So I think you should give a try in our AIBot feature in the DiscourseAI plugin. Start with our “Forum Helper” persona, it’s almost perfect fit for your use case.
After that, you can go and New AI Persona Editor for Discourse to create a persona specialized on your needs. Give it both search and read capabilities and write a good system prompt and you are off to the races.
I gave your access to the feature here on Meta, refresh your browser to see and play with it.