Microsoft 365 Agent Builder natively supports using Microsoft Teams data—including channels, group chats, and 1:1 chats—as a direct knowledge source to ground an agent. However, past Microsoft 365 Copilot interaction transcripts are not an officially supported data source; grounding is restricted to enterprise sources like SharePoint, Dataverse, web URLs, Graph Connectors, and Teams. Furthermore, image files such as JPG or PNG cannot be used. Copilot specifically parses text content for knowledge retrieval, explicitly restricting supported file uploads to standard document formats such as .docx, .pdf, .pptx, .xlsx, and .txt.

Microsoft Learn, Add knowledge sources to your declarative agent in Microsoft 365 Copilot (Article: microsoft-365-copilot/extensibility/agent-builder-add-knowledge), Section: "Microsoft Teams data".

Microsoft Learn, Agent Registry in the Microsoft 365 admin center (Article: microsoft-365/admin/manage/agent-registry), Section: "Supported file types and limits" (Confirming the exclusion of image formats).

Microsoft Learn, Knowledge sources summary - Microsoft Copilot Studio (Article: microsoft-copilot-studio/knowledge-copilot-studio), Section: "Supported knowledge sources" (Confirming the exclusion of Copilot conversations).