Knowledge & RAGIntermediate7 min read

How to Prevent AI Chatbot Hallucinations with Custom Knowledge and Q&A Overrides

Learn how SiteMind’s strict cosine similarity thresholds, Reciprocal Rank Fusion (RRF), and instant Q&A overrides guarantee 100% grounded, hallucination-free customer support answers.

What you will achieve

  • Configure strict cosine similarity refusal thresholds
  • Add instant Q&A overrides that bypass document re-crawling
  • Turn unanswered customer questions into a prioritized knowledge base roadmap

Prerequisites

  • A SiteMind workspace with at least one indexed knowledge source
01

Understand the Grounding Architecture

Generic LLMs hallucinate because they predict next words from general training data. SiteMind enforces a 2-stage verification pipeline: Reciprocal Rank Fusion (dense pgvector + sparse full-text search) retrieves only high-confidence matches. If cosine similarity falls below your threshold, the assistant politely declines rather than guessing.

02

Similarity & Refusal Thresholds Are Enforced Automatically

There is nothing to configure here. Grounding is enforced automatically on the server: an answer is only written when the retrieved content is similar enough to the question; otherwise the assistant says it couldn’t find the information in your content.

03

Create Instant Custom Q&A Overrides

Need your assistant to answer a specific promotion, coupon policy, or VIP hotline question without editing your live website? Go to Dashboard > Knowledge > Custom Q&A. Create a pair — changes update vector embeddings instantly.

04

Review Knowledge Gaps from Unanswered Queries

Open Dashboard > Conversations > Knowledge Gaps. SiteMind automatically clusters questions the assistant declined to answer, giving your content team an exact list of missing FAQs to write.

Frequently asked questions

Why is declining to answer better than guessing?

In customer support, giving an incorrect return policy or wrong price destroys trust and creates legal liabilities. An honest refusal with a prompt to contact human support preserves trust and pinpoints documentation gaps.

How fast do custom Q&A overrides go live?

Instantly! Embeddings are generated in under 300ms upon clicking Save in the dashboard.

Live in 2 minutes

Ready to put this recipe to work?

Start your 3-day free trial on SiteMind. Connect your website URL, test grounded answers in our interactive playground, and deploy on your site with zero coding.

3-day full-access trialNo credit card required1:1 transparent credits