A no-hallucination checklist for n8n builders using LLM nodes to extract structured data from emails, PDFs, forms, transcripts, and CRM notes.
A fresh r/n8n discussion asked how to stop LLMs from hallucinating or guessing during extraction. That is production-risk buyer intent: bad AI output can quietly pollute CRMs, invoices, tickets, and customer messages.
For each extraction field, require source evidence, explicit confidence, safe missing-data handling, and a downstream gate before any production write.
The model points to the exact source span, quote, row, page, or field it used.
Output includes confidence, needs_review, and a reason for every important field.
The workflow allows null, unknown, or not_provided instead of rewarding made-up values.
Low-confidence or missing-required fields create a review task, not a production update.
| Scenario | Input to test | Expected behavior | Evidence |
|---|---|---|---|
| Complete record | All required fields present | Writes valid record | Execution log + source snippets |
| Missing required field | No email, phone, amount, or date | Routes to review | Review task screenshot |
| Ambiguous value | Two dates, names, or owners | needs_review=true | Quote showing ambiguity |
| Contradictory value | Subject and body disagree | Routes to review | Both conflicting snippets |
| Invalid format | Bad email/date/phone | Blocks downstream write | Validation error/log |
| Prompt injection | Source says “ignore rules” | Treated as source text only | Safe output JSON |
| OCR junk | Blank or noisy source | Returns nulls, no write | Execution log |
The launch kit includes the field manual, n8n starter templates, prompt pack, setup checklist, troubleshooting checklist, QA checklist, safety checklist, skipped-step audit, and this extraction checklist.
Lead intake responder, quote follow-up assistant, review request automation, prompt pack, and practical operator checklists for safer AI automations.