The biggest risk in an internal chatbot is not that it knows too little. It is that it sounds confident without evidence.
Limit the source scope
Start with one department, process or product line. Focused sources are easier to test and maintain.
Require citations
Important answers should show the document and version they came from. Uncited answers should be treated as drafts.
Design refusal
If the knowledge base does not contain the answer, the bot should say so and route the question to a human.
Turn feedback into updates
Collect why an answer was wrong: outdated source, misunderstood question, missing context or changed process.