MCP Csharp
atherio-danp/cde-dotnetcc
Create, debug, test, and publish MCP (Model Context Protocol) servers in C using the official ModelContextProtocol SDK — tools/prompts/resources, stdio vs HTTP transport, MapMcp hosting.
A skill your agent uses when building Model Context Protocol (MCP) servers in .NET, configuring tools, transports (SSE/stdio), JSON serialization for AOT, or testing MCP endpoints
Install Creating Dotnet MCP Servers
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-servers --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .claude/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .claude/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-serversType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-servers --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .agents/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .agents/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-servers --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .cursor/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .cursor/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/SebastienDegodez/copilot-instructions.git --path skills/creating-dotnet-mcp-servers--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-servers --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .gemini/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .gemini/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-serversInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .github/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .github/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install SebastienDegodez/copilot-instructions creating-dotnet-mcp-servers --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/SebastienDegodez/copilot-instructions.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/creating-dotnet-mcp-servers .opencode/skills/creating-dotnet-mcp-servers && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "creating-dotnet-mcp-servers" agent skill from https://github.com/SebastienDegodez/copilot-instructions/tree/main/skills/creating-dotnet-mcp-servers into .opencode/skills/creating-dotnet-mcp-servers/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "creating-dotnet-mcp-servers", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
creating-dotnet-mcp-servers- GitHub stars
- 198
- Token cost
- ~1.3k tokens
- SKILL.md length
- 272 words
- Files
- 4 (incl. references)
- Skills in repo
- 19
- Repo updated
- First seen
- Licence
- Apache-2.0
At a glance
A skill your agent uses when building Model Context Protocol (MCP) servers in .NET, configuring tools, transports (SSE/stdio), JSON serialization for AOT, or testing MCP endpoints
- Works in 2 steps: Install Packages → Enable AOT
- Building Model Context Protocol (MCP) servers in .NET
- SKILL.md covers When to Use, Quick Reference, Basic Setup and Tool Implementation, plus 4 more sections
- Calls dotnet
What it does
Creating Dotnet MCP Servers is an agent skill from SebastienDegodez/copilot-instructions. Use when building Model Context Protocol (MCP) servers in .NET, configuring tools, transports (SSE/stdio), JSON serialization for AOT, or testing MCP endpoints
Its SKILL.md is about 1.3k tokens, which your agent loads only when the skill is triggered. The skill folder holds 4 other files, including reference files (for example `references/advanced.md`, `references/error-handling.md` and `references/testing.md`).
It sits in Agent Workflows, covering MCP servers. It works with Model Context Protocol and .NET. The repository describes itself as: A comprehensive codebase of best practices, coding rules, and workflow automation for AI-assisted development with GitHub Copilot. Includes DDD, Clean Architecture, testing… The licence is Apache-2.0.
When your agent uses it
- Building Model Context Protocol (MCP) servers in .NET
- Configuring tools
- Transports (SSE/stdio)
- JSON serialization for AOT
Example prompts
- “/creating-dotnet-mcp-servers”
Workflow steps
2 steps, taken from the step headings in SKILL.md.
What it can do on your machine
Read from SKILL.md and the folder at commit 0f0dccf. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
dotnet
From the folder's file list and the shell code blocks in SKILL.md.
Network
Links to these hosts (documentation or services it may open):
modelcontextprotocol.ionuget.org
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Creating Dotnet MCP Servers loads about 1.3k tokens when it runs, and up to ~11k if it reads all its reference files. Until then it costs about 47 tokens; SKILL.md has 272 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from SebastienDegodez/copilot-instructions at commit 0f0dccf, republished under its Apache-2.0 licence (© SebastienDegodez). 272 words, ~1,256 tokens.
Download SKILL.mdSave it as
.claude/skills/creating-dotnet-mcp-servers/SKILL.md (or your agent's skills folder). This skill also uses 3 other files; get the full folder from GitHub.- name
- creating-dotnet-mcp-servers
- description
- Use when building Model Context Protocol (MCP) servers in .NET, configuring tools, transports (SSE/stdio), JSON serialization for AOT, or testing MCP endpoints
Creating .NET MCP Servers
Build production-ready Model Context Protocol (MCP) servers in .NET with AOT compatibility.
Core principle: MCP servers expose tools via standardized protocol using attribute-based registration and explicit JSON serialization contexts for AOT.
When to Use
graph TD
A[Need to build server?] -->|Yes| B[Using .NET?]
B -->|Yes| C[MCP Protocol?]
C -->|Yes| D[✅ Use this skill]
C -->|No| E[❌ Use REST/gRPC guide]
B -->|No| F[❌ See Python/TS MCP docs]
A -->|No| G[❌ Skip]Use this skill when:
- Building new MCP server in .NET
- Configuring SSE or stdio transport
- Enabling AOT compilation
- Need testing or error handling patterns
Not for: Non-.NET MCP, client-side integration, generic APIs
Quick Reference
| Task | Implementation |
|---|---|
| Install packages | dotnet add package ModelContextProtocol + ModelContextProtocol.AspNetCore |
| Mark tool class | [McpServerToolType] |
| Mark tool method | [McpServerTool(Name = "ToolName"), Description("...")] |
| Parameter description | [Description("param description")] string param |
| Register server | services.AddMcpServer().WithHttpTransport().WithTools<T>() |
| Map endpoints | app.MapMcp() (exposes /sse) |
| AOT serialization | Create JsonSerializerContext with [JsonSerializable] |
| Test transport | Use SseClientTransport + McpClientFactory |
Basic Setup
1. Install Packages
dotnet add package ModelContextProtocol --version 0.3.0-preview.1
dotnet add package ModelContextProtocol.AspNetCore --version 0.3.0-preview.1
# For testing (optional)
dotnet add package ModelContextProtocol.Client --version 0.3.0-preview.12. Enable AOT
Project configuration:
<PropertyGroup>
<PublishAot>true</PublishAot>
<JsonSerializerIsReflectionEnabledByDefault>false</JsonSerializerIsReflectionEnabledByDefault>
</PropertyGroup>JSON serialization context:
[JsonSerializable(typeof(PackageMetadata))]
[JsonSerializable(typeof(IEnumerable<PackageMetadata>))]
public partial class McpJsonContext : JsonSerializerContext { }Register in Program.cs:
builder.Services.AddMcpServer()
.WithTools<PackageTools>(serializerOptions: McpJsonContext.Default.Options);Critical: Add ALL tool return types to [JsonSerializable] attributes.
Tool Implementation
Minimal example:
[McpServerToolType]
public sealed class PackageTools
{
public const string SearchPackages = "SearchPackages";
[McpServerTool(Name = SearchPackages)]
[Description("Search for NuGet packages by name or keyword")]
public async Task<IEnumerable<PackageMetadata>> SearchAsync(
[Description("The package name or search keyword")] string query,
[Description("Maximum number of results (default: 10)")] int limit = 10,
CancellationToken cancellationToken = default)
{
// Implementation
}
}Key patterns: Sealed classes, const tool names, [Description] on method and parameters, always accept CancellationToken.
Transport Configuration
SSE (HTTP):
builder.Logging.AddConsole(options => options.LogToStandardErrorThreshold = LogLevel.Trace);
builder.Services.AddMcpServer().WithHttpTransport().WithTools<PackageTools>(...);
app.MapMcp(); // Exposes /sseStdio (CLI):
builder.Services.AddMcpServer().WithStdioTransport().WithTools<PackageTools>(...);
// No MapMcp() neededTesting and Error Handling
📖 See references:
- Testing MCP servers - Integration tests, fixtures, Testcontainers
- Error handling patterns - Structured errors, error codes, logging
Common Mistakes
| Mistake | Fix |
|---|---|
Forgot [JsonSerializable] for return type | Add all tool return types to JsonSerializerContext |
| Not logging to stderr | Set LogToStandardErrorThreshold = LogLevel.Trace |
Missing CancellationToken | Always add CancellationToken parameter |
| Throwing exceptions in tools | Return ToolResult<T> with structured errors |
| Magic strings for tool names | Use const string in tool class |
No [Description] on parameters | Add [Description] to all parameters |
Forgetting MapMcp() | Required for HTTP/SSE transport |
References
- 📖 Testing - WebApplicationFactory, fixtures, Testcontainers
- 📖 Error Handling - Structured errors, error codes
- 📖 Advanced Topics - Clean Architecture, deployment, monitoring
- MCP Specification
- ModelContextProtocol NuGet
© SebastienDegodez, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
SKILL.md and 3 other files (references) in skills/creating-dotnet-mcp-servers of SebastienDegodez/copilot-instructions.
- SKILL.md
- references/advanced.md
- references/error-handling.md
- references/testing.md
Open the folder on GitHubat commit 0f0dccf
Compare with similar skills
Creating Dotnet MCP Servers next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Creating Dotnet MCP Servers this skillSebastienDegodez/copilot-instructions | 198 | — | ~1.3k | Automated safety check: Pass | Apache-2.0 | |
| MCP Csharpatherio-danp/cde-dotnetcc | 109 | — | ~1.2k | Automated safety check: Notes | None | |
| Csharp MCP Server GeneratorILoveDotNet/ilovedotnet | 155 | — | ~560 | Automated safety check: Pass | CC0-1.0 | |
| Dotnet MCP Builderboshi-xixixi/TraeSkill | 276 | — | ~1.7k | Automated safety check: Pass | MIT | |
| Dotnet MCP Buildergithub/awesome-copilot | 40k | — | ~2.1k | Automated safety check: Pass | MIT | |
| Microsoft Docsmicrosoft/ai-agents-for-beginners | 77k | — | ~1.5k | Automated safety check: Pass | MIT |
Similar skills
Csharp MCP Server Generator
ILoveDotNet/ilovedotnet
Generate a complete MCP server project in C with tools, prompts, and proper configuration
Dotnet MCP Builder
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Build Model Context Protocol (MCP) servers in C/.NET against the current ModelContextProtocol 1.x NuGet packages.
- Official
Dotnet MCP Builder
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Build Model Context Protocol (MCP) servers in C/.NET against the current ModelContextProtocol 2.x NuGet packages.
- Official
Microsoft Docs
microsoft/ai-agents-for-beginners
Küsib ametlikku Microsofti dokumentatsiooni, et leida mõisteid, juhendeid ja koodinäiteid Azure'i, .NET-i, Agent Frameworki, Aspire'i, VS Code'i, GitHubi ja muu kohta.
Copilot SDK
intellectronica/agent-skills
This skill helps with GitHub Copilot SDK work across Node.js/TypeScript, Python, Go, .NET, and Java.
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Related
Works with
Categories
Questions about Creating Dotnet MCP Servers
What does Creating Dotnet MCP Servers do?
A skill your agent uses when building Model Context Protocol (MCP) servers in .NET, configuring tools, transports (SSE/stdio), JSON serialization for AOT, or testing MCP endpoints. Creating Dotnet MCP Servers is an agent skill from SebastienDegodez/copilot-instructions.
When should I use Creating Dotnet MCP Servers?
Creating Dotnet MCP Servers fits situations like: building Model Context Protocol (MCP) servers in .NET; configuring tools; transports (SSE/stdio); JSON serialization for AOT.
How do I install Creating Dotnet MCP Servers in Claude Code?
Run `npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a claude-code`. Or copy the skill folder (skills/creating-dotnet-mcp-servers in SebastienDegodez/copilot-instructions) into .claude/skills/creating-dotnet-mcp-servers in your project. Claude Code loads it when a task matches its description.
How do I install Creating Dotnet MCP Servers in Codex?
Run `npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a codex`. Or copy the skill folder (skills/creating-dotnet-mcp-servers in SebastienDegodez/copilot-instructions) into .agents/skills/creating-dotnet-mcp-servers in your project. Codex loads it when a task matches its description.
Can I use Creating Dotnet MCP Servers in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add SebastienDegodez/copilot-instructions --skill creating-dotnet-mcp-servers -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/creating-dotnet-mcp-servers, .gemini/skills/creating-dotnet-mcp-servers, .github/skills/creating-dotnet-mcp-servers and .opencode/skills/creating-dotnet-mcp-servers in your project.
What does Creating Dotnet MCP Servers need to run?
Going by SKILL.md and its folder, Creating Dotnet MCP Servers needs the command-line tools its instructions call (dotnet).
Does Creating Dotnet MCP Servers access the network?
SKILL.md names 2 domains. As links in the text: modelcontextprotocol.io and nuget.org. This is read from the text; nothing was executed.
Is Creating Dotnet MCP Servers safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Creating Dotnet MCP Servers use?
Creating Dotnet MCP Servers is published under the Apache-2.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Creating Dotnet MCP Servers use?
About 1.3k tokens (SKILL.md is roughly 5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 9.6k tokens, read only when the agent opens those files.
What are the alternatives to Creating Dotnet MCP Servers?
Skills that share tags, products or a category with Creating Dotnet MCP Servers: MCP Csharp (atherio-danp/cde-dotnetcc, 109 stars), Csharp MCP Server Generator (ILoveDotNet/ilovedotnet, 155 stars), Dotnet MCP Builder (boshi-xixixi/TraeSkill, 276 stars) and Dotnet MCP Builder (github/awesome-copilot, 40k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Creating Dotnet MCP Servers?
SebastienDegodez (a GitHub user) maintains it in SebastienDegodez/copilot-instructions, which has 198 GitHub stars. The repository holds 19 skills in this directory. The repository was last updated on October 6, 2026.
Source: SebastienDegodez/copilot-instructions on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.