Agent Framework builder skills for .NET and Python coding agents

Microsoft added installable builder skills for the Agent Framework in .NET and Python, giving coding assistants Microsoft-maintained guidance on choosing a pattern and wiring tools, sessions, workflows and hosting. They are development-time skills, installed with GitHub CLI or the skills CLI, and the .NET one covers AIAgent, Microsoft.Extensions.AI, dependency injection and ASP.NET Core hosting.

Key points

• Microsoft ships agent-framework-builder-dotnet and agent-framework-builder-python skills for the Agent Skills format.
• Install with `gh skill install microsoft/agent-framework agent-framework-builder-dotnet@main` or `npx skills add`.
• Each skill has a SKILL.md entry point plus references loaded only as the task requires.
• Guidance recommends the smallest pattern: single agent, harness, or workflow with checkpointing.
• The .NET skill covers AIAgent, Microsoft.Extensions.AI, NuGet packages, dependency injection and ASP.NET Core hosting.
• Pair it with the Microsoft Learn MCP Server to search full Agent Framework docs and code samples.

Microsoft published installable builder skills for the Agent Framework in .NET and Python, giving coding assistants Microsoft-maintained guidance when they build or change agent apps. These are development-time assets for your assistant, not runtime skills your shipped application loads. Install with `gh skill install microsoft/agent-framework agent-framework-builder-dotnet@main` or the cross-agent skills CLI via `npx skills add`.

Each skill has a SKILL.md entry point plus focused references, and the agent loads only what the task needs. Guidance favours the smallest workable pattern: one agent for tools and sessions, a harness for an operating loop, a workflow when routing and checkpointing are required. The .NET skill covers AIAgent, Microsoft.Extensions.AI, NuGet packages, dependency injection and ASP.NET Core hosting; pair it with the Microsoft Learn MCP Server for full docs and samples.

Real-world use

• A team standardising how its coding assistant scaffolds new Agent Framework agents in an ASP.NET Core service.
• A developer turning an existing single research agent into a review workflow with checkpointing and resume tests.
• A support assistant with several tools where the agent should stay single-agent instead of becoming a multi-agent system.
• An Azure-hosted agent project that needs Foundry model and deployment guidance alongside the builder skill.

Why it matters

Agent scaffolding is where coding assistants most often invent APIs or over-engineer with multi-agent designs; Microsoft-maintained skills keep the generated code aligned with current Agent Framework patterns and packages.

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