feat(skills): add dotnet-mcp-builder, deprecate csharp-mcp-server-gen…#1645
Open
AClerbois wants to merge 1 commit intogithub:stagedfrom
Open
feat(skills): add dotnet-mcp-builder, deprecate csharp-mcp-server-gen…#1645AClerbois wants to merge 1 commit intogithub:stagedfrom
AClerbois wants to merge 1 commit intogithub:stagedfrom
Conversation
github-actions
Bot
added
new-submission
Contributor
🔍 Skill Validator Results✅ All checks passed
Summary
Full validator output```text Found 2 skill(s) [csharp-mcp-server-generator] 📊 csharp-mcp-server-generator: 401 BPE tokens [chars/4: 444] (detailed ✓), 2 sections, 2 code blocks [dotnet-mcp-builder] 📊 dotnet-mcp-builder: 1,639 BPE tokens [chars/4: 1,721] (detailed ✓), 7 sections, 1 code blocks ✅ All checks passed (2 skill(s)) ``` |
Contributor
There was a problem hiding this comment.
Pull request overview
Adds a new .NET-focused MCP skill (dotnet-mcp-builder) with on-demand reference docs, and deprecates the older csharp-mcp-server-generator skill in favor of the newer guidance. Updates the skills index to expose the new skill and mark the old one as deprecated.
Changes:
- Added
dotnet-mcp-builderskill with a decision tree + “cardinal rules” for .NET MCP server/client work. - Added 13 reference documents covering transports, primitives, advanced features (elicitation/sampling/roots/apps), and testing.
- Deprecated
csharp-mcp-server-generatorand updateddocs/README.skills.mdaccordingly.
Reviewed changes
Copilot reviewed 16 out of 16 changed files in this pull request and generated 4 comments.
Show a summary per file
| File | Description |
|---|---|
| skills/dotnet-mcp-builder/SKILL.md | New skill overview + decision tree and rules for .NET MCP development |
| skills/dotnet-mcp-builder/references/packages.md | Package/TFM guidance for ModelContextProtocol 1.x |
| skills/dotnet-mcp-builder/references/transport-stdio.md | STDIO transport setup + stdout/stderr trap guidance |
| skills/dotnet-mcp-builder/references/transport-http.md | Streamable HTTP transport setup + deployment/auth notes |
| skills/dotnet-mcp-builder/references/tool-primitive.md | Tool authoring patterns, return types, and error guidance |
| skills/dotnet-mcp-builder/references/prompt-primitive.md | Prompt authoring patterns and return types |
| skills/dotnet-mcp-builder/references/resource-primitive.md | Resource authoring patterns, templates, and subscriptions |
| skills/dotnet-mcp-builder/references/elicitation.md | Elicitation form + URL mode guidance and examples |
| skills/dotnet-mcp-builder/references/sampling.md | Sampling guidance and IChatClient adapter pattern |
| skills/dotnet-mcp-builder/references/roots.md | Roots capability usage + caching + path validation pattern |
| skills/dotnet-mcp-builder/references/server-features.md | Smaller server features (completions/logging/progress/filters) |
| skills/dotnet-mcp-builder/references/testing.md | Inspector + in-memory transport testing patterns |
| skills/dotnet-mcp-builder/references/mcp-apps.md | MCP Apps overview + manual implementation pattern for C# |
| skills/dotnet-mcp-builder/references/client.md | .NET client reference for consuming MCP servers |
| skills/csharp-mcp-server-generator/SKILL.md | Replaced prior content with deprecation notice and migration pointer |
| docs/README.skills.md | Added dotnet-mcp-builder entry; marked old skill as deprecated |
…erator Adds a comprehensive skill for building MCP (Model Context Protocol) servers in C#/.NET against the official ModelContextProtocol 1.x NuGet packages. Covers both transports (STDIO, Streamable HTTP — SSE is deprecated) and every primitive in the current MCP spec (2025-11-25): tools, prompts, resources, elicitation (form + URL mode), sampling, roots, completions, logging, and MCP Apps. Includes a thin .NET MCP client reference and testing guidance (MCP Inspector + in-memory transport for unit tests). Steers the model toward the current stable 1.x packages instead of the 0.x previews it tends to pin by default, and enforces the STDIO stdout/stderr trap. Also deprecates the existing csharp-mcp-server-generator skill, which predates ModelContextProtocol 1.0 and only covered a subset of the current spec. Its SKILL.md now redirects users to dotnet-mcp-builder so existing install URLs keep working without surprises.
AClerbois
force-pushed
the
skill/dotnet-mcp-builder
branch
from
687c1df to
aaafd7f
Compare
github-actions
Bot
removed
skill-check-error
aaronpowell
requested changes
May 8, 2026
Contributor
There was a problem hiding this comment.
Just delete it - the new one is obviously an improvement and I'll be honest, we'll probably never remember to remove this one if we just deprecate it 🤣
Comment on lines
+214
to
+215
| - **CSP too tight or too loose.** If your UI loads from a CDN, declare it in `_meta.ui.csp`. Otherwise the iframe sandbox blocks it. | ||
| - **Forgetting the `_meta` on the tool.** Without it, the host treats your tool as a regular text-returning tool. The UI never appears. |
Contributor
There was a problem hiding this comment.
Would it be better to use the .NET types here rather than the _meta properties it serialises down to?
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
What
Adds dotnet-mcp-builder, a skill for building MCP (Model Context Protocol)
servers in C#/.NET against the official
ModelContextProtocol1.x NuGet packages.Why
There's already
csharp-mcp-server-generator, but it's a 60-line high-levelprompt that references the prerelease packages and only covers the STDIO
"hello world" path. This skill is broader and current with the spec:
elicitation (form + URL mode), sampling, roots, completions, logging
Layout
SKILL.md— workflow, decision tree, cardinal rules (~85 lines)references/— 13 topic-specific deep-dive docs loaded only when neededValidation
npm run skill:validate✅npm run build✅ (auto-updateddocs/README.skills.md)stagedper CONTRIBUTING.mdPull Request Checklist
npm startand verified thatREADME.mdis up to date.stagedbranch for this pull request.Description
This pull request deprecates the
csharp-mcp-server-generatorskill in favor of a new, more comprehensivedotnet-mcp-builderskill for building Model Context Protocol (MCP) servers in .NET. It updates documentation to reflect this change, introduces the new skill and its references, and provides guidance for users to transition. The main focus is on steering users to use the up-to-date, feature-complete approach for MCP server and client development in .NET.Skill deprecation and replacement:
Marked the
csharp-mcp-server-generatorskill as deprecated in bothdocs/README.skills.mdand its ownSKILL.md, with clear guidance to usedotnet-mcp-builderinstead. The new description explains thatdotnet-mcp-buildertargets current ModelContextProtocol 1.x packages, covers all MCP primitives and both major transports, and is a strict superset of the old skill. [1] [2]Added a new entry for
dotnet-mcp-builderindocs/README.skills.md, detailing its capabilities and listing relevant reference documents for different MCP server features and scenarios.New skill and reference documentation:
Introduced
skills/dotnet-mcp-builder/SKILL.md, providing comprehensive guidance for building production-quality MCP servers and clients in C#/.NET, including best practices, decision trees for reference material, and troubleshooting tips.Added a detailed reference,
skills/dotnet-mcp-builder/references/client.md, showing how to consume MCP servers from .NET clients, including package setup, transport configuration, tool invocation, and handling advanced server-to-client features.Type of Contribution
By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.