AI guardrails that stop made‑up answers before your customers see them
AI guardrails in Hay.chat check every answer that states a fact before your customer sees it. Anything your documents can't back up goes to your team instead.
What happens when the AI isn't sure?
It doesn't get to guess. An answer that states a fact goes through up to three checks before it's sent. Fail one and it gets one retry, then it's escalated to your team.
- Stage 0 Did it claim something it didn't do? A reply that says "I've refunded you" is checked against the tools that ran this turn. A failed call doesn't count. If it fails: one more try, then your team.
- Stage 1 Did it invent a product or a policy? Blocks made-up products and policies, competitor suggestions and off-topic answers. Critical violations are always blocked. If it fails: one more try, then your team.
- Stage 2 Can your documents back it up? Scored on grounding (60%), retrieval quality (30%) and the model's own certainty (10%). 0.8 and up: sent. 0.5 to 0.79: rechecked with more documents. Below 0.5: your team.
The exact numbers are in our technical guardrails documentation.
Can it get things wrong?

Does the AI lie to customers?
A language model can state something untrue and sound completely sure of it. When a check catches a bad answer, the customer gets a short message that acknowledges what they asked, in their language, and a hand-off to your team. That message is written without seeing the blocked reply, so the bad claim can't sneak back in.

How often is it wrong?
We don't publish an accuracy rate, because there isn't an honest one that would mean anything for your store. It depends on your documents. Every checked reply carries its confidence score and the documents it used, so you can measure your own. Expect more hand-offs in the first weeks, while your documents have gaps. The safe AI guide has the week-by-week picture.

Can it make up a policy, like the Air Canada chatbot did?
That's what Stages 1 and 2 are for. In 2024 a tribunal held Air Canada to a refund rule its chatbot had made up (Moffatt v. Air Canada). In Hay.chat, a policy your documents don't contain is flagged, retried once, then escalated. Even one that sounds right, like "apply within 90 days", scores low if your page says otherwise. More in what works and what fails with AI chatbots.
What you control

Is it safe to let it act?
Safe enough if you set the limits. Actions follow your playbook rules, so a refund cap is a line in a refund playbook: over the cap, it goes to your team. Stage 0 catches any reply that claims an action that didn't run. Approval mode holds replies, not actions. More on the human approval page.

Who can see what it decided?
Your team can, conversation by conversation. Each time Stage 1 or 2 runs, the log records whether it passed, what it found, the reviewer's reasoning, the score and the documents used, plus the original text of any reply that was replaced. Developers can read all of it through the API.

Can I change the thresholds?
Yes, for the fact check. Settings, then General, has the high and medium thresholds (0.8 and 0.5 by default), the recheck, the escalation switch and the fallback message. Raise the thresholds and more answers go to your team. We'd leave escalation on, because with it off a low-scoring answer is sent as written.
How do other AI support tools handle made-up answers?
All four check answers against your content in some form, so the difference is in what they publish. Only one says it checks that a claimed action really happened.
Swipe the table sideways to see every column.
| Tool | Checks the answer against your content | Checks a claimed action really ran | When it isn't sure | Decision log | Published hallucination rate |
|---|---|---|---|---|---|
| Hay.chat | Yes. Stage 2 scores each company claim against your documents, tool results and playbook | Yes. Stage 0 compares claimed actions with the tools that actually ran | Rechecks once with more documents, then escalates to your team | Yes, per conversation, for Stages 1 and 2 | None published |
| Fin | Yes. A validation step checks the answer is grounded in your knowledge and support content | Not stated | Asks the customer to clarify, or says it can't answer and escalates to your team | Not stated | None. Claims "industry-low hallucinations" without a figure |
| Zendesk AI agents | Says every generated answer is supported by your approved knowledge sources. No separate check described | Not stated | Falls back and hands off to a human agent | Not stated | None published |
| Ada | Yes. A final check against your approved knowledge sources. Non-compliant answers are blocked | Not stated | Asks clarifying questions, or hands off to a human agent | Yes. Every conversation is monitored and logged | None published |
As of 21 October 2026, from each vendor's own pages: The Fin AI Engine (updated 6 March 2026), Zendesk's reliability architecture article (28 April 2026), and Ada's agent logic docs and trust page. "Not stated" means we couldn't find it there. Pricing, sources shown to customers and EU hosting are compared in the safe AI guide.
What do the standards say an AI agent should have?
US · NIST
The Generative AI Profile (NIST AI 600-1, July 2024) calls it confabulation: "confidently stated but erroneous or false content". Stages 1 and 2 are aimed at exactly that.
OWASP
Excessive Agency (LLM06:2025) asks for least privilege and "human-in-the-loop control to require a human to approve high-impact actions". In Hay.chat that's your playbook rules, with Stage 0 checking the claims.
UK · ICO and NCSC
The ICO's guidance on accuracy wants wrong outputs caught and fixed, and the NCSC's secure AI guidelines ask for logging. That's the hand-offs and the guardrail log.
EU · EDPB
The LLM privacy risks report written for the EDPB (April 2025) suggests post-processing filters to catch inaccurate output. Stages 1 and 2 are post-processing filters.
Find out what your documents can and can't back
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Frequently asked questions
Written by Damien Mulhall. Last reviewed against Hay.chat's guardrails documentation. See also security, how documents work and pricing.