How to use the Android MCP SMS Server in Claude Cowork

This guide explains how to connect the Ozeki Android SMS Gateway MCP server to Claude Cowork, enabling the AI assistant to send SMS messages directly from your Android phone. By following this tutorial, you will learn how to install the Ozeki Android SMS Gateway app, enable its built-in MCP server, register the MCP endpoint in Claude Cowork, and verify that everything is working by sending a test message.

Claude Cowork SMS MCP Server poster

Solution: How to send SMS from Claude Cowork

Claude Cowork is connected to the Ozeki Android SMS MCP Server through the MCP protocol, where Claude Cowork is the MCP client and the Android phone is the MCP server. The Android phone is connected to the SMS service provider through a wireless mobile network connection. When an SMS is sent, it first travels from Claude Cowork to the Android phone through the MCP protocol, and the Android phone forwards it to the SMS service provider, which delivers it to the recipient's mobile phone.

Send SMS from Claude Cowork
Send SMS from Claude Cowork

What is Claude Cowork?

Claude Cowork is a desktop productivity application developed by Anthropic that brings Claude AI directly to your Windows desktop. It allows you to automate file and task management workflows using plain language instructions, without requiring any coding knowledge. The application supports MCP servers, enabling it to be extended with external tools such as SMS messaging, database access, and more, making it a powerful automation platform for everyday computer tasks.

What is Claude Cowork
What is Claude Cowork

What is an Android SMS MCP Server?

An Android SMS MCP Server is a Model Context Protocol server that runs directly on an Android smartphone and exposes SMS functionality — such as sending text messages and querying SIM subscriptions — as structured tools that any MCP-compatible AI client can call. Once installed and configured, the AI client can send real SMS messages through the phone's SIM card to any phone number, with a single tool call.

What is an Android SMS MCP Server
What is an Android SMS MCP Server

Download Ozeki Android SMS Gateway

To use this solution you need to install the Android app on your Android phone.

Steps to follow

You will need Claude Cowork installed on your system, you can download it from here: https://claude.com/product/cowork

  1. Install Ozeki Android SMS Gateway
  2. Enable MCP SMS Server
  3. Claude Cowork SMS MCP Server Config
  4. Add the SMS MCP Server config to Claude Cowork
  5. Send a test SMS
  6. Check the SMS in the SMS Gateway logs

Step 1 - Install Ozeki Android SMS Gateway

For a full tutorial on installing the Ozeki Android SMS Gateway, check out our How to install Android SMS Client and Enable Ozeki SMS Client permissions guides.

Before you can use the MCP SMS Server, you need to install the Ozeki SMS Client on your Android device. The app will serve as the local SMS gateway that Claude Cowork connects to over your Wi-Fi network. Make sure both devices are on the same local network, as this is required for the HTTP connection to work.

Step 2 - Enable MCP SMS Server

For a full tutorial on enabling the MCP server in the Android app, check out our Android MCP SMS Server configuration guide.

Open the Ozeki SMS Client app on your Android device and tap the MCP tab in the bottom navigation bar. Tap the toggle switch to start the MCP server and grant any permission requests that appear, including access to SMS messages. The toggle will switch from "Stopped" to "Running" and the API endpoint URL will appear below. Copy this URL, as you will need it when configuring Claude Cowork in the next step.

Step 3 - Claude Cowork SMS MCP Server Config

# Open: Settings -> Developer -> Edit Config -> claude_desktop_config.json
# Replace {address} with your Ozeki Android SMS Gateway address
"mcpServers": {
  "ozeki-sms": {
    "command": "uvx",
    "args": [
      "mcp-proxy",
      "--transport", "streamablehttp",
      "http://{address}:9531/mcp"
    ]
  }
},

Example prompt

Send an SMS to +36301234567, the message should be "Hello from Claude Cowork".

Step 4 - Add the SMS MCP Server config to Claude Cowork

The following video shows how to add the Android SMS MCP server to Claude Cowork step-by-step.

Open Claude and navigate to Settings. Select the Developer section and click Edit Config to open the configuration directory in File Explorer (Figure 1).

Click Edit Config in Developer menu in Settings
Figure 1 - Click Edit Config in the Developer menu in Settings

In the configuration directory, locate and open the claude_desktop_config.json file in a text editor such as Notepad or Visual Studio Code. This file stores all MCP server registrations for Claude Cowork (Figure 2).

Open claude_desktop_config.json in a file editor
Figure 2 - Open the claude_desktop_config.json file in a text editor

Add the Ozeki Android SMS MCP server entry inside the mcpServers block as shown below. Replace {address} with the IP address shown in the Ozeki SMS Client app on your Android device. The entry uses uvx and mcp-proxy to bridge the streamable HTTP transport used by the Android gateway. Save the file after making the changes (Figure 3).

"mcpServers": {
  "ozeki-sms": {
    "command": "uvx",
    "args": [
      "mcp-proxy",
      "--transport", "streamablehttp",
      "http://{address}:9531/mcp"
    ]
  }
},

Add Ozeki SMS MCP server to config
Figure 3 - Add the Ozeki SMS MCP server entry to the config

Restart Claude to apply the updated configuration. Claude Cowork will reload the config file on startup and attempt to connect to the registered MCP servers (Figure 4).

Restart Claude Cowork
Figure 4 - Restart Claude Cowork to apply the configuration

After Claude restarts, open the Connectors panel and verify that ozeki-sms appears with a connected status. This confirms that the application has successfully reached the Android gateway and the MCP tools are available (Figure 5).

Verify server connection from Connectors
Figure 5 - Verify the server connection from the Connectors panel

Step 5 - Send a test SMS

The following video shows how to send an SMS message from Claude Cowork using the Ozeki Android SMS MCP server step-by-step.

Type a plain language instruction in the Claude Cowork chat prompt asking the AI to send an SMS to a specific phone number. The assistant will call the Send SMS tool and process the request (Figure 6).

Send an SMS to +36301234567, the message should be "Hello from Claude Cowork".

Instruct assistant to send an SMS
Figure 6 - Instruct the assistant to send an SMS message

Claude Cowork may prompt you to allow the tool use before proceeding. This is a security confirmation to ensure you are aware that an external tool is being called on your behalf. Confirm the action to allow the AI to send the SMS (Figure 7).

Allow tool use if prompted
Figure 7 - Allow the tool use if prompted

You will see the result of the Send SMS tool call in the chat window. A successful response confirms that the message has been passed to the Android gateway and queued for delivery (Figure 8).

Send SMS tool result
Figure 8 - Send SMS tool result

Step 6 - Check the SMS in the SMS Gateway logs

The following video shows how to check the gateway logs in the Ozeki SMS Client app step-by-step. This allows you to confirm that the SMS request was received and processed successfully by the Android gateway.

Open the Ozeki SMS Client app on your Android device and navigate to the Settings tab in the bottom navigation bar to access the application settings. Tap the Log option to view the request and response history (Figure 9).

Open logs in gateway settings

Figure 9 - Open the logs in the gateway settings

Select the MCP tab to show only MCP-related activity. Here you will see the incoming tool call requests from Claude Cowork and the responses sent back, allowing you to confirm that the SMS was dispatched successfully (Figure 10).

Select MCP tab and view logs

Figure 10 - Select the MCP tab to view the MCP activity logs

Summary

You have successfully configured the Ozeki Android SMS Gateway MCP server with Claude Cowork. Your Android device is now acting as a local SMS gateway, enabling text messages to be sent to any phone number using plain language prompts over your local network. All SMS traffic is routed through the device's mobile connection, with no cloud messaging API or third-party service required.


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