I’m trying to choose an approach for building an internal company chatbot using OpenAI and Microsoft stack. I am surprised that it’s hard to find a clear comparison of available options in Azure world for such a popular topic nor a reference architecture.
My key requirements are:

• Possibility to use OpenAI services for natural language conversation
• Possibility to use custom, internal data sources (pdfs, websites, ..) as knowledge base for the bot Support for various channels e.g. website, teams, messenger
• Support for various channels e.g. website, teams, messenger

When I search for implementation options I can see various options, but no real comparison. Options I have identified so far:

• Boilerplate code from Azure samples – ready code on github, for creating all services and web app with chat UI. Not sure what is required to implement different channels
• Chat implementation using Power Virtual Agents – not sure about the pricing, currently it redirects to Copilot page (unclear)
• “Bot services” under Azure AI Services – what are those?
• “Azure Bot” in Azure Marketplace, published by MS. Again, not sure what is that

This all seems quite confusing. Can you please provide comparison of options above or provide better alternatives?