mcpapp1 — Weather MCP Server

A small Model Context Protocol server that exposes live US weather alerts to MCP clients such as Claude Desktop, Claude Code, and Cursor.

Data comes from the National Weather Service API, which is free and requires no API key.

What it exposes

Related MCP server: Weather Alert & Forecast MCP Tool

Requirements

• Python 3.13+

• uv

Setup

git clone https://github.com/eyosiasbisrat/mcpapp1.git
cd mcpapp1
uv sync

Running

Run the server directly over stdio:

uv run server/weather.py

Or via the MCP CLI:

uv run mcp run server/weather.py

Inspect it interactively in the MCP Inspector:

uv run mcp dev server/weather.py

An MCP server speaks JSON-RPC over stdin/stdout, so running it by hand just waits silently for input. That is expected — normally a client launches it for you.

Connecting a client

Claude Code / Cursor

Both configs are already checked in and use relative paths, so they work after uv sync with no edits:

• .mcp.json — Claude Code

• .cursor/mcp.json — Cursor

Reload the editor window and approve the server when prompted.

Claude Desktop

uv run mcp install server/weather.py

Then quit Claude Desktop completely — including the tray icon, since closing the window leaves it running — and reopen it.

If this prints Claude app not found while Claude Desktop is definitely installed, see below.

Troubleshooting

Claude app not found on Windows

mcp install looks for Claude Desktop's config in a fixed location:

%APPDATA%\Claude

If Claude Desktop was installed as an MSIX / Microsoft Store package, its data is redirected into the package container and that directory never exists:

%LOCALAPPDATA%\Packages\Claude_<id>\LocalCache\Roaming\Claude\claude_desktop_config.json

Two ways to resolve it.

Edit the real config directly — add an mcpServers entry to the claude_desktop_config.json at the packaged path above, keeping any existing keys intact.

Or bridge the paths once with a directory junction, after which mcp install works normally for every server:

cmd /c mklink /J "%APPDATA%\Claude" "%LOCALAPPDATA%\Packages\Claude_<id>\LocalCache\Roaming\Claude"

Substitute your actual package folder name for Claude_<id>. To undo it, cmd /c rmdir "%APPDATA%\Claude" removes only the link, not the config.

When registering the server manually on Windows, use uv's absolute path (e.g. C:\Users\<you>\.local\bin\uv.exe). Packaged apps do not reliably inherit your shell PATH, so a bare uv may fail to launch.

Verifying the server is actually loaded

Confirm the client spawned it by checking process parentage:

Get-CimInstance Win32_Process -Filter "Name='uv.exe'" | ForEach-Object {
  $p = Get-CimInstance Win32_Process -Filter "ProcessId=$($_.ParentProcessId)"
  "$($_.ProcessId) <- $($p.Name)"
}

A uv.exe whose parent is Claude.exe means the server is running. Note that some Claude Desktop builds do not write per-server logs to logs\, so an empty log folder is not evidence of failure.

Project layout

server/weather.py     the MCP server: tool, resource, and NWS client
main.py               placeholder entrypoint
.mcp.json             Claude Code server config
.cursor/mcp.json      Cursor server config
pyproject.toml        dependencies (httpx, mcp[cli])

Notes

• get_alerts covers US states only, since NWS is a US agency.

• Requests carry a User-Agent header, which the NWS API requires.

• Network and HTTP errors are swallowed and surface as a friendly "unable to fetch" message rather than a traceback.