Add lsp config for dotnet.

[jmoseley]

Add lsp server config for dotnet.

[github-actions]

SDK Consistency Review

I've reviewed this PR for cross-SDK consistency.

Summary

✅ No consistency issues found - This PR adds development tooling (LSP configuration) for the .NET SDK and does not modify any SDK client APIs or functionality.

Analysis

The changes add:

1. .github/lsp.json - Centralized LSP server configuration with C# language server setup
2. dotnet/dotnet-tools.json - .NET tool manifest for the csharp-ls language server

This is infrastructure/tooling for development environment support (IDE integration, code intelligence), not SDK client functionality.

Observation

The .github/lsp.json structure supports multiple language servers (it's a "lspServers" object), but currently only includes C#. While TypeScript, Python, and Go already have their native tooling:

• TypeScript: Has tsconfig.json and TypeScript language server support via standard tooling
• Python: Has pyproject.toml with Ruff and type checking configuration
• Go: Has native gopls support through standard Go tooling

If the intent is to centralize LSP configuration for all SDKs in .github/lsp.json, you might consider adding entries for the other languages in a future PR. However, since each language ecosystem already has well-established LSP tooling, this may be unnecessary.

Conclusion

This PR maintains consistency - it's adding optional development tooling that doesn't impact SDK feature parity or public APIs.

AI generated by SDK Consistency Review Agent

[Copilot]

Pull request overview

This PR adds Language Server Protocol (LSP) configuration for the dotnet/C# SDK components of the repository. It configures the csharp-ls language server to provide IDE features like intellisense, go-to-definition, and other language services for C# files.

Changes:

• Added dotnet tools manifest (dotnet/dotnet-tools.json) to declare csharp-ls as a project tool
• Added LSP configuration (.github/lsp.json) to configure how csharp-ls should be invoked for C# files

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
dotnet/dotnet-tools.json	Declares csharp-ls version 0.21.0 as a dotnet local tool for the project
.github/lsp.json	Configures LSP server to use csharp-ls for .cs files with the GitHub.Copilot.SDK.sln solution

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[Copilot]

The solution file path is incorrect. The LSP configuration references "GitHub.Copilot.SDK.sln" but the actual file is located at "dotnet/GitHub.Copilot.SDK.sln". Since the LSP command will likely be executed from the repository root, the path should be "dotnet/GitHub.Copilot.SDK.sln". This affects both the "--solution" argument and the "projectRootFiles" array.

Suggested change

	"args": ["tool", "run", "csharp-ls", "--solution", "GitHub.Copilot.SDK.sln"],
	"fileExtensions": {
	".cs": "csharp"
	},
	"projectRootFiles": ["GitHub.Copilot.SDK.sln"]
	"args": ["tool", "run", "csharp-ls", "--solution", "dotnet/GitHub.Copilot.SDK.sln"],
	"fileExtensions": {
	".cs": "csharp"
	},
	"projectRootFiles": ["dotnet/GitHub.Copilot.SDK.sln"]

[Copilot]

The dotnet-tools.json manifest is missing the required "packageId" field for the csharp-ls tool. The packageId field specifies the NuGet package identifier and is required for dotnet to restore and run the tool correctly. Without this field, the tool installation will fail.

[jmoseley]

Regarding the review comments:

Solution file path: The config uses rootPath: "dotnet" which tells the LSP tool to run from the dotnet/ subdirectory. So the paths in the config are relative to that - GitHub.Copilot.SDK.sln is correct.

packageId: For local tool manifests (dotnet-tools.json), the tool name key (csharp-ls) serves as the package identifier. The packageId field is only required when using dotnet tool install directly. This is valid dotnet-tools.json format.

rollForward: Fixed - removed the explicit false to allow default patch roll-forward behavior.