.. _gatt_dm_readme:

GATT Discovery Manager
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The GATT Discovery Manager handles service discovery on GATT servers.

When a client connects to a peer device that has a desired server, service discovery is necessary to ensure that the client interacts with the server's characteristics using the correct attributes handles.
Service discovery is also important because Bluetooth LE advertising does not mandate that all services are advertised.
To actually know if a service is present on a peer device, you must perform a service discovery.

The GATT Discovery Manager simplifies the usage of :ref:`Zephyr <bluetooth_api>`'s :cpp:func:`bt_gatt_discover` function by processing the data using predefined filters.

The GATT Discovery Manager is used, for example, in the :ref:`bluetooth_central_hids` sample.

Limitations
***********

* Only one discovery procedure can be running at the same time.

API documentation
*****************

.. doxygengroup:: bt_gatt_dm
   :project: nrf
   :members: