There are different options for creating clients for nymea.
The first option is to access the raw JSONRPC API. This is the main way of interacting with nymea from a client perspective. Please refer to the RAW JSONRPC API documentation for a detailed documentation on all the available methods.
If writing a C++ or Qt/QML client application, nymea:app’s internal library can be used to have a complete wrapper of the JSONRPC API. Please refer to the nymea:app library documentation for instructions on how to get started.
For python developers there is nymea-cli providing examples how to interact with nymea. Please refer to the nymea:cli documentation.