Add onboarding MCP server for new contributors

.gitignore

@@ -21,6 +21,7 @@ test.txt
 *.log
 *.vsix
 **/.vscode/CMakeTools
+.vscode/mcp.json
 **/nls.*.json
 **/*.nls.json
 **/*.nls.*.json

CONTRIBUTING.md

@@ -2,6 +2,22 @@
 
 This article is for developers who want to contribute to the CMake Tools open source project.
 
+## New here? Try the onboarding assistant
+
+This repo includes an MCP server that gives GitHub Copilot structured knowledge about the codebase. It can walk you through setup, explain concepts like kits and presets, point you to the right source files, and help you find issues to work on.
+
+To set it up, build it once:
+
+```bash
+cd tools/onboarding-mcp
+yarn install
+yarn build
+```
+
+Then open **Copilot Chat** in VS Code (`Ctrl+Shift+I`), switch to **Agent mode**, and ask anything — for example *"How do I set up this repo?"* or *"What's a good first issue?"*
+
+See [`tools/onboarding-mcp/README.md`](tools/onboarding-mcp/README.md) for full details and example prompts.
+
 ## Build the CMake Tools extension
 
 As with most VS Code extensions, you'll need [Node.JS](https://nodejs.org/en/) installed. We use yarn to compile the code (run `npm install -g yarn` to install it).

tools/onboarding-mcp/.eslintignore

@@ -0,0 +1,2 @@
+dist/
+node_modules/

tools/onboarding-mcp/.eslintrc.cjs

@@ -0,0 +1,18 @@
+/** @type {import("eslint").Linter.Config} */
+module.exports = {
+    root: true,
+    parser: "@typescript-eslint/parser",
+    parserOptions: {
+        project: "./tsconfig.json",
+        sourceType: "module"
+    },
+    plugins: ["@typescript-eslint"],
+    extends: [
+        "eslint:recommended",
+        "plugin:@typescript-eslint/recommended"
+    ],
+    rules: {
+        // Keep it simple — this is a small standalone tool
+        "@typescript-eslint/no-unused-vars": ["warn", { argsIgnorePattern: "^_" }]
+    }
+};

tools/onboarding-mcp/README.md

@@ -0,0 +1,101 @@
+# CMake Tools Onboarding MCP Server
+
+A [Model Context Protocol](https://modelcontextprotocol.io/) (MCP) server that helps new contributors onboard to the [vscode-cmake-tools](https://github.com/microsoft/vscode-cmake-tools) extension. It provides Copilot agent mode with structured, repo-specific knowledge about setup, code structure, and PR requirements.
+
+## Install and build
+
+```bash
+cd tools/onboarding-mcp
+yarn install
+yarn build
+```
+
+## Wire it up in VS Code
+
+Create (or add to) **`.vscode/mcp.json`** at the workspace root:
+
+```json
+{
+    "servers": {
+        "cmake-tools-onboarding": {
+            "type": "stdio",
+            "command": "node",
+            "args": ["${workspaceFolder}/tools/onboarding-mcp/dist/index.js"],
+            "env": {
+                "GITHUB_TOKEN": "${env:GITHUB_TOKEN}"
+            }
+        }
+    }
+}
+```
+
+The `GITHUB_TOKEN` env var is **optional** but recommended. Without it, GitHub API calls are limited to 60 requests/hour. With a token, the limit is 5,000/hour. You can create a personal access token at https://github.com/settings/tokens — no scopes are needed for public repos.
+
+Once configured, the MCP server is available to Copilot agent mode (and any other MCP client) in VS Code.
+
+## Usage
+
+The MCP server works **inside GitHub Copilot Chat** in VS Code. After building and wiring it up (see [above](#wire-it-up-in-vs-code)), just open Copilot Chat and go:
+
+```bash
+cd tools/onboarding-mcp
+yarn install
+yarn build
+```
+
+Then open a **Copilot Chat** panel (press `Ctrl+Shift+I` or click the Copilot icon in the sidebar) and switch to **Agent mode** (the dropdown at the top of the chat panel). VS Code may show a notification asking you to start the MCP server — click **Start**.
+
+Once it's running, just ask questions in natural language. Copilot will automatically call the right tools. Here are some things you can try:
+
+### Getting started
+- *"How do I set up this repo for local development?"*
+- *"Walk me through building and running the extension."*
+
+### Understanding the codebase
+- *"What is a kit? How is it different from a preset?"*
+- *"Explain how the CMake driver works."*
+- *"Where is the code that handles CTest?"*
+- *"Which source file should I look at for build logic?"*
+
+### Finding documentation
+- *"Show me the docs page about CMake Presets."*
+- *"Where can I find troubleshooting info?"*
+
+### Exploring issues to work on
+- *"What are some good issues for a new contributor?"*
+- *"Show me recent open issues labeled 'enhancement'."*
+
+### Understanding recent activity
+- *"What areas of the codebase have changed recently?"*
+- *"Show me the last 5 commits to main."*
+
+### Preparing a PR
+- *"I changed the preset loading logic and added a new setting. Is my PR ready?"*
+- *"What do I need to check before submitting a PR?"*
+
+> **Tip:** You don't need to name the tools or remember their inputs. Just describe what you need and Copilot will figure out which tool to call.
+
+## Development
+
+```bash
+# Run the server in dev mode (uses tsx, no build step needed):
+yarn dev
+
+# Build for production:
+yarn build
+
+# Run the production build:
+yarn start
+```
+
+## Available tools
+
+| Tool | Input | Description |
+| --- | --- | --- |
+| **`get_setup_guide`** | _(none)_ | Returns an ordered list of setup steps for new contributors to build and run the extension locally. Each step includes a number, title, optional shell command, and optional notes. |
+| **`check_pr_readiness`** | `{ "changes": "..." }` | Given a free-text description of changes, returns a checklist of PR requirements from CONTRIBUTING.md. Each item includes the rule, a status (`"pass"`, `"warn"`, or `"manual_check_required"`), and a helpful hint. Items are flagged as `"warn"` when the description suggests a potential issue (e.g. mentioning `package.json` changes). |
+| **`explain_concept`** | `{ "concept": "..." }` | Explains a CMake Tools concept (e.g. `kit`, `preset`, `driver`, `ctest`, `build`, `configure`, `debug`, `settings`). Returns a summary, detailed explanation, related concepts, relevant source files, and a link to the docs page. If the concept is unknown, lists all known concepts. |
+| **`find_source_file`** | `{ "feature": "..." }` | Given a natural-language description (e.g. `"kit scanning"`, `"build logic"`, `"test runner"`), returns matching source files with GitHub links, descriptions, and relevance notes. Useful for quickly navigating to the right file. |
+| **`get_docs_page`** | `{ "topic": "..." }` | Given a topic (e.g. `presets`, `kits`, `debugging`, `troubleshooting`, `faq`), returns the matching documentation page with file path, GitHub URL, summary, and key section headings. |
+| **`get_contributor_issues`** | `{ "limit?": 20, "label?": "..." }` | Fetches recently updated open issues and enriches each with contributor-friendliness signals. Optionally filter by label (e.g. `"bug"`, `"enhancement"`, `"good first issue"`, `"help wanted"`). Requires a network connection; set `GITHUB_TOKEN` for higher rate limits (see [above](#wire-it-up-in-vs-code)). |
+| **`get_recent_changes`** | `{ "limit?": 10 }` | Fetches the most recent commits to main and annotates each with `affectedAreas` derived from the codebase source map. Includes a summary of the most active areas so new contributors can see what's currently in flux. |

tools/onboarding-mcp/package.json

@@ -0,0 +1,24 @@
+{
+    "name": "cmake-tools-onboarding-mcp",
+    "version": "1.0.0",
+    "private": true,
+    "description": "MCP server to help new contributors onboard to microsoft/vscode-cmake-tools",
+    "type": "module",
+    "engines": {
+        "node": ">=18"
+    },
+    "scripts": {
+        "build": "tsc",
+        "dev": "tsx src/index.ts",
+        "start": "node dist/index.js"
+    },
+    "dependencies": {
+        "@modelcontextprotocol/sdk": "^1.27.1",
+        "zod": "^3.25.0"
+    },
+    "devDependencies": {
+        "@types/node": "^22.0.0",
+        "tsx": "^4.19.0",
+        "typescript": "^5.7.0"
+    }
+}