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Knowledge checks

Check every AI reply against your own facts.

A knowledge check compares an AI reply with the facts you saved (your refund window, shipping rules, prices, hours, approved links). If the reply contradicts a fact, the check blocks it and tells you which fact it conflicts with and where that fact came from.

1. Add your facts

Open Facts in the dashboard. You can:

We split the text into short fact statements. Each one keeps a reference to where it came from (a heading and paragraph, or a PDF page). You can edit or delete any fact. How many own documents your plan allows is on the Pricing page; fact packs do not count as documents.

2. Turn the facts check on

Add "check_facts": true to the request body of POST /v1/validate, or put "check_facts": true inside a rule set (the rule sets made by fact packs and Guided setup already have it).

curl -X POST https://nexxtool.ai/v1/validate \
  -H "Authorization: Bearer wtk_live_..." \
  -H "Content-Type: application/json" \
  -d '{"output":"You have 60 days to return any item.",
       "contract":{"type":"text"}, "check_facts": true}'
{
  "pass": false,
  "issues": ["Contradicts: 'Returns accepted within 30 days of delivery.' — Returns policy"],
  "knowledge": {
    "checked": true, "ai": "none",
    "contradictions": [{
      "fact": "Returns accepted within 30 days of delivery.",
      "source": "Returns policy", "ref": "Returns, paragraph 1",
      "quote": "You have 60 days to return any item.",
      "reason": "The reply says 60 days but this fact says 30 days.", "how": "compare"
    }]
  }
}

No contradiction means the check passes. A knowledge check counts as one normal check, the same as any other call.

How it decides

  1. Comparison (instant, no AI). Numbers, money, percentages and time spans in the reply are compared with the facts about the same topic (returns, shipping, discounts, prices, hours). "60 days" against "within 30 days", or "free shipping on all orders" against "free shipping on orders over $75", is caught here. If you saved approved links, a link to any other website is flagged.
  2. AI judge. If the comparison finds nothing, the facts that share words with the reply are sent to an AI model, which must answer with the fact number, a quote and a reason, or "no contradiction". Your own AI key is used when you saved one (Bring your own AI), otherwise our model. If the AI cannot be reached or its answer cannot be read, you get an error and the reply is not passed; that check is not charged.

Limits and honesty