$ ./result/bin/otbr-agent --help
Usage: ./result/bin/otbr-agent [-I interfaceName] [-B backboneIfName] [-d DEBUG_LEVEL] [-v] [--auto-attach[=0/1]] RADIO_URL [RADIO_URL]
    --auto-attach defaults to 1
RadioURL:
    forkpty-arg[=argument string]  Command line arguments for subprocess, can be repeated.
    spinel+hdlc+uart://${PATH_TO_UART_DEVICE}?${Parameters} for real uart device
    spinel+hdlc+forkpty://${PATH_TO_UART_DEVICE}?${Parameters} for forking a pty subprocess.
Parameters:
    uart-parity[=even|odd]         Uart parity config, optional.
    uart-stop[=number-of-bits]     Uart stop bit, default is 1.
    uart-baudrate[=baudrate]       Uart baud rate, default is 115200.
    uart-flow-control              Enable flow control, disabled by default.
    uart-reset                     Reset connection after hard resetting RCP(USB CDC ACM).
    region[=region-code]          Set the radio's region code. The region code must be an
                                  ISO 3166 alpha-2 code.
    cca-threshold[=dbm]           Set the radio's CCA ED threshold in dBm measured at antenna connector.
    enable-coex[=1|0]             If not specified, RCP coex operates with its default configuration.
                                  Disable coex with 0, and enable it with other values.
    fem-lnagain[=dbm]             Set the Rx LNA gain in dBm of the external FEM.
    no-reset                      Do not send Spinel reset command to RCP on initialization.
    skip-rcp-compatibility-check  Skip checking RCP API version and capabilities during initialization.