Jev to cross-reference returned values against source pages for a fraction of a cent per request.