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Stop prompt injection from hijacking your agent, new security capabilities now released within Agent Framework

Prompt injection is the #1 risk on the OWASP LLM Top 10, and most agents in production today defend against it with one of two heuristics: a defensive system prompt, or a hand-rolled allowlist. Neither is deterministic. Both fail silently the day someone slips a [SYSTEM OVERRIDE] line...
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Announcing Agent Governance Toolkit MCP Extensions for .NET

Announcing a Public Preview .NET package that adds policy enforcement, startup tool scanning, fallback governance, and response sanitization to MCP servers with a single builder extension.
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Latest posts

May 20, 2026
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The classic TreeView control lets me sort by name or by lParam, but why not both?

Raymond Chen
You need to arrange to get one from the other.
The Old New Thing
May 19, 2026
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Introducing Sample Profile Guided Optimization in MSVC

David Gillies
Profile Guided Optimization (PGO) has long been one of the most powerful tools in the MSVC compiler's arsenal for improving the runtime performance of C and C++ applications. By using execution profile data collected from representative workloads, PGO enables the compiler to make smarter...
C++ Team Blog
May 19, 2026
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How to run evals for the model router

Sanjeev,
leestott,
Marie-Louise
Walk through running quality, cost, and latency evaluations for the Foundry model router using an open-source GitHub repo designed for router-aware eval pipelines.
Microsoft Foundry Blog
May 19, 2026
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Package Identity

Howard Kapustein
An MSIX package identity is composed of a five-part tuple that uniquely identifies a package. It consists of the following attributes: Name Version Architecture Resource Id Publisher Together, these fields form the canonical identity of a package. Programmatically, this identity can...
Inside MSIX
May 19, 2026
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Agentic-Agile: Why Agent Development Needs Agile (Not Just Prompts)

Daniel Epstein
"A bad system will beat a good person [or agent] every time" ~Dr. William Edwards Deming (with apologies) I started vibe coding by writing prompts (often dictated into my phone), refining them with an agent in M365 Copilot, and creating handoff files to use with GitHub Copilot CLI. The...
Microsoft for Developers
May 19, 2026
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Eliminate LLM Cold starts: Load models up to 6x Faster with Azure Blob Storage and Run:AI Model Streamer

Vishnu Charan TJ
Stop paying for idle GPUs while model weights copy to disk. Stream them straight into GPU memory instead with Run:AI Streamer from Azure Blob Storage. The Problem: Every Cold Start Costs You More Than Money GPU compute is among the most expensive cloud infrastructure, and every...
Azure SDK Blog
May 19, 2026
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What is the history of the ERROR_ARENA_TRASHED error code?

Raymond Chen
The storage control blocks were destroyed.
The Old New Thing
May 19, 2026
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NuGet PackageReference for C++ Projects in Visual Studio

Augustin Popa
Native C++ projects (.vcxproj) now support NuGet PackageReference, the same modern package management experience .NET developers have used for years. Available as an experimental feature in Visual Studio 2026 version 18.7.
C++ Team Blog
May 18, 2026
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NuGet Package Pruning: Cleaner Dependencies and Actionable Vulnerability Reports

Nikolche Kolev
Package pruning in .NET 10 removes platform-provided packages from your dependency graph. With transitive auditing enabled by default, projects with these defaults have 70% fewer transitive vulnerability reports compared to projects using the previous defaults.
.NET Blog