Microsoft Agent Framework python-1.19.0: vector-store protocols and breaking MCP / A2A / AG-UI client changes

The Python packages of Microsoft Agent Framework reached 1.19.0 on 2026-09-18. The changelog lists generic vector-store provider protocols with new MongoDB, Azure DocumentDB and Azure Cosmos DB connectors, stable names for built-in orchestration workflows with checkpoint types registered for restoration, and an option to invoke function calls sequentially. Changes marked breaking: HTTP cookie persistence is now explicit in the agent-framework-a2a, agent-framework-ag-ui, core and declarative packages; MCP skill archives are limited to ZIP files and the MCP sampling callback is deprecated; provider-backed MCP sessions in the declarative package are scoped per invocation. Source: python-1.19.0 release notes.

Relation to the directory: see Microsoft Agent Framework, Microsoft Agent Framework vs AutoGen and the protocol matrix.