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---
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title: "Quickstart"
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description: "Get started with building your first MCP server and connecting it to a host"
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---
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In this tutorial, we'll build a simple MCP weather server and connect it to a host, Claude for Desktop. We'll start with a basic setup, and then progress to more complex use cases.
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### What we'll be building
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Many LLMs (including Claude) do not currently have the ability to fetch the forecast and severe weather alerts. Let's use MCP to solve that!
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We'll build a server that exposes two tools: `get-alerts` and `get-forecast`. Then we'll connect the server to an MCP host (in this case, Claude for Desktop):
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<Frame>
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<img src="/images/weather-alerts.png" />
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</Frame>
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<Frame>
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<img src="/images/current-weather.png" />
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</Frame>
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<Note>
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Servers can connect to any client. We've chosen Claude desktop here for simplicity, but we also have guides on [building your own client](/tutorials/building-a-client).
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</Note>
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<Accordion title="Why Claude for Desktop and not Claude.ai?">
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Because servers are locally run, MCP currently only supports desktop hosts. Remote hosts are in active development.
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</Accordion>
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### Core MCP Concepts
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MCP servers can provide three main types of capabilities:
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1. **Resources**: File-like data that can be read by clients (like API responses or file contents)
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2. **Tools**: Functions that can be called by the LLM (with user approval)
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3. **Prompts**: Pre-written templates that help users accomplish specific tasks
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This tutorial focuses on tools, but we have intermediate tutorials if you'd like to learn more about Resources and Prompts.
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<Tabs>
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<Tab title='Python'>
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### Prerequisite knowledge
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This quickstart assumes you have familiarity with:
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- Python
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- LLMs like Claude
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### System requirements
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For Python, make sure you have Python 3.9 or higher installed.
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### Set up your environment
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First, let's install `uv` and set up our Python project and environment:
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<CodeGroup>
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```bash MacOS/Linux
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curl -LsSf https://astral.sh/uv/install.sh | sh
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```
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```powershell Windows
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powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"
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```
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</CodeGroup>
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Make sure to restart your terminal afterwards to ensure that the `uv` command gets picked up.
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Now, let's create and set up our project:
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<CodeGroup>
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```bash MacOS/Linux
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# Create a new directory for our project
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uv init weather
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cd weather
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# Create virtual environment and activate it
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uv venv
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source .venv/bin/activate
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# Install dependencies
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uv add mcp httpx
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# Remove template file
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rm hello.py
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# Create our files
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mkdir -p src/weather
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touch src/weather/__init__.py
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touch src/weather/server.py
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```
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```powershell Windows
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# Create a new directory for our project
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uv init weather
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cd weather
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# Create virtual environment and activate it
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uv venv
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.venv\Scripts\activate
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# Install dependencies
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uv add mcp httpx
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# Clean up boilerplate code
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rm hello.py
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# Create our files
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md src
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md src\weather
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new-item src\weather\__init__.py
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new-item src\weather\server.py
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```
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</CodeGroup>
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Add this code to `pyproject.toml`:
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```toml
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...rest of config
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[build-system]
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requires = [ "hatchling",]
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build-backend = "hatchling.build"
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[project.scripts]
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weather = "weather:main"
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```
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Add this code to `__init__.py`:
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```python src/weather/__init__.py
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from . import server
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import asyncio
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def main():
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"""Main entry point for the package."""
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asyncio.run(server.main())
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# Optionally expose other important items at package level
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__all__ = ['main', 'server']
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```
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Now let's dive into building your server.
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## Building your server
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### Importing packages
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Add these to the top of your `server.py`:
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```python
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from typing import Any
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import asyncio
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import httpx
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from mcp.server.models import InitializationOptions
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import mcp.types as types
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from mcp.server import NotificationOptions, Server
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import mcp.server.stdio
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```
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### Setting up the instance
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Then initialize the server instance and the base URL for the NWS API:
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```python
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NWS_API_BASE = "https://api.weather.gov"
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USER_AGENT = "weather-app/1.0"
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server = Server("weather")
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```
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### Implementing tool listing
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We need to tell clients what tools are available. The `list_tools()` decorator registers this handler:
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```python
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@server.list_tools()
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async def handle_list_tools() -> list[types.Tool]:
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"""
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List available tools.
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Each tool specifies its arguments using JSON Schema validation.
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"""
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return [
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types.Tool(
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name="get-alerts",
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description="Get weather alerts for a state",
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inputSchema={
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"type": "object",
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"properties": {
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"state": {
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"type": "string",
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"description": "Two-letter state code (e.g. CA, NY)",
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},
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},
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"required": ["state"],
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},
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),
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types.Tool(
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name="get-forecast",
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description="Get weather forecast for a location",
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inputSchema={
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"type": "object",
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"properties": {
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"latitude": {
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"type": "number",
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"description": "Latitude of the location",
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},
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"longitude": {
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"type": "number",
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"description": "Longitude of the location",
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},
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},
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"required": ["latitude", "longitude"],
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},
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),
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]
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```
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This defines our two tools: `get-alerts` and `get-forecast`.
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### Helper functions
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Next, let's add our helper functions for querying and formatting the data from the National Weather Service API:
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```python
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async def make_nws_request(client: httpx.AsyncClient, url: str) -> dict[str, Any] | None:
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"""Make a request to the NWS API with proper error handling."""
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headers = {
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"User-Agent": USER_AGENT,
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"Accept": "application/geo+json"
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}
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try:
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response = await client.get(url, headers=headers, timeout=30.0)
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response.raise_for_status()
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return response.json()
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except Exception:
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return None
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def format_alert(feature: dict) -> str:
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"""Format an alert feature into a concise string."""
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props = feature["properties"]
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return (
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f"Event: {props.get('event', 'Unknown')}\n"
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f"Area: {props.get('areaDesc', 'Unknown')}\n"
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f"Severity: {props.get('severity', 'Unknown')}\n"
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f"Status: {props.get('status', 'Unknown')}\n"
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f"Headline: {props.get('headline', 'No headline')}\n"
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"---"
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)
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```
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### Implementing tool execution
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The tool execution handler is responsible for actually executing the logic of each tool. Let's add it:
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```python
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@server.call_tool()
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async def handle_call_tool(
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name: str, arguments: dict | None
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) -> list[types.TextContent | types.ImageContent | types.EmbeddedResource]:
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"""
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Handle tool execution requests.
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Tools can fetch weather data and notify clients of changes.
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"""
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if not arguments:
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raise ValueError("Missing arguments")
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if name == "get-alerts":
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state = arguments.get("state")
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if not state:
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raise ValueError("Missing state parameter")
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# Convert state to uppercase to ensure consistent format
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state = state.upper()
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if len(state) != 2:
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raise ValueError("State must be a two-letter code (e.g. CA, NY)")
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async with httpx.AsyncClient() as client:
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alerts_url = f"{NWS_API_BASE}/alerts?area={state}"
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alerts_data = await make_nws_request(client, alerts_url)
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if not alerts_data:
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return [types.TextContent(type="text", text="Failed to retrieve alerts data")]
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features = alerts_data.get("features", [])
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if not features:
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return [types.TextContent(type="text", text=f"No active alerts for {state}")]
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# Format each alert into a concise string
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formatted_alerts = [format_alert(feature) for feature in features[:20]] # only take the first 20 alerts
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alerts_text = f"Active alerts for {state}:\n\n" + "\n".join(formatted_alerts)
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return [
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types.TextContent(
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type="text",
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text=alerts_text
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)
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]
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elif name == "get-forecast":
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try:
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latitude = float(arguments.get("latitude"))
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longitude = float(arguments.get("longitude"))
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except (TypeError, ValueError):
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return [types.TextContent(
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type="text",
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text="Invalid coordinates. Please provide valid numbers for latitude and longitude."
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)]
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# Basic coordinate validation
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if not (-90 <= latitude <= 90) or not (-180 <= longitude <= 180):
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return [types.TextContent(
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type="text",
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text="Invalid coordinates. Latitude must be between -90 and 90, longitude between -180 and 180."
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)]
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async with httpx.AsyncClient() as client:
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# First get the grid point
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lat_str = f"{latitude}"
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lon_str = f"{longitude}"
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points_url = f"{NWS_API_BASE}/points/{lat_str},{lon_str}"
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points_data = await make_nws_request(client, points_url)
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if not points_data:
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return [types.TextContent(type="text", text=f"Failed to retrieve grid point data for coordinates: {latitude}, {longitude}. This location may not be supported by the NWS API (only US locations are supported).")]
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# Extract forecast URL from the response
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properties = points_data.get("properties", {})
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forecast_url = properties.get("forecast")
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if not forecast_url:
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return [types.TextContent(type="text", text="Failed to get forecast URL from grid point data")]
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# Get the forecast
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forecast_data = await make_nws_request(client, forecast_url)
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if not forecast_data:
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return [types.TextContent(type="text", text="Failed to retrieve forecast data")]
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# Format the forecast periods
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periods = forecast_data.get("properties", {}).get("periods", [])
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if not periods:
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return [types.TextContent(type="text", text="No forecast periods available")]
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# Format each period into a concise string
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formatted_forecast = []
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for period in periods:
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forecast_text = (
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f"{period.get('name', 'Unknown')}:\n"
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f"Temperature: {period.get('temperature', 'Unknown')}°{period.get('temperatureUnit', 'F')}\n"
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f"Wind: {period.get('windSpeed', 'Unknown')} {period.get('windDirection', '')}\n"
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f"{period.get('shortForecast', 'No forecast available')}\n"
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"---"
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)
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formatted_forecast.append(forecast_text)
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forecast_text = f"Forecast for {latitude}, {longitude}:\n\n" + "\n".join(formatted_forecast)
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return [types.TextContent(
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type="text",
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text=forecast_text
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)]
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else:
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raise ValueError(f"Unknown tool: {name}")
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```
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### Running the server
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Finally, implement the main function to run the server:
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```python
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async def main():
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# Run the server using stdin/stdout streams
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async with mcp.server.stdio.stdio_server() as (read_stream, write_stream):
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await server.run(
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read_stream,
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write_stream,
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InitializationOptions(
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server_name="weather",
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server_version="0.1.0",
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capabilities=server.get_capabilities(
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notification_options=NotificationOptions(),
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experimental_capabilities={},
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),
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),
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)
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# This is needed if you'd like to connect to a custom client
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if __name__ == "__main__":
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asyncio.run(main())
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```
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Your server is complete! Run `uv run src/weather/server.py` to confirm that everything's working.
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Let's now test your server from an existing MCP host, Claude for Desktop.
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## Testing your server with Claude for Desktop
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<Note>
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Claude for Desktop is not yet available on Linux. Linux users can proceed to the [Building a client](/tutorials/building-a-client) tutorial to build an MCP client that connects to the server we just built.
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</Note>
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First, make sure you have Claude for Desktop installed. [You can install the latest version here.](https://claude.ai/download)
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Next, open your Claude for Desktop App configuration at `~/Library/Application Support/Claude/claude_desktop_config.json` in a text editor.
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For example, if you have [VS Code](https://code.visualstudio.com/) installed:
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<Tabs>
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<Tab title="MacOS/Linux">
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```bash
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code ~/Library/Application\ Support/Claude/claude_desktop_config.json
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```
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</Tab>
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<Tab title="Windows">
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```powershell
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code $env:AppData\Claude\claude_desktop_config.json
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```
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</Tab>
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</Tabs>
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Add this configuration (replace the parent folder path):
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<Tabs>
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<Tab title="MacOS/Linux">
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```json Python
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{
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"mcpServers": {
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"weather": {
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"command": "uv",
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"args": [
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"--directory",
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"/ABSOLUTE/PATH/TO/PARENT/FOLDER/weather",
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"run",
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"weather"
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]
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}
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}
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}
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```
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</Tab>
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<Tab title="Windows">
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```json Python
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{
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"mcpServers": {
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"weather": {
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"command": "uv",
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"args": [
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"--directory",
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"C:\\ABSOLUTE\PATH\TO\PARENT\FOLDER\weather",
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"run",
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"weather"
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]
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}
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}
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}
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```
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</Tab>
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</Tabs>
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This tells Claude for Desktop:
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1. There's an MCP server named "weather"
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2. Launch it by running `uv --directory /ABSOLUTE/PATH/TO/PARENT/FOLDER/weather run weather`
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Save the file, and restart **Claude for Desktop**.
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</Tab>
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<Tab title="Node">
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### Prerequisite knowledge
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This quickstart assumes you have familiarity with:
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- TypeScript
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- LLMs like Claude
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|
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### System requirements
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For TypeScript, make sure you have the latest version of Node installed.
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### Set up your environment
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First, let's install Node.js and npm if you haven't already. You can download them from [nodejs.org](https://nodejs.org/).
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Verify your Node.js installation:
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```bash
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node --version
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npm --version
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```
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For this tutorial, you'll need Node.js version 16 or higher.
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|
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Now, let's create and set up our project:
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<CodeGroup>
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```bash MacOS/Linux
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# Create a new directory for our project
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mkdir weather
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cd weather
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# Initialize a new npm project
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npm init -y
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# Install dependencies
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npm install @modelcontextprotocol/sdk zod
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npm install -D @types/node typescript
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# Create our files
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mkdir src
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touch src/index.ts
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```
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|
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```powershell Windows
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# Create a new directory for our project
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md weather
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cd weather
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# Initialize a new npm project
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npm init -y
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# Install dependencies
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npm install @modelcontextprotocol/sdk zod
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npm install -D @types/node typescript
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# Create our files
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md src
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new-item src\index.ts
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```
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</CodeGroup>
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|
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Update your package.json to add type: "module" and a build script:
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|
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```json package.json
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{
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"type": "module",
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"bin": {
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"weather": "./build/index.js"
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},
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"scripts": {
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"build": "tsc && node -e \"require('fs').chmodSync('build/index.js', '755')\"",
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},
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"files": [
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"build"
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],
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}
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```
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|
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Create a `tsconfig.json` in the root of your project:
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|
|
```json tsconfig.json
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{
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"compilerOptions": {
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"target": "ES2022",
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"module": "Node16",
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"moduleResolution": "Node16",
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"outDir": "./build",
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"rootDir": "./src",
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"strict": true,
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"esModuleInterop": true,
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"skipLibCheck": true,
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"forceConsistentCasingInFileNames": true
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},
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"include": ["src/**/*"],
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"exclude": ["node_modules"]
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}
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|
```
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|
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Now let's dive into building your server.
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|
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## Building your server
|
|
|
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### Importing packages
|
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|
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Add these to the top of your `src/index.ts`:
|
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|
|
```typescript
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import { Server } from "@modelcontextprotocol/sdk/server/index.js";
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import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
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import {
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CallToolRequestSchema,
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ListToolsRequestSchema,
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|
} from "@modelcontextprotocol/sdk/types.js";
|
|
import { z } from "zod";
|
|
```
|
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|
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### Setting up the instance
|
|
|
|
Then initialize the NWS API base URL, validation schemas, and server instance:
|
|
|
|
```typescript
|
|
const NWS_API_BASE = "https://api.weather.gov";
|
|
const USER_AGENT = "weather-app/1.0";
|
|
|
|
// Define Zod schemas for validation
|
|
const AlertsArgumentsSchema = z.object({
|
|
state: z.string().length(2),
|
|
});
|
|
|
|
const ForecastArgumentsSchema = z.object({
|
|
latitude: z.number().min(-90).max(90),
|
|
longitude: z.number().min(-180).max(180),
|
|
});
|
|
|
|
// Create server instance
|
|
const server = new Server(
|
|
{
|
|
name: "weather",
|
|
version: "1.0.0",
|
|
},
|
|
{
|
|
capabilities: {
|
|
tools: {},
|
|
},
|
|
}
|
|
);
|
|
```
|
|
|
|
### Implementing tool listing
|
|
|
|
We need to tell clients what tools are available. This `server.setRequestHandler` call will register this list for us:
|
|
|
|
```typescript
|
|
// List available tools
|
|
server.setRequestHandler(ListToolsRequestSchema, async () => {
|
|
return {
|
|
tools: [
|
|
{
|
|
name: "get-alerts",
|
|
description: "Get weather alerts for a state",
|
|
inputSchema: {
|
|
type: "object",
|
|
properties: {
|
|
state: {
|
|
type: "string",
|
|
description: "Two-letter state code (e.g. CA, NY)",
|
|
},
|
|
},
|
|
required: ["state"],
|
|
},
|
|
},
|
|
{
|
|
name: "get-forecast",
|
|
description: "Get weather forecast for a location",
|
|
inputSchema: {
|
|
type: "object",
|
|
properties: {
|
|
latitude: {
|
|
type: "number",
|
|
description: "Latitude of the location",
|
|
},
|
|
longitude: {
|
|
type: "number",
|
|
description: "Longitude of the location",
|
|
},
|
|
},
|
|
required: ["latitude", "longitude"],
|
|
},
|
|
},
|
|
],
|
|
};
|
|
});
|
|
```
|
|
|
|
This defines our two tools: `get-alerts` and `get-forecast`.
|
|
|
|
### Helper functions
|
|
|
|
Next, let's add our helper functions for querying and formatting the data from the National Weather Service API:
|
|
|
|
```typescript
|
|
// Helper function for making NWS API requests
|
|
async function makeNWSRequest<T>(url: string): Promise<T | null> {
|
|
const headers = {
|
|
"User-Agent": USER_AGENT,
|
|
Accept: "application/geo+json",
|
|
};
|
|
|
|
try {
|
|
const response = await fetch(url, { headers });
|
|
if (!response.ok) {
|
|
throw new Error(`HTTP error! status: ${response.status}`);
|
|
}
|
|
return (await response.json()) as T;
|
|
} catch (error) {
|
|
console.error("Error making NWS request:", error);
|
|
return null;
|
|
}
|
|
}
|
|
|
|
interface AlertFeature {
|
|
properties: {
|
|
event?: string;
|
|
areaDesc?: string;
|
|
severity?: string;
|
|
status?: string;
|
|
headline?: string;
|
|
};
|
|
}
|
|
|
|
// Format alert data
|
|
function formatAlert(feature: AlertFeature): string {
|
|
const props = feature.properties;
|
|
return [
|
|
`Event: ${props.event || "Unknown"}`,
|
|
`Area: ${props.areaDesc || "Unknown"}`,
|
|
`Severity: ${props.severity || "Unknown"}`,
|
|
`Status: ${props.status || "Unknown"}`,
|
|
`Headline: ${props.headline || "No headline"}`,
|
|
"---",
|
|
].join("\n");
|
|
}
|
|
|
|
interface ForecastPeriod {
|
|
name?: string;
|
|
temperature?: number;
|
|
temperatureUnit?: string;
|
|
windSpeed?: string;
|
|
windDirection?: string;
|
|
shortForecast?: string;
|
|
}
|
|
|
|
interface AlertsResponse {
|
|
features: AlertFeature[];
|
|
}
|
|
|
|
interface PointsResponse {
|
|
properties: {
|
|
forecast?: string;
|
|
};
|
|
}
|
|
|
|
interface ForecastResponse {
|
|
properties: {
|
|
periods: ForecastPeriod[];
|
|
};
|
|
}
|
|
```
|
|
|
|
### Implementing tool execution
|
|
|
|
The tool execution handler is responsible for actually executing the logic of each tool. Let's add it:
|
|
|
|
```typescript
|
|
// Handle tool execution
|
|
server.setRequestHandler(CallToolRequestSchema, async (request) => {
|
|
const { name, arguments: args } = request.params;
|
|
|
|
try {
|
|
if (name === "get-alerts") {
|
|
const { state } = AlertsArgumentsSchema.parse(args);
|
|
const stateCode = state.toUpperCase();
|
|
|
|
const alertsUrl = `${NWS_API_BASE}/alerts?area=${stateCode}`;
|
|
const alertsData = await makeNWSRequest<AlertsResponse>(alertsUrl);
|
|
|
|
if (!alertsData) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: "Failed to retrieve alerts data",
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
const features = alertsData.features || [];
|
|
if (features.length === 0) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: `No active alerts for ${stateCode}`,
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
const formattedAlerts = features.map(formatAlert).slice(0, 20) // only take the first 20 alerts;
|
|
const alertsText = `Active alerts for ${stateCode}:\n\n${formattedAlerts.join(
|
|
"\n"
|
|
)}`;
|
|
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: alertsText,
|
|
},
|
|
],
|
|
};
|
|
} else if (name === "get-forecast") {
|
|
const { latitude, longitude } = ForecastArgumentsSchema.parse(args);
|
|
|
|
// Get grid point data
|
|
const pointsUrl = `${NWS_API_BASE}/points/${latitude.toFixed(
|
|
4
|
|
)},${longitude.toFixed(4)}`;
|
|
const pointsData = await makeNWSRequest<PointsResponse>(pointsUrl);
|
|
|
|
if (!pointsData) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: `Failed to retrieve grid point data for coordinates: ${latitude}, ${longitude}. This location may not be supported by the NWS API (only US locations are supported).`,
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
const forecastUrl = pointsData.properties?.forecast;
|
|
if (!forecastUrl) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: "Failed to get forecast URL from grid point data",
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
// Get forecast data
|
|
const forecastData = await makeNWSRequest<ForecastResponse>(forecastUrl);
|
|
if (!forecastData) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: "Failed to retrieve forecast data",
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
const periods = forecastData.properties?.periods || [];
|
|
if (periods.length === 0) {
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: "No forecast periods available",
|
|
},
|
|
],
|
|
};
|
|
}
|
|
|
|
// Format forecast periods
|
|
const formattedForecast = periods.map((period: ForecastPeriod) =>
|
|
[
|
|
`${period.name || "Unknown"}:`,
|
|
`Temperature: ${period.temperature || "Unknown"}°${
|
|
period.temperatureUnit || "F"
|
|
}`,
|
|
`Wind: ${period.windSpeed || "Unknown"} ${
|
|
period.windDirection || ""
|
|
}`,
|
|
`${period.shortForecast || "No forecast available"}`,
|
|
"---",
|
|
].join("\n")
|
|
);
|
|
|
|
const forecastText = `Forecast for ${latitude}, ${longitude}:\n\n${formattedForecast.join(
|
|
"\n"
|
|
)}`;
|
|
|
|
return {
|
|
content: [
|
|
{
|
|
type: "text",
|
|
text: forecastText,
|
|
},
|
|
],
|
|
};
|
|
} else {
|
|
throw new Error(`Unknown tool: ${name}`);
|
|
}
|
|
} catch (error) {
|
|
if (error instanceof z.ZodError) {
|
|
throw new Error(
|
|
`Invalid arguments: ${error.errors
|
|
.map((e) => `${e.path.join(".")}: ${e.message}`)
|
|
.join(", ")}`
|
|
);
|
|
}
|
|
throw error;
|
|
}
|
|
});
|
|
```
|
|
|
|
### Running the server
|
|
|
|
Finally, implement the main function to run the server:
|
|
|
|
```typescript
|
|
// Start the server
|
|
async function main() {
|
|
const transport = new StdioServerTransport();
|
|
await server.connect(transport);
|
|
console.error("Weather MCP Server running on stdio");
|
|
}
|
|
|
|
main().catch((error) => {
|
|
console.error("Fatal error in main():", error);
|
|
process.exit(1);
|
|
});
|
|
```
|
|
|
|
Make sure to run `npm run build` to build your server! This is a very important step in getting your server to connect.
|
|
|
|
Let's now test your server from an existing MCP host, Claude for Desktop.
|
|
|
|
## Testing your server with Claude for Desktop
|
|
|
|
<Note>
|
|
Unfortunately, Claude for Desktop is not yet available on Linux. Linux users can proceed to the [Building a client](/tutorials/building-a-client) tutorial for a workaround.
|
|
</Note>
|
|
|
|
First, make sure you have Claude for Desktop installed. [You can install the latest version here.](https://claude.ai/download)
|
|
|
|
Next, open your Claude for Desktop App configuration at `~/Library/Application Support/Claude/claude_desktop_config.json` in a text editor.
|
|
|
|
For example, if you have [VS Code](https://code.visualstudio.com/) installed:
|
|
|
|
<Tabs>
|
|
<Tab title="MacOS/Linux">
|
|
```bash
|
|
code ~/Library/Application\ Support/Claude/claude_desktop_config.json
|
|
```
|
|
</Tab>
|
|
<Tab title="Windows">
|
|
```powershell
|
|
code $env:AppData\Claude\claude_desktop_config.json
|
|
```
|
|
</Tab>
|
|
</Tabs>
|
|
|
|
|
|
Add this configuration (replace the parent folder path):
|
|
|
|
<Tabs>
|
|
<Tab title="MacOS/Linux">
|
|
<CodeGroup>
|
|
```json Node
|
|
{
|
|
"mcpServers": {
|
|
"weather": {
|
|
"command": "node",
|
|
"args": [
|
|
"/ABSOLUTE/PATH/TO/PARENT/FOLDER/weather/build/index.js"
|
|
]
|
|
}
|
|
}
|
|
}
|
|
```
|
|
</CodeGroup>
|
|
</Tab>
|
|
<Tab title="Windows">
|
|
<CodeGroup>
|
|
```json Node
|
|
{
|
|
"mcpServers": {
|
|
"weather": {
|
|
"command": "node",
|
|
"args": [
|
|
"C:\\PATH\TO\PARENT\FOLDER\weather\build\index.js"
|
|
]
|
|
}
|
|
}
|
|
}
|
|
```
|
|
</CodeGroup>
|
|
</Tab>
|
|
</Tabs>
|
|
|
|
This tells Claude for Desktop:
|
|
1. There's an MCP server named "weather"
|
|
2. Launch it by running `node /ABSOLUTE/PATH/TO/PARENT/FOLDER/weather/build/index.js`
|
|
|
|
Save the file, and restart **Claude for Desktop**.
|
|
</Tab>
|
|
</Tabs>
|
|
|
|
### Test with commands
|
|
|
|
First, make sure Claude for Desktop is picking up the two tools we've exposed in our `weather` server. You can do this by looking for the hammer <img src="/images/claude-desktop-mcp-hammer-icon.svg" style={{display: 'inline', margin: 0, height: '1.3em'}} /> icon:
|
|
|
|
<Frame>
|
|
<img src="/images/visual-indicator-mcp-tools.png" />
|
|
</Frame>
|
|
|
|
After clicking on the hammer icon, you should see two tools listed:
|
|
|
|
<Frame>
|
|
<img src="/images/available-mcp-tools.png" />
|
|
</Frame>
|
|
|
|
If your server isn't being picked up by Claude for Desktop, proceed to the [Troubleshooting](#troubleshooting) section for debugging advice.
|
|
|
|
You can now test your server by running the following commands in Claude for Desktop:
|
|
|
|
- What's the weather in Sacramento?
|
|
- What are the active weather alerts in Texas?
|
|
|
|
<Frame>
|
|
<img src="/images/current-weather.png" />
|
|
</Frame>
|
|
<Frame>
|
|
<img src="/images/weather-alerts.png" />
|
|
</Frame>
|
|
|
|
<Note>
|
|
Since this is the US National Weather service, the queries will only work for US locations.
|
|
</Note>
|
|
|
|
## What's happening under the hood
|
|
|
|
When you ask a question:
|
|
|
|
1. The client sends your question to Claude
|
|
2. Claude analyzes the available tools and decides which one(s) to use
|
|
3. The client executes the chosen tool(s) through the MCP server
|
|
4. The results are sent back to Claude
|
|
5. Claude formulates a natural language response
|
|
6. The response is displayed to you!
|
|
|
|
## Troubleshooting
|
|
|
|
<AccordionGroup>
|
|
<Accordion title="Weather API Issues">
|
|
**Error: Failed to retrieve grid point data**
|
|
|
|
This usually means either:
|
|
1. The coordinates are outside the US
|
|
2. The NWS API is having issues
|
|
3. You're being rate limited
|
|
|
|
Fix:
|
|
|
|
- Verify you're using US coordinates
|
|
- Add a small delay between requests
|
|
- Check the NWS API status page
|
|
|
|
**Error: No active alerts for [STATE]**
|
|
|
|
This isn't an error - it just means there are no current weather alerts for that state. Try a different state or check during severe weather.
|
|
</Accordion>
|
|
<Accordion title="Claude for Desktop Integration Issues">
|
|
**Server not showing up in Claude**
|
|
1. Check your configuration file syntax
|
|
2. Make sure the path to your project is correct
|
|
3. Restart Claude for Desktop completely
|
|
|
|
You can also check Claude's logs for errors like so:
|
|
```bash
|
|
# Check Claude's logs for errors
|
|
tail -n 20 -f ~/Library/Logs/Claude/mcp*.log
|
|
```
|
|
|
|
**Tool calls failing silently**
|
|
|
|
If Claude attempts to use the tools but they fail:
|
|
|
|
1. Check Claude's logs for errors
|
|
2. Verify your server runs without errors
|
|
3. Try restarting Claude for Desktop
|
|
</Accordion>
|
|
</AccordionGroup>
|
|
|
|
## Next steps
|
|
|
|
<CardGroup cols={2}>
|
|
<Card
|
|
title="Building a client"
|
|
icon="outlet"
|
|
href="/tutorials/building-a-client"
|
|
>
|
|
Learn how to build your an MCP client that can connect to your server
|
|
</Card>
|
|
<Card
|
|
title="Example servers"
|
|
icon="grid"
|
|
href="/examples"
|
|
>
|
|
Check out our gallery of official MCP servers and implementations
|
|
</Card>
|
|
<Card
|
|
title="Clients"
|
|
icon="cubes"
|
|
href="/clients"
|
|
>
|
|
Learn about other MCP clients such as Zed and Sourcegraph
|
|
</Card>
|
|
<Card
|
|
title="Building MCP with LLMs"
|
|
icon="comments"
|
|
href="/building-mcp-with-llms"
|
|
>
|
|
Learn how to use LLMs like Claude to speed up your MCP development
|
|
</Card>
|
|
</CardGroup> |