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doc/nrf/protocols/matter/end_product/custom_cluster.rst

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+.. _ug_matter_custom_cluster:
+
+Custom Matter cluster
+#####################
+
+.. contents::
+   :local:
+   :depth: 2
+
+This document serves as a comprehensive guide for developers looking to understand and utilize the Matter Interface Definition Language (IDL) to create custom Matter clusters.
+The primary goal is to explain the fundamentals of Matter IDL, and provide a step-by-step tutorial on how to define and implement a new user-specific Matter cluster.
+Additionally, it will cover the process of integrating the newly created cluster into the common Matter database, ensuring seamless interoperability and functionality within the Matter ecosystem.
+
+Matter IDL
+**********
+
+Matter IDL is a language used to define the interfaces and data structures for Matter devices.
+It allows developers to describe the capabilities and attributes of a device in a standardized way, which can then be used to generate code and documentation for different platforms and languages.
+
+The IDL file typically includes definitions for:
+- Clusters: Groups of attributes and commands that represent a specific functionality.
+- Attributes: Data points that can be read or written.
+- Commands: Actions that can be invoked on the device.
+
+A Matter IDL file is defined as a :ref:`Lark <https://lark-parser.readthedocs.io/en/latest/index.html>` language grammar, which is a Python library for parsing context-free grammars.
+Thanks to that the IDL file is intended for human readability as well as machine parsing.
+
+How to create a custom cluster
+******************************
+
+To create a custom cluster and add it to the Matter database you need to create a Matter IDL file, use the generator to covert it to the XML format and then append it to existing Matter database.
+The guide has been divided into the three steps to make it easier to follow.
+In this guide the simple cluster will be created with one attribute and one command.
+
+Create a Matter IDL file
+========================
+
+To create Matter IDL file you need to define the cluster, attributes, and commands.
+You can follow a guidance from the :ref:`Matter IDL documentation <>` to see an example on how to write a Matter IDL file.
+
+The following example shows how to create a custom cluster with one attribute and one command.
+Each step is described as a comment so you can copy it directly to your :file:`.matter` file and use for the next steps.
+