How to send SMS through SMPP from ZeroClaw
This guide explains how to connect ZeroClaw to Ozeki SMS Gateway's built in SMS MCP server, enabling the AI assistant to send and receive SMS messages through your own on-premises SMS gateway. You will learn how to install Ozeki SMS Gateway, create an MCP user account, generate an API key, register the MCP endpoint in ZeroClaw, and verify the setup by sending a test message.
Solution: How to send SMS from ZeroClaw
ZeroClaw connects to the SMPP SMS MCP Server through the MCP protocol, where ZeroClaw acts as the MCP client and Ozeki SMS Gateway acts as the MCP server. Ozeki SMS Gateway is installed on your local machine or server and connects to the SMS service provider over the internet using an SMPP client connection. When an SMS is sent, it first travels from ZeroClaw to the Ozeki SMS Gateway as an MCP tool call, and the gateway forwards it to the SMS service provider over SMPP, which delivers it to the recipient's mobile phone.
What is ZeroClaw?
ZeroClaw is an AI agent platform that allows you to build and run autonomous workflows directly from your desktop. It features a daemon-based architecture with a web dashboard for managing agents and tools, and supports MCP servers through its TOML-based configuration, enabling it to be extended with external capabilities such as SMS messaging, database access, and more.
What is an SMPP SMS MCP Server?
An SMPP SMS MCP Server is a standardized software bridge that uses the Model Context Protocol to connect AI assistants (like Claude) to an SMS gateway system such as Ozeki SMS Gateway, which in turn delivers messages to the mobile network over an SMPP client connection. It exposes tools like "send_message" or "list_incomings" that an AI can autonomously call to perform real-world texting tasks without custom coding. This allows users to simply ask an AI to "send John a reminder text" and have the AI securely execute the action through the server. The SMS MCP Server built into Ozeki SMS Gateway also makes receiving SMS messages possible.
Download Ozeki SMS Gateway
To use this solution you need to install the SMS Gateway on your system.
Download the software: SMS Gateway
https://ozeki-sms-gateway.com/p_727-download-sms-gateway.html
Steps to follow
You will need ZeroClaw installed on your system, you can download it from here: https://github.com/zeroclaw-labs/zeroclaw
- Install Ozeki SMS Gateway
- Setup the SMPP SMS connection
- Create an MCP user account
- ZeroClaw SMS MCP Server Config
- Add the SMS MCP Server config to ZeroClaw
- Send a test SMS
- Check the SMS in the SMS Gateway logs
Install Ozeki SMS Gateway
For a full tutorial on installing Ozeki SMS Gateway, check out our How to install Ozeki SMS Gateway on Windows guide.
Before you can use the SMS MCP Server, you need to install Ozeki SMS Gateway on your Windows machine or server. Download the installer zip file from the website, extract it, and run the executable to complete the installation. Once installed, the gateway will start automatically and its web-based management interface will be accessible from your browser.
Setup the SMPP SMS connection
For a full tutorial on setting up an SMPP Client connection, check out our SMPP Client Connection guide.
Before creating the MCP user, you need to connect Ozeki SMS Gateway to the mobile network by setting up an SMPP client. In the Connections panel, select Add new connection, and install a new SMPP client connection. Enter the host, port, and credentials provided by your SMS service provider, then save and activate the connection to bring the gateway online.
Create an MCP user account
For a full tutorial on creating an MCP User, check out our Create an MCP User guide.
Click Add new user/application, and select the MCP user type from the list. Enter a username and password for the account, then open the Advanced tab to generate an API key. Copy this key and store it in a safe location, as you will need it in the next steps.
ZeroClaw MCP server configuration
# Configuration file location:
%USERPROFILE%\.zeroclaw\config.toml
# Add the following block to config.toml
# Replace {address} with your Ozeki SMS Gateway host IP or hostname
# Replace ozk-abc123 with the API key generated for your MCP user account
[mcp]
[[mcp.servers]]
name = "ozeki-sms-mcp"
transport = "http"
url = "http://{address}:9529/mcp"
headers = { "Authorization" = "Bearer ozk-abc123" }
Example prompt
Send an SMS to +36301234567, the message should be "Hello from ZeroClaw".
Add the SMS MCP Server config to ZeroClaw
The following video shows how to add the Ozeki SMPP SMS MCP Server to ZeroClaw step-by-step.
Navigate to the ZeroClaw configuration directory at
%USERPROFILE%\.zeroclaw\ using File Explorer. You can open this
folder quickly by typing %USERPROFILE%\.zeroclaw directly into the
File Explorer address bar and pressing Enter (Figure 1).
Open the config.toml file in a text editor such as Notepad or
Visual Studio Code. This file stores all ZeroClaw configuration, including any
MCP servers (Figure 2).
Add the Ozeki SMS MCP server entry to the [mcp] block as shown
below. Replace {address} with the IP address or hostname of your
Ozeki SMS Gateway installation, and replace ozk-abc123 with the API
key you generated for your MCP user account. Save the file after making the
changes (Figure 3).
[mcp]
[[mcp.servers]]
name = "ozeki-sms-mcp"
transport = "http"
url = "http://{address}:9529/mcp"
headers = { "Authorization" = "Bearer ozk-abc123" }
Open the ZeroClaw dashboard and click Reload daemon to apply the updated configuration. The daemon will restart and connect to all MCP servers listed in the config file (Figure 4).
Navigate to the Tools section in the dashboard and verify that the SMS tools exposed by the Ozeki SMS MCP Server are listed. This confirms that ZeroClaw has successfully connected to your gateway (Figure 5).
Send a test SMS
The following video shows how to send an SMS message from ZeroClaw using the Ozeki SMPP SMS MCP server step-by-step.
Open the ZeroClaw dashboard and click the Open chat button corresponding to your configured AI agent (Figure 6).
Type a plain language instruction in the chat prompt asking the agent to send an SMS to a specific phone number. The agent will interpret the request and call the appropriate MCP tool to deliver the message (Figure 7).
Send an SMS to +36301234567, the message should be "Hello from ZeroClaw".
ZeroClaw may prompt you to approve 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 agent to send the SMS (Figure 8).
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 gateway and queued for delivery (Figure 9).
Check the SMS in the SMS Gateway logs
The following video shows how to check the SMS in the logs in Ozeki SMS Gateway step-by-step.
Open Ozeki SMS Gateway in your browser and navigate to the MCP user details page by clicking on the MCP user entry in the Users and applications panel (Figure 10).
In the MCP user event log, you should see an entry for the outgoing message, including the recipient number and message text, confirming that it was successfully processed by the gateway (Figure 11).
Summary
In this guide, you have learned how to connect ZeroClaw to Ozeki SMS Gateway's built-in SMS MCP Server and use it to send SMS messages directly from the chat interface. By installing the gateway, setting up an SMPP connection to the mobile network, creating an MCP user account, and registering the MCP endpoint in ZeroClaw, you now have a fully functional on-premises SMS integration that your locally hosted AI model can use to communicate with any mobile phone.