Cal.com FastMCP Server

1# Cal.com FastMCP Server
2
3> ⚠️ **Disclaimer**: This project is not affiliated with or endorsed by Cal.com. I am an independent developer and have no association with Cal.com in any official capacity.
4
5This project provides a FastMCP server for interacting with the Cal.com API. It allows Language Learning Models (LLMs) to use tools to connect with important Cal.com functionalities like managing event types and bookings.
6
7## Prerequisites
8
9- Python 3.8+
10- A Cal.com account and API Key (v2)
11
12## Setup
13
141.  **Clone the repository (if applicable) or download the files.**
15    ```bash
16    git clone https://github.com/Danielpeter-99/calcom-mcp.git
17    cd calcom-mcp
18    ```
19    
202.  **Create a virtual environment (recommended):**
21    ```bash
22    python -m venv venv
23    source venv/bin/activate  # On Windows: venv\Scripts\activate
24    ```
25
263.  **Install dependencies:**
27    ```bash
28    pip install -r requirements.txt
29    ```
30
314.  **Set up the Cal.com API Key:**
32    You need to set the `CALCOM_API_KEY` environment variable. You can get your API key from your Cal.com settings page (usually under Developer or Security settings).
33
34    -   **Linux/macOS:**
35        ```bash
36        export CALCOM_API_KEY="your_actual_api_key_here"
37        ```
38        To make it permanent, add this line to your shell configuration file (e.g., `.bashrc`, `.zshrc`).
39
40    -   **Windows (PowerShell):**
41        ```powershell
42        $env:CALCOM_API_KEY="your_actual_api_key_here"
43        ```
44        To make it permanent, you can set it through the System Properties > Environment Variables.
45
46## Running the Server
47
48Once the setup is complete, you can run the FastMCP server:
49
50```bash
51fastmcp run app.py --transport sse --port 8010
52```
53
54The server will start at localhost:8010, and you should see output indicating it's running. If the `CALCOM_API_KEY` is not set, a warning will be displayed.
55
56## Available Tools
57
58The server currently provides the following tools for LLM interaction:
59
60-   `get_api_status()`: Check if the Cal.com API key is configured in the environment. Returns a string indicating the status.
61-   `list_event_types()`: Fetch a list of all event types from Cal.com for the authenticated account. Returns a dictionary with the list of event types or an error message.
62-   `get_bookings(...)`: Fetch a list of bookings from Cal.com, with optional filters (event_type_id, user_id, status, date_from, date_to, limit). Returns a dictionary with the list of bookings or an error message.
63-   `create_booking(...)`: Create a new booking in Cal.com for a specific event type and attendee. Requires parameters like start_time, attendee details, and event type identifiers. Returns a dictionary with booking details or an error message.
64-   `list_schedules(...)`: List all schedules available to the authenticated user or for a specific user/team. Optional filters: user_id, team_id, limit. Returns a dictionary with the list of schedules or an error message.
65-   `list_teams(...)`: List all teams available to the authenticated user. Optional filter: limit. Returns a dictionary with the list of teams or an error message.
66-   `list_users(...)`: List all users available to the authenticated account. Optional filter: limit. Returns a dictionary with the list of users or an error message.
67-   `list_webhooks(...)`: List all webhooks configured for the authenticated account. Optional filter: limit. Returns a dictionary with the list of webhooks or an error message.
68
69**Note:** All tools require the `CALCOM_API_KEY` environment variable to be set. If it is not set, tools will return a structured error message.
70
71## Tool Usage and Error Handling
72
73- All tools return either the API response (as a dictionary or string) or a structured error message with details about the failure.
74- Error messages include the type of error, HTTP status code (if applicable), and the response text from the Cal.com API.
75- For best results, always check for the presence of an `error` key in the response before using the returned data.
76- Tools are designed to be robust and provide informative feedback for both successful and failed API calls.
77
78## Development Notes
79
80-   The Cal.com API base URL is set to `https://api.cal.com/v2`.
81-   Authentication is primarily handled using a Bearer token with the `CALCOM_API_KEY`.
82-   The `create_booking` tool uses the `cal-api-version: 2024-08-13` header as specified in the Cal.com API v2 documentation for that endpoint.
83-   Error handling is included in the API calls to provide informative responses.
84
85## 🚀 Built With
86
87[![Python](https://img.shields.io/badge/Python-3.8+-blue?logo=python&logoColor=white)](https://www.python.org/)  
88[![FastMCP](https://img.shields.io/badge/FastMCP-Framework-8A2BE2?logo=fastapi&logoColor=white)](https://github.com/jlowin/fastmcp)  
89[![Cal.com API](https://img.shields.io/badge/Cal.com%20API-v2-00B8A9?logo=google-calendar&logoColor=white)](https://cal.com/docs/api-reference/v2/introduction)  
90
91
92## Important Security Note
93
94**Never hardcode your `CALCOM_API_KEY` directly into the source code.** Always use environment variables as described in the setup instructions to keep your API key secure.
95