Every form submission, in the person's own words, with where they came from. Label each one so tests are judged on good leads, not just more leads.
“Second quote for window replacement. The first one came in high and I want to compare.”
“Do you sell the parts? I want to do it myself.”
The AI labels every lead. “Needs review” means it was unsure, so a person decides; anyone can change any label. The AI reads the answers only, never names, emails or phone numbers.