Gamma MCP Server

GAMMA_API_KEY="your_actual_gamma_api_key_here"

If theGAMMA_API_KEYis not found in the environment (e.g., if the.envfile is missing or the key isn't set), the server will log a fatal error and exit upon starting.

Understanding the Server Code (src/index.ts)

Let's break down the key parts of thesrc/index.tsfile:

import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js"; import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js"; import { z } from "zod"; import fetch from "node-fetch";

These lines import the necessary MCP server classes, Zod for schema definition and validation, andnode-fetchfor making HTTP requests.

const GAMMA_API_URL = "https://api.gamma.app/public-api/v0.1/generate"; const GAMMA_API_KEY = "YOUR_GAMMA_API_KEY_HERE"; // Replace or use env var

This sets up the base URL for the Gamma API and the API key.

const server = new McpServer({ name: "gamma-presentation", version: "1.0.0", capabilities: { resources: {}, tools: {}, }, });

This initializes a new MCP server with a name and version.

- inputText: The main topic or prompt.
- tone: Optional, e.g., 'humorous and sarcastic'.
- audience: Optional, e.g., 'students'.
- textAmount: Optional, 'short', 'medium', or 'long'.
- textMode: Optional, 'generate' or 'summarize'.
- numCards: Optional, number of slides (1-20).
- And others likeimageModel,imageStyle,editorMode,additionalInstructions.

Alternatively, you can add a script to yourpackage.json:

// package.json "scripts": { "start": "ts-node src/index.ts", // if you compile to JS first: // "build": "tsc", // "start:prod": "node dist/index.js" },

The server is now running and waiting for an MCP client to connect via stdio.

Testing Your Server with Claude for Desktop

To use this server with Claude for Desktop, you need to configure Claude for Desktop to know how to launch your server.
-

If the file or directories don't exist, create them.

- Fornpx: Runwhich npx(macOS/Linux) orwhere npx(Windows).
- Often,npxis used, which then findsts-nodein your project'snode_modules/.binor globally. If Claude has trouble withnpx, you might need to provide the direct path tots-node.
- A more robust way for thecommandmight be to use the absolute path to your Node.js executable, and then specifyts-nodeandsrc/index.tsas arguments, ensuring thecwd(Current Working Directory) is set correctly.

You will also need to ensure that theGAMMA_API_KEYenvironment variable is available to the process launched by Claude for Desktop. How to do this depends on your OS and how Claude for Desktop launches processes. Some common methods include:

- Setting the environment variable globally on your system.
- If Claude for Desktop is launched from a terminal whereGAMMA_API_KEYis already exported, it might inherit it.
- Modifying thecommandorargsinclaude_desktop_config.jsonto explicitly pass the environment variable if your shell/Node.js setup allows (e.g.,"command": "env", "args": ["GAMMA_API_KEY=your_key", "npx", "ts-node", ...]- this can be tricky and OS-dependent).
- Using a wrapper script as thecommandthat first sets the environment variable and then executesnpx ts-node src/index.ts.

A simple way for testing is often to ensureGAMMA_API_KEYis set in your user's global shell environment (e.g., in~/.bashrc,~/.zshrc, or system-wide environment variables on Windows) before launching Claude for Desktop.

{ "mcpServers": { "gamma-presentation-generator": { "command": "npx", // Or absolute path to npx, or node "args": [ "ts-node", // If command is 'npx' // If command is absolute path to node: // "/PATH/TO/gamma-mcp-server/node_modules/ts-node/dist/bin.js", "src/index.ts" ], "cwd": "/ABSOLUTE/PATH/TO/YOUR/gamma-mcp-server" // Current Working Directory for the server } } }

- "gamma-presentation-generator": This is the name you give to your server configuration within Claude. It can be anything descriptive.
- "command": The executable to run.npxis convenient as it resolvests-nodefrom your project. If this causes issues, use the absolute path to your Node.js executable.
- "args": Arguments passed to the command.

- Ifcommandisnpx, the first arg ists-node, followed by the path to your main server file (src/index.ts), relative to thecwd.
- Ifcommandis an absolute path tonode, args would be["/ABSOLUTE/PATH/TO/YOUR/gamma-mcp-server/node_modules/ts-node/dist/bin.js", "src/index.ts"]or similar, making surets-node's entry script is correctly referenced.

- Look for the tool icon (often a hammer знают) in the Claude for Desktop interface. Clicking it should show yourgenerate-presentationtool.
- Try prompting Claude:

- "Generate a presentation about the future of artificial intelligence."
- "Make a presentation on sustainable energy sources, targeting college students, make it medium length."
- "Use the gamma tool to create a short, humorous presentation for developers about the importance of documentation."

Claude should recognize the request, identify your tool, and (after your approval if configured) execute it. Your server (running in its own terminal or process) will then call the Gamma API, and the link to the presentation should appear in Claude's response.

When you ask a question in Claude for Desktop:
- The client (Claude for Desktop) sends your question to the Claude LLM.
- Claude analyzes the available tools (including yourgenerate-presentationtool) and decides if and how to use it.
- If Claude decides to use your tool, it sends a request to Claude for Desktop.
- Claude for Desktop executes the chosen tool by communicating with your MCP server (which it launched based onclaude_desktop_config.json) over stdio.
- Your server runs the tool logic (calls the Gamma API).
- The results (presentation URL or error) are sent back from your server to Claude for Desktop, then to the LLM.
- Claude formulates a natural language response incorporating the tool's output.
- The response is displayed to you!