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SMS MCP server: Let your AI agents send SMS and voice messages
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REST · HTTP · MAIL · SOAP · KANNEL SMS Gateway

SMS Gateway
REST, SMPP, and Mail2SMS API

Integrate SMS sending into your own application via our SMS gateway. We offer a reliable, fast REST API for worldwide SMS delivery. It doesn't get any simpler.

  • No base fee for SMS sending
  • No setup fee
  • Servers in Germany
AVAILABILITY
99.9%
Germany from
1cents / SMS

LOX24 SMS API at a glance

api.lox24.eu

01 · SAMPLE REQUEST

POST https://api.lox24.eu/sms
X-LOX24-AUTH-TOKEN: <API-Key>
Content-Type: application/json

{
  "sender_id":    "LOX24",
  "phone":        "+49151…",
  "text":         "Your code: 442 981",
  "service_code": "direct",
  "delivery_at":  0,
  "is_unicode":   true
}

02 · TECHNICAL SPECS

ENDPOINTS
POST /sms · POST /bulks · GET /sms
PROTOCOL & SECURITY
REST · JSON · TLS-encrypted · IP blocking
FEATURES
Scheduled sending · Unicode · delivery reports via callback · Voice message
THROUGHPUT & COVERAGE
10 SMS/second · 880 networks worldwide
OTHER ACCESS OPTIONS
Mail2SMS · SMPP (Kannel) · MCP server

03 · HTTP STATUS CODES

201
SMS accepted
400
Invalid input
401
API key invalid or inactive
402
Insufficient balance
403
Account not yet activated
404
Resource not found
5xx
System error – contact LOX24 support
FULL API DOCUMENTATION
Various interfaces
rest
http
mail2sms
soap
kannel smpp
curl
php
python
rest
http
mail2sms
soap
kannel smpp
curl
php
python
Interfaces

Ways to access the gateway

 

Whether you're a developer, a marketing team, or an AI agent: the LOX24 SMS gateway can be connected in whatever way suits your application. All access options use the same infrastructure: the same 880 networks, the same servers in Europe, and the same price list.

 

REST API

The REST API is the direct route into your software. You send individual SMS as JSON to api.lox24.eu, receive delivery reports via callback, and control the sender, send time, and character set for each message. Code examples are available for curl, PHP, Python, Java, Go, C#, and JavaScript.

Discovering the REST API
SMS-MO

Bulk SMS API

With the bulk SMS API, you can submit several thousand recipients in a single request, as a list of numbers or as a saved distribution group. Placeholders such as %vorname% personalize each message automatically.

Discovering the mass SMS API
Single

Mail2SMS

With Mail2SMS, you send SMS as a regular email, no programming required. The LOX24 SMS gateway converts the message and delivers it as an SMS. This is ideal for monitoring systems, printers, NAS devices, or older software that can only send emails.

Discover Mail2SMS
Mail

SMPP via Kannel

For existing telecommunications and messaging systems, LOX24 supports sending via Kannel. The connection runs through a variant with integrated SSL, encrypted and stable.

Read the Kannel manual
Personal

Web interface

In the LOX24 web interface, you can send individual or bulk SMS directly in your browser. You can import numbers as CSV, save templates, and read replies in your inbox. You'll also find delivery reports and the itemized connection record there.

Discover the web interface
SMPP

MCP server for AI agents

Through the LOX24 MCP server, AI assistants such as Claude, Cursor, or Windsurf can send SMS and voice messages, read incoming SMS, and check your balance. Setup takes just a few minutes, and all you need is an API key.

MCP servers discover
SMPP
GDPR-compliant SMS gateway

Reliable SMS interface

Your SMS should arrive, not disappear into thin air. We've made it our mission to ensure your SMS reaches the recipient within seconds. As a leading provider, we offer the most reliable SMS gateway API and extremely attractive prices.

RegistrationAPI description
Our philosophy

SMS Gateway Technical Features

An SMS gateway has to do more than just relay messages. It has to absorb load peaks, prevent abuse, and tell your application at any time what happened to each individual SMS.

Throughput & Availability

By default, the LOX24 SMS gateway processes 10 SMS per second; we can set up higher throughput on request. The systems are designed with multiple redundancies and achieve 99.9% availability. Proactive monitoring detects problems with carriers and switches to alternative routes before your delivery suffers.

Security

Every request to the LOX24 API is TLS-encrypted and authenticated via an API key in the header X-LOX24-AUTH-TOKEN With an IP restriction, you specify that only your application's servers may send SMS. A stolen API key is therefore worthless to attackers.

 

Filters & spending limit

With the LOX24 SMS gateway filters, you set daily limits, permitted destination countries, and maximum amounts. If an error in your software triggers an endless loop, or an attacker tries to trigger SMS in bulk through your login form (SMS pumping), sending stops automatically.

Delivery Reports via Callback

For every SMS, LOX24 reports the delivery status to your application via callback: delivered, in transit, or undeliverable. Using the field callback_data you attach your own identifier to each message, such as an order or ticket number, and match the report directly. In the web interface, the itemized connection record with delivery rate is also available.

 

Scheduled Sending & Unicode

With delivery_at you can schedule SMS to the exact second, for example appointment reminders the day before at 6 p.m. With is_unicode you can send emojis and special characters. The gateway automatically splits texts over 160 characters into multiple message parts, which appear to the recipient as a single message. With voice_lang the same message is read aloud as a voice call, including to landline numbers.

 

Privacy

The LOX24 SMS gateway runs exclusively on servers in Europe and is subject to telecommunications secrecy under § 3 TDDDG. Phone numbers and SMS content are used only for delivery.

Quick Start

Your First SMS via the LOX24 SMS Gateway in Three Steps

 

Connecting to the LOX24 SMS gateway usually takes only a few minutes. You need an account, an API key, and a single HTTP request.

Register for free Create a LOX24 account. You'll instantly receive 50 cents in starting credit!
01 · Prepare

Create an API Key

In your customer account, create an API key under "API Settings". Optionally, restrict access to your servers with an IP restriction and set a cost limit.
02 · Send

Send Your First SMS

Send a JSON request to https://api.lox24.eu/sms and pass the API key in the header X-LOX24-AUTH-TOKEN. On success, the API responds with 201 Created.
curl -X POST https://api.lox24.eu/sms \
  -H 'X-LOX24-AUTH-TOKEN: <API-Key>' \
  -H 'Content-Type: application/json' \
  -d '{
    "sender_id": "YourShop",
    "phone": "+49151…",
    "text": "Hello!",
    "service_code": "direct"
  }'
03 · Success

Receive the Delivery Report

Set up a callback URL, and LOX24 notifies your application whether each SMS was delivered. Alternatively, you can see all deliveries in the web interface.
PER SMS
from 7cents
NO EXTRA SOFTWARE
No.
Two-way SMS dialogs

Receive SMS: Virtual Number and Inbound API

With our SMS interface, you can optionally receive inbound SMS as well. For a monthly base fee of €29, we set up a dedicated number for you. We can deliver all messages received on this number to you via HTTP request or email.

29 €

Monthly base fee, dedicated number

HTTP / Email

Delivery via HTTP request or email

Details in the SMS API documentation
Bulk SMS API

Thousands of SMS at once with a single HTTP request

Our SMS gateway can process not just individual SMS; you can also send us several thousand SMS at once with a single HTTP request. This saves resources and speeds up SMS delivery. You can either send us all recipients or work with existing distribution groups.

RegistrationBulk SMS API details
FAQ

Questions and answers about the SMS gateway

An SMS gateway is an interface between software and the mobile network. Applications such as online stores, CRM systems, or login services use it to send SMS automatically, without needing their own contracts with network operators. The LOX24 SMS gateway accepts messages via API, email, or web interface and delivers them to 880 mobile networks worldwide, with servers located exclusively in Europe.

 

The most important interface is the REST API with JSON, for single SMS (POST /sms) and for bulk sending (POST /bulks). Without any programming, you can send SMS by email (Mail2SMS) or via the web interface. For existing systems, LOX24 also supports SMPP via Kannel with SSL. AI agents such as Claude or Cursor connect to the gateway through the LOX24 MCP server.

You create an API key in your LOX24 customer account and send it in the header X-LOX24-AUTH-TOKEN with every request. The connection to api.lox24.eu is TLS-encrypted. You can also restrict access to your application's servers using IP blocking.

 

By default, the LOX24 SMS gateway processes 10 SMS per second per account; we can set up higher throughput on request. For large campaigns, there is the bulk SMS API: you submit several thousand recipients in a single request, and LOX24 handles the distribution.

 

An SMS has 160 characters in the standard character set (GSM-7), which includes German umlauts. For emojis and special characters, set is_unicode on true. Then 70 characters are available per SMS. Longer texts are automatically split into multiple SMS and displayed to the recipient as a single message. Billing is per message part.

For every SMS, LOX24 provides a free delivery report. You can have it sent to your application via callback (webhook). With the field callback_data you attach your own identifier to each SMS, such as an order number, which is returned in the delivery report. In the web interface, you can see all deliveries in the itemized record, including the delivery rate.

Yes. With the field delivery_at you specify a Unix timestamp, and the LOX24 SMS Gateway sends the message at that time. This is well suited for appointment reminders the day before or campaigns at a fixed time.

 

The LOX24 SMS gateway offers filters and cost limits. They let you set how many messages may be sent per day and to which countries. If there is an attack or an error in your application, such as an infinite loop, sending stops automatically. Together with IP blocking, this prevents costly SMS fraud such as SMS pumping.

 

You pay per SMS sent, starting at 1 cent depending on the destination country, and starting at 7 cents for Germany. There is no base fee, no setup fee, and no contract term for sending. Billing works through prepaid credit, and you receive 50 cents free after registration to try the service. Only a dedicated phone number for receiving SMS costs €29 per month.

 

Yes. All servers of the LOX24 SMS gateway are located exclusively in Europe. As a telecommunications provider registered with the Federal Network Agency (Bundesnetzagentur), LOX24 is subject to telecommunications secrecy under § 3 TDDDG, so the content of your SMS is legally protected. LOX24 provides a data processing agreement (DPA) on request.

 

Test the SMS gateway now!

Integrate our SMS gateway into your application today. With 50 cents of free credit, you can test the SMS gateway with no obligation.
  • No contract term
  • Cancel anytime without a notice period
  • Servers exclusively in Europe
Sign up for free now!

Test the SMS gateway now!

Connected in 5 minutes: create an account, generate an API key, send your first SMS – with 50 cents of starting credit.

50 CENTS FREE CREDIT
NO SETUP FEE
SERVERS IN EUROPE
UNCOMPROMISING SECURITY