first commit

README.md

@@ -0,0 +1,37 @@
+# YouTube MCP Server
+
+Uses `yt-dlp` to download YouTube content and connects it to LLMs via [Model Context Protocol](https://modelcontextprotocol.io/introduction). 
+
+## Features
+
+- Download YouTube subtitles (SRT format) for LLMs to read
+- Download YouTube videos to your Downloads folder
+- Integrates with Claude.ai and other MCP-compatible LLMs
+
+## Installation
+
+1. Install `yt-dlp` (Homebrew and WinGet both work great here)
+2. Install this via [dive](https://github.com/OpenAgentPlatform/Dive):
+   ```bash
+   mcp-installer install @kevinwatt/yt-dlp-mcp
+   ```
+
+## Usage Examples
+
+Ask your LLM to:
+- "Summarize the YouTube video <<URL>>"
+- "Download this YouTube video: <<URL>>"
+
+## Manual Start
+
+If needed, you can start the server manually:
+```bash
+yt-dlp-mcp
+```
+
+## Requirements
+
+- `yt-dlp` installed and in PATH
+- Node.js 20+
+- MCP-compatible LLM service
+

eslint.config.mjs

@@ -0,0 +1,88 @@
+import typescriptEslint from "@typescript-eslint/eslint-plugin";
+import prettier from "eslint-plugin-prettier";
+import tsParser from "@typescript-eslint/parser";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import js from "@eslint/js";
+import { FlatCompat } from "@eslint/eslintrc";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+  baseDirectory: __dirname,
+  recommendedConfig: js.configs.recommended,
+  allConfig: js.configs.all,
+});
+
+export default [
+  ...compat.extends(
+    "eslint:recommended",
+    "prettier",
+    "plugin:@typescript-eslint/eslint-recommended",
+    "plugin:@typescript-eslint/recommended",
+  ),
+  {
+    files: ["./src/*.{ts,tsx}", "./test/*.{ts,tsx}"],
+    plugins: {
+      "@typescript-eslint": typescriptEslint,
+      prettier,
+    },
+
+    languageOptions: {
+      globals: {},
+      parser: tsParser,
+      ecmaVersion: 5,
+      sourceType: "script",
+
+      parserOptions: {
+        project: "./tsconfig.json",
+      },
+    },
+
+    rules: {
+      "prettier/prettier": "warn",
+
+      "spaced-comment": [
+        "error",
+        "always",
+        {
+          markers: ["/"],
+        },
+      ],
+
+      "no-fallthrough": "error",
+      "@typescript-eslint/ban-ts-comment": "warn",
+
+      "@typescript-eslint/consistent-type-imports": [
+        "error",
+        {
+          prefer: "type-imports",
+        },
+      ],
+
+      "@typescript-eslint/no-inferrable-types": [
+        "error",
+        {
+          ignoreParameters: false,
+          ignoreProperties: false,
+        },
+      ],
+
+      "@typescript-eslint/no-non-null-assertion": "off",
+      "@typescript-eslint/no-floating-promises": "error",
+
+      "@typescript-eslint/no-unused-vars": [
+        "warn",
+        {
+          args: "after-used",
+          argsIgnorePattern: "^_",
+          varsIgnorePattern: "^_",
+          ignoreRestSiblings: true,
+        },
+      ],
+
+      "@typescript-eslint/no-empty-function": ["error"],
+      "@typescript-eslint/restrict-template-expressions": "off",
+    },
+  },
+];

package.json

@@ -0,0 +1,30 @@
+{
+  "name": "@kevinwatt/yt-dlp-mcp",
+  "version": "0.5.1",
+  "bin": {
+    "yt-dlp-mcp": "lib/index.mjs"
+  },
+  "description": "YouTube video download for MCP",
+  "main": "./lib/index.mjs",
+  "scripts": {
+    "prepare": "tsc && shx chmod +x ./lib/index.mjs"
+  },
+  "author": "Dewei Yen <k@funmula.com>",
+  "license": "MIT",
+  "type": "module",
+  "exports": {
+    ".": {
+      "import": "./lib/index.mjs"
+    }
+  },
+  "dependencies": {
+    "@modelcontextprotocol/sdk": "0.7.0",
+    "rimraf": "^6.0.1",
+    "spawn-rx": "^4.0.0"
+  },
+  "devDependencies": {
+    "shx": "^0.3.4",
+    "ts-node": "^10.9.2",
+    "typescript": "^5.6.3"
+  }
+}

src/index.mts

@@ -0,0 +1,190 @@
+#!/usr/bin/env node
+
+import { Server } from "@modelcontextprotocol/sdk/server/index.js";
+import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
+import {
+  CallToolRequestSchema,
+  ListToolsRequestSchema,
+} from "@modelcontextprotocol/sdk/types.js";
+import type { CallToolRequest } from "@modelcontextprotocol/sdk/types.js";
+
+import * as os from "os";
+import * as fs from "fs";
+import * as path from "path";
+import { spawnPromise } from "spawn-rx";
+import { rimraf } from "rimraf";
+
+const server = new Server(
+  {
+    name: "yt-dlp-mcp",
+    version: "0.5.1",
+  },
+  {
+    capabilities: {
+      tools: {},
+    },
+  }
+);
+
+/**
+ * Returns the list of available tools.
+ */
+server.setRequestHandler(ListToolsRequestSchema, async () => {
+  return {
+    tools: [
+      {
+        name: "download_youtube_srt",
+        description:
+          "Download YouTube subtitles in SRT format so that LLM can read them.",
+        inputSchema: {
+          type: "object",
+          properties: {
+            url: { type: "string", description: "URL of the YouTube video" },
+          },
+          required: ["url"],
+        },
+      },
+      {
+        name: "download_youtube_video",
+        description:
+          "Download YouTube video to the user's default Downloads folder (usually ~/Downloads).",
+        inputSchema: {
+          type: "object",
+          properties: {
+            url: { type: "string", description: "URL of the YouTube video" },
+          },
+          required: ["url"],
+        },
+      },
+    ],
+  };
+});
+
+/**
+ * Downloads YouTube subtitles (SRT format) and returns the concatenated content.
+ * @param url The URL of the YouTube video.
+ * @returns Concatenated subtitles text.
+ */
+async function downloadSubtitles(url: string): Promise<string> {
+  // Create a temporary directory for subtitle downloads
+  const tempDirectory = fs.mkdtempSync(path.join(os.tmpdir(), "youtube-"));
+
+  // Use yt-dlp to download subtitles without downloading the video
+  await spawnPromise(
+    "yt-dlp",
+    [
+      "--write-sub",
+      "--write-auto-sub",
+      "--sub-lang",
+      "en",
+      "--skip-download",
+      "--sub-format",
+      "srt",
+      url,
+    ],
+    { cwd: tempDirectory, detached: true }
+  );
+
+  let subtitlesContent = "";
+  try {
+    const files = fs.readdirSync(tempDirectory);
+    for (const file of files) {
+      const filePath = path.join(tempDirectory, file);
+      const fileData = fs.readFileSync(filePath, "utf8");
+      subtitlesContent += `${file}\n====================\n${fileData}\n\n`;
+    }
+  } finally {
+    // Clean up the temporary directory after processing
+    rimraf.sync(tempDirectory);
+  }
+  return subtitlesContent;
+}
+
+/**
+ * Downloads a YouTube video to the user's default Downloads folder.
+ * @param url The URL of the YouTube video.
+ * @returns A success message.
+ */
+async function downloadVideo(url: string): Promise<string> {
+  // Determine the user's Downloads directory (works for Windows, macOS, and Linux by default)
+  const userDownloadsDir = path.join(os.homedir(), "Downloads");
+
+  // Use yt-dlp to download the video into the Downloads folder using a default filename template
+  await spawnPromise("yt-dlp", [
+    url,
+    "-o",
+    path.join(userDownloadsDir, "%(title)s.%(ext)s"),
+  ]);
+
+  return `Video successfully downloaded to ${userDownloadsDir}`;
+}
+
+/**
+ * Handles tool execution requests.
+ */
+server.setRequestHandler(
+  CallToolRequestSchema,
+  async (request: CallToolRequest) => {
+    const toolName = request.params.name;
+    const args = request.params.arguments as { url: string };
+
+    if (toolName === "download_youtube_srt") {
+      try {
+        const subtitles = await downloadSubtitles(args.url);
+        return {
+          content: [
+            {
+              type: "text",
+              text: subtitles,
+            },
+          ],
+        };
+      } catch (error) {
+        return {
+          content: [
+            {
+              type: "text",
+              text: `Error downloading subtitles: ${error}`,
+            },
+          ],
+          isError: true,
+        };
+      }
+    } else if (toolName === "download_youtube_video") {
+      try {
+        const message = await downloadVideo(args.url);
+        return {
+          content: [
+            {
+              type: "text",
+              text: message,
+            },
+          ],
+        };
+      } catch (error) {
+        return {
+          content: [
+            {
+              type: "text",
+              text: `Error downloading video: ${error}`,
+            },
+          ],
+          isError: true,
+        };
+      }
+    } else {
+      throw new Error(`Unknown tool: ${toolName}`);
+    }
+  }
+);
+
+/**
+ * Starts the server using Stdio transport.
+ */
+async function startServer() {
+  const transport = new StdioServerTransport();
+  await server.connect(transport);
+}
+
+// Start the server and handle potential errors
+startServer().catch(console.error);

tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    "removeComments": false,
+    "preserveConstEnums": true,
+    "sourceMap": true,
+    "declaration": true,
+    "noImplicitAny": true,
+    "noImplicitReturns": true,
+    "strictNullChecks": true,
+    "noUnusedLocals": true,
+    "noImplicitThis": true,
+    "noUnusedParameters": true,
+    "module": "node16",
+    "moduleResolution": "node16",
+    "pretty": true,
+    "target": "es2015",
+    "outDir": "lib",
+    "lib": ["dom", "es2015"],
+    "esModuleInterop": true,
+    "allowJs": true
+  },
+  "formatCodeOptions": {
+    "indentSize": 2,
+    "tabSize": 2
+  },
+  "include": ["src/**/*.mts", "src/types/*.d.ts"],
+  "exclude": ["node_modules", "lib"]
+}