--help

Passing --help (short form: -h) prints the CLI usage text to standard output. The output opens with a version-and-app-name header line and a usage synopsis, then an OPTIONS block listing every recognized flag drawn from the three internal config definition groups (miscellaneous options, transform options, and action options), and finally a "Print settings priorities" block that explains the three-level override order: command-line values beat settings loaded via --load_settings and --load_filaments, which in turn beat values embedded in the 3MF.

The flag is typed as a boolean option that defaults to false; no value is accepted alongside it. Its presence is recorded as an "action" and is dispatched in the same action-processing loop as flags like --slice or --export-3mf. In that loop, the help-print call has no subsequent break, return, or early-exit -- the loop simply advances to the next action. Combining --help with another action flag such as --slice is therefore syntactically legal, and both will be carried out: the help text prints first, and then the slice (or other requested action) proceeds normally.

--help is also triggered automatically in two other conditions: when the parser encounters an unknown or malformed option (in that case the parser writes its own error to standard error first, then prints the help text before aborting), and when the binary is built without GUI support and is invoked without any action flags. This second trigger fires whenever the action list is empty, which includes bare no-argument invocations as well as invocations that supply input files but no action flags. Both involuntary triggers invoke the same help-printing routine but the context differs -- the intended diagnostic use is different from a deliberate help request.

The extended print-option listings that once existed as --help-fff and --help-sla are commented out in the current source and are not registered as recognized flags. The --help output therefore covers only the CLI control flags themselves, not the hundreds of per-profile print settings (layer height, infill density, etc.) that can be passed on the command line. There is no flag currently available to enumerate those options programmatically.