-struct command* register_command(struct command_context *context,
- struct command *parent, char *name, command_handler_t handler,
- enum command_mode mode, char *help);
+/**
+ * Register a command @c handler that can be called from scripts during
+ * the execution @c mode specified.
+ *
+ * If @c parent is non-NULL, the new command will be registered as a
+ * sub-command under it; otherwise, it will be available as a top-level
+ * command.
+ *
+ * A conventioal format should be used for help strings, to provide both
+ * usage and basic information:
+ * @code
+ * "@<options@> ... - some explanation text"
+ * @endcode
+ *
+ * @param cmd_ctx The command_context in which to register the command.
+ * @param parent Register this command as a child of this, or NULL to
+ * register a top-level command.
+ * @param name The name of the command to register, which must not have
+ * been registered previously.
+ * @param handler The callback function that will be called. If NULL,
+ * then the command serves as a placeholder for its children or a script.
+ * @param mode The command mode(s) in which this command may be run.
+ * @param help The help text that will be displayed to the user.
+ * @returns The new command, if successful; otherwise, NULL.
+ */
+struct command* register_command(struct command_context *cmd_ctx,
+ struct command *parent, const char *name,
+ command_handler_t handler, enum command_mode mode,
+ const char *help);