how limit amazon bedrock to answer only a limited set of questions?

Hi,

If possible for you, the right way to achieve what you want is to use a Knowledge Base for Amazon Bedrock and the service will then limit the answer of the LLM to the strict content of the RAG Knowledge Base via proper prompt engineering.

See all details of this mechanism in my article: https://repost.aws/articles/AR-LV1HoR_S0m-qy89wXwHmw/the-leverage-of-llm-system-prompt-by-knowledge-bases-for-bedrock-in-rag-workflows

Best,

Didier