🟢 Just shippedGA 2026-08-22
Microsoft Agent Framework .NET 1.19.0
Adds session-persisted chat client routing, Azure Blob Storage session persistence and persistence of hosted agent state in Foundry, plus support for resilient long-running and steerable Foundry hosted agents and an agent-hooks interception contract as a first-class experimental feature. Breaking change: MCP long-running task support migrates to the 2026-07-28 Tasks extension, and snake_case argument names in tool descriptions are fixed.
Why it matters: Teams running .NET agents against Foundry hosted agents should plan the MCP Tasks extension migration before upgrading, since the long-running task contract changes.
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