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PopNx MCPMCP servers for people who use AI · explained in plain words

Alphorn

by alphorn-devversion 0.1.1i★ –iRuns on your computer
Registry nameio.github.alphorn-dev/mcp

Install

Overview

Description from the maker (original English)

Let AI agents notify you on Slack, Telegram, email, SMS, or push via an Alphorn webhook.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs on your computer
  • Transport: stdio
  • Category: Chat & email
  • You need to fill in: ALPHORN_WEBHOOK_URL, ALPHORN_API_KEY

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on your computer with your user’s permissions (files, network, apps).
  • You fill in yourself: ALPHORN_WEBHOOK_URL, ALPHORN_API_KEY

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

  • npmNode.js installed (for the npx command)

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "alphorn-dev": {
      "command": "npx",
      "args": [
        "-y",
        "@alphorn/mcp"
      ],
      "env": {
        "ALPHORN_WEBHOOK_URL": "your-value",
        "ALPHORN_API_KEY": "your-value"
      }
    }
  }
}

Run this in your terminal

claude mcp add alphorn-dev --env ALPHORN_WEBHOOK_URL=your-value --env ALPHORN_API_KEY=your-value -- npx -y @alphorn/mcp

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "alphorn-dev": {
      "command": "npx",
      "args": [
        "-y",
        "@alphorn/mcp"
      ],
      "env": {
        "ALPHORN_WEBHOOK_URL": "your-value",
        "ALPHORN_API_KEY": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "alphorn-dev": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@alphorn/mcp"
      ],
      "env": {
        "ALPHORN_WEBHOOK_URL": "your-value",
        "ALPHORN_API_KEY": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

  • ALPHORN_WEBHOOK_URL secret required env
    Webhook Endpoint URL, e.g. https://app.alphorn.dev/n/V1StGXR8_Z5jdHi6B-myT
  • ALPHORN_API_KEY secret env
    Webhook API key (alp_...), if the webhook requires one

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 6, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified with the GitHub account alphorn-dev, which owns the repo

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • – Not applicable

    Endpoint responds

    This one runs on your computer; there is no internet endpoint

  • – Not applicable

    Sign-in with OAuth

    Runs on your computer and uses local settings instead

  • … Not checked yet

    No hidden instructions in tool descriptions

    Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Chat & emaili

  • More stars than 0% of the other 1767 servers in this category
  • Published to the registry more recently than 51% of the other 1767 servers in this category
  • Basic checks equal to or better than 100% of the other 1767 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Alphorn safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: ALPHORN_WEBHOOK_URL, ALPHORN_API_KEY

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (0.1.1) reached the registry 25 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: Vexa, emailmd, MCP WhatsApp Cloud

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Vexa

by Vexa-ai

Meeting bot and transcripts for Google Meet, Teams and Zoom. Live or after, speakers labelled.

Runs in the cloud★ 2,949Apache-2.0Updated 2 months ago
Install

emailmd

by anypost

Render markdown into email-safe HTML, lint drafts for deliverability problems, and preview emails.

Computer or cloud★ 1,385MITUpdated 31 days ago
Install

MCP server for WhatsApp Cloud API (Meta) — messages, media, and templates via Graph API

Runs on your computer★ 277MITUpdated 5 months ago
Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

Alphorn MCP Server

MCP server for Alphorn, the open-source notification router. It gives AI agents (Claude Code, Claude Desktop, Cursor, Codex, and any other MCP client) a send_notification tool, so an agent can tell you when a task finishes, fails, or needs your decision, on whatever channel you configured in Alphorn: Slack, Telegram, Discord, email, SMS, push, and more.

Works with the hosted service at app.alphorn.dev and with self-hosted Alphorn.

Setup

  1. Create a webhook in Alphorn and copy its Endpoint URL, plus its API key if you switched on Require API key (docs).
  2. Add the server to your MCP client with two environment variables:
VariableValue
ALPHORN_WEBHOOK_URLEndpoint URL, e.g. https://app.alphorn.dev/n/V1StGXR8_Z5jdHi6B-myT
ALPHORN_API_KEYWebhook API key (alp_...). Leave unset if the webhook does not require one.
Claude Code
claude mcp add alphorn -s user \

-e ALPHORN_WEBHOOK_URL=https://app.alphorn.dev/n/V1StGXR8_Z5jdHi6B-myT \ -e ALPHORN_API_KEY=alp_... \ -- npx -y @alphorn/mcp

Claude Desktop (one-click bundle)

Download alphorn.mcpb from the latest release and open it. Claude Desktop asks for the Endpoint URL and API key.

Claude Desktop, Cursor, and other JSON-configured clients

Add to claude_desktop_config.json, ~/.cursor/mcp.json, or your client's MCP config:

{

"mcpServers": { "alphorn": { "command": "npx", "args": ["-y", "@alphorn/mcp"], "env": { "ALPHORN_WEBHOOK_URL": "https://app.alphorn.dev/n/V1StGXR8_Z5jdHi6B-myT", "ALPHORN_API_KEY": "alp_..." } } } }

OpenAI Codex CLI
# ~/.codex/config.toml

[mcp_servers.alphorn] command = "npx" args = ["-y", "@alphorn/mcp"] env = { ALPHORN_WEBHOOK_URL = "https://app.alphorn.dev/n/V1StGXR8_Z5jdHi6B-myT", ALPHORN_API_KEY = "alp_..." }

Tool

send_notification
ArgumentTypeRequiredDescription
messagestringyesWhat happened and what the agent needs from you (max 4,000 characters)
titlestringnoShort title, e.g. my-app - tests passing (max 200 characters)
priorityinteger 1-5no2 = finished, 3 = needs input, 4 = blocked or failed, 5 = urgent
tagsstring[]noTags to filter and route on in Alphorn, e.g. ["ai-agent", "completed"]

The tool wraps Alphorn's send endpoint. For direct HTTP use, see the API reference and the OpenAPI 3.1 specification.

Use Alphorn's filters to decide where each notification goes, for example SMS only for priority 4 and above.

Development

pnpm install

pnpm test # builds, then runs the tests against a local fake endpoint

Releasing
  1. Bump version in package.json, server.json (both fields), manifest.json, and VERSION in src/server.ts.
  2. npm publish --access public
  3. Push a v tag (or run the Publish to MCP Registry workflow): it publishes server.json to the MCP Registry via GitHub OIDC
  4. pnpm bundle, then attach alphorn.mcpb to a GitHub release

License

AGPL-3.0-or-later

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