Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/managedcode/dotnet-skills/semantic-kernelnpx skills add managedcode/dotnet-skills --skill semantic-kernelgit clone --depth 1 https://github.com/managedcode/dotnet-skillsWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00116 | $0.02330 |
| Opus 5 | $0.00058 | $0.01165 |
| Sonnet 5 | $0.00023 | $0.00466 |
| Haiku 4.5 | $0.00012 | $0.00233 |
Grade A, and why
semantic-kernel scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 290 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Semantic Kernel for .NET
Trigger On
- adding AI-driven prompts, plugins, or orchestration to a .NET app
- reviewing kernel construction, service registration, or plugin usage
- building function-calling patterns with LLMs
- migrating older Semantic Kernel code to current APIs
Documentation
- Semantic Kernel Overview
- Plugins and Functions
- Agent Functions
- GitHub Repository
- Semantic Kernel .NET 1.80.0 release
- Microsoft Agent Framework
References
- patterns.md - Plugin patterns, function calling patterns, multi-agent patterns, prompt templates, and RAG patterns
- anti-patterns.md - Common Semantic Kernel mistakes and how to avoid them
Core Concepts
| Concept | Description |
|---|---|
| Kernel | Central orchestrator for AI services and plugins |
| Plugin | Collection of functions exposed to the LLM |
| Function | Native C# method or prompt template |
| Chat Completion | LLM service for generating responses |
| Memory | Vector storage for semantic search |
Workflow
- Build the Kernel with required services
- Create Plugins with well-described functions
- Configure Function Calling for automatic tool use
- Handle Responses and manage conversation state
- Test and Observe AI behavior with logging
- For Semantic Kernel
dotnet-1.79.0and later, keep OpenAPI plugin server URL validation enabled, do not re-enable automatic redirects on the defaultHttpPluginorWebFileDownloadPluginclients without an explicit trusted-host policy, and use the current Microsoft Agent Framework-compatible migration samples when moving SK agent code to Agent Framework. - Re-test Cosmos DB vector-store queries, file and document plugins, OpenAPI server-variable URLs, and Ollama reasoning settings after upgrading to
1.79.0. The release fixes the Cosmos vector-store path, rejects mixed-separator UNC paths, URL-encodes OpenAPI server variables, adds OllamaThink, and allows deterministicTimePlugintests throughTimeProviderinjection. - Treat the Prompty.Core
2.0.0-beta.3update in1.79.0as a breaking dependency change. Re-run prompt-template tests and remove security workarounds that are no longer needed after the vulnerable transitive version is gone. - In
1.80.0, re-test OpenAPI plugin HTTP-client defaults and Gemini calls that restrictFunctionChoiceBehaviorto a supplied function list. The migrated .NET MEVD providers are no longer owned by Semantic Kernel; follow their redirect guidance and keep vector-provider package references explicit during upgrades.
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 290 lines · 116 tokens per session scan A 9b6da01afa5a
semantic-kernel is a skill published in the GitHub repository managedcode/dotnet-skills (477 stars, last pushed 2d ago), licensed MIT. It adds 116 tokens to every session and 2,330 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
winui-ui-testing
Automated UI testing for Windows desktop apps — generate a batch test script with the winapp ui UI Automation harness, run all tests in one pass, read results. Covers element assertions, interactions, value checking (TextBox, ComboBox, ToggleSwitch), keyboard shortcuts and typing (send-keys), hover, drag-and-drop…
pr-review
Multi-dimensional review of a PR or feature branch in microsoft/win-dev-skills. Activate on "review my PR / changes / branch", "vet before pushing", "PR review", "is this ready to merge". Fans out parallel sub-agents over skill content, the skill-vs-tool boundary (solution hierarchy), tool correctness…
winui-design
Use when designing, reviewing, or fixing WinUI 3: sample and control discovery with winapp find-ui, layout planning, control choice, Fluent Design alignment, Light/Dark/High Contrast theming, typography, spacing, brushes, accessibility, and XAML data-binding design. Load before authoring new XAML, reviewing UI PRs…
winui-dev-workflow
Build and run workflow for WinUI 3 apps with WinApp CLI 0.6+ — project creation with winapp new, project-mode winapp run, BuildAndRun.ps1 analyzer integration, crash diagnosis, and prerequisites. Use when creating, building, running, or fixing build errors in a WinUI 3 project.
winui-packaging
MSIX packaging, code signing, and distribution for WinUI 3 apps — build for release, certificate generation (winapp cert generate), certificate trust, code signing (winapp sign), self-contained deployment, CI/CD with GitHub Actions, and Microsoft Store submission. Use when preparing for release, creating MSIX…
winui-session-report
Analyze the current or a recent agent session (GitHub Copilot CLI or Claude Code) and generate a diagnostic report. Use only when the user explicitly asks for session feedback, agent debugging, or a review of what happened during a build session. Do not inspect session data automatically.