emelFM2 actions are primarily intended to be bound to UI items - a key-binding, a toolbar button and/or a menu item.

Any action may also be included in any customised command string.

Actions named like file.* apply to active-pane selected items.

An action which takes parameter(s) may need one or more of them to be expressed in multi-part form. In that case, the parts may be separated by comma- or space-characters. Note that this can cause problems if a single-part parameter or any part is intended to actually include comma- or space-character(s). A little care can ensure success. Don't supply a parameters string with an intended space before using a space to separate parts - use a comma to separate. Conversely, use a space to separate parts before a real comma. Note that many actions have some text and a space prepended internally.
 
In the following:
1. the Parameters column has either Y=parameter(s) are expected, O=parameter(s) optional, or N=no parameter
2. action names and parameter(s) are listed in their english form, but in general, they would be translated
(This document is best viewed in a monospace font.)

(ENGLISH) NAME		PARAMETER(S)	DESCRIPTION

bookmark.add			O	add dir to bookmarks. Parameter1: pane1 or pane2 = use the dir shown in that pane, or else a specific path (absolute or relative) or else none = use active pane dir; parameter2: (optional) top = add to top of list; child = add as child of clicked bookmark
bookmark.delete			O	remove dir from bookmarks. Parameter: a specific path or else use active pane directory;
children.<menu>			N	create menu of running child processes. Selection from that menu adds that child's pid to the command line (always prepended if <Ctrl> is pressed at the time of selection)
children.list			N	list in the output pane all the child processes of the running e2 instance
command.clear_history	N	remove all items from a command combobox's dropdown history-list
command.clear			N	clear the command line displayed text
command.del_history		N	remove current command-line contents from corresponding history-list
command.complete		O	complete command line. Parameter: none OR all = do all types, dirs = list all valid dirnames; files = all valid filenames; mounts = (un)mountable partitions for (u)mount command
command.focus			N	focus the command line
command.focus_toggle	N	toggle focus between command line and active pane
command.history			N	show in the output pane a list of completed commands and file-actions
command.insert_selection	O	insert at cursor position in command line, the selection in the currently focused widget. For a filelist, gets names of selected item(s), Arg may begin with "1" or "2" to get that pane's selection. For a filelist, arg may include "quote" or "escape" (as translated)
command.mkdir			N	open make-directory dialog
command.send			N	send command string to the last-run child process
command.quit			N	close the running e2 instance
configure.application	Y	open the configuration dialog. Parameter is the name of the page to show when starting
configure.bookmarks		N	open the bookmarks configuration dialog
configure.default		N	revert all configuration options to their respective default values
configure.filetypes		N	open the filetypes configuration dialog
configure.plugins		N	open the plugins configuration dialog
dialog.about			N	open help dialog (which includes a page with "about" info)
dialog.view				N	open (text) file view dialog (usually use file.view instead of this)
dirline.add_history		N	add contents of focused dirline to corresponding history (relevant when manually updating)
dirline.clear_history	N	remove all items from a dirline combobox's dropdown history-list
dirline.clear			N	clear the displayed text from the focused directory line
dirline.del_history		N	remove contents of focused dirline from corresponding history
dirline.focus_toggle	Y	toggle focus between a directory input line, and the last-focused filepane. Parameter = 1 or 2, for the corresponding dirline
file.copy_as			N	copy selected item(s) from active pane to inactive, each with new name
file.copy_merge			N	same as file.copy but merges, not replaces, any directories
file.copy_with_time		N	same as file.copy but preserves mtime and atime of copied files (not dirs, links, etc)
file.copy				N	copy selected item(s) from active pane to inactive
file.crypt				N	encrypt or decrypt selected items (this is supported in the crypt plugin)
file.delete				N	delete selected item(s) from active pane
file.edit				Y	open specified text file using the internal editor, or external editor if so configured
file.edit_again			Y	open specified text file using the internal edotor, with initial focus where it was last edited
file.find				N	open file-find dialog, to find named item in current pane
file.info				N	open information dialog for selected item(s) in active pane
file.move_as			N	move selected item(s) from active pane to inactive, each with new name
file.move				N	move selected item(s) from active pane to inactive
file.open_in_other		N	open selected directory in other pane
file.open				O	open first-slected item, or the named file if an argument is supplied, using the default (first) command for that file's filetype
file.open_with			O	open all selected item(s), or the named file if an argument is supplied, using a command entered or chosen via a dialog
file.open_withI			O	I is 1..6. Open all selected item(s), or the named file if an argument is supplied, using the Ith command for the filetype of the supplied file or the first selected item
file.owners				N	open owner/group dialog for selected item(s) in active pane
file.permissions		N	open permissions dialog for selected item(s) in active pane
file.rename				N	rename selected item(s) in active pane
file.symlink_as			N	link selected item(s) from active pane to inactive, each with new name
file.symlink			N	link selected item(s) from active pane to inactive
file.trash				N	move selected item(s) from active pane to trash
file.trashempty			N	delete all trashed items
file.view_at			Y	open specified text file using the internal viewer, with initial focus on a heading prescribed like [this]
file.view_again			Y	open specified text file using the internal viewer, with initial focus where it was last viewed
file.view				N	open first-selected text file using the internal or external viewer, according to the relevant config option
filelist.goto_top		O	display the top line of a filelist. Arg may be 1 or 2 or missing
filelist.goto_bottom	O	display the bottom line of a filelist
filelist.select_type	O	select all items which have the same extension as the first selected item
filelist.sortaccesssed	O	sort a filelist by item access time
filelist.sortchanged	O	sort a filelist by item change time
filelist.sortext		O	sort a filelist by item extension
filelist.sortgroup		O	sort a filelist by item group
filelist.sortmodified	O	sort a filelist by item modified time
filelist.sortname		O	sort a filelist by item name
filelist.sortpermission	O	sort a filelist by item pemissions
filelist.sortsize		O	sort a filelist by item size
filelist.sortuser		O	sort a filelist by item owner
filelist.toggle_select_all	O	toggle selection of all items in a flleiist
filelist.toggle_selected	O	toggle current selection-state of all items in a filelist
history.list			N	list in the output pane all prior commands and actions in the session
history.<menu>		O	show a menu of all directories in the forward/back history for the relevant filelist
option.set			Y	set config option from string Parameter = string like "option-name=option-value"
output.activate			N	open the filetype item (if any) whose path or name is under the pointer in the active output tab
output.adjust_ratio		Y	adjust height of output pane relative to the main window. Parameter = 0.0 (hidden) to 1.0 (full window), may have ",*" appended to decimal, to cause toggling. In that case, the arg string or at least the * char must be quoted to stop interpretation into a list of files
output.clear			N	clear all content from the output pane
output.focus			O	focus output pane or drop window. Paramter (if any) is tab-number string, 1...
output.goto_bottom		Y	scroll to and display the latest contents of the output pane
output.goto_top			Y	scroll to and display the initial contents of the output pane
output.help				Y	list help text in the output pane. Parameter: the binding category, panes etc
output.page_down		Y	scroll the output pane down by one pane-height
output.page_up			Y	scroll the output pane up by one pane-height
output.print			Y	display string in the output pane. Parameter = the string
output.scroll_down		Y	scroll the output pane down. Parameter = no of lines to scroll
output.scroll_up		Y	scroll the output pane up. Parameter = no of lines to scroll
output.expand			N	toggle output pane between full-window and last position TOGGLE ACTION
output.show 			N	toggle output pane between hidden and last position TOGGLE ACTION
pane1.<filters>			N 	show menu of filters for pane 1 TOGGLE ACTION
pane1.expand			N	toggle size of pane1 relative to pane1+pane2, full or partial TOGGLE ACTION
pane1.show_hidden		N	toggle display of hidden items in pane TOGGLE ACTION
pane2.<filters>			N 	show menu of filters for pane 2 TOGGLE ACTION
pane2.expand			N	toggle size of pane2 relative to pane1+pane2, full or partial TOGGLE ACTION
pane2.show_hidden		N	toggle display of hidden items in pane2 TOGGLE ACTION
pane.<bookmarks>		O 	show menu of bookmarks in a pane (both panes use the same bookmarks)
pane.<filters>			O 	show menu of filtering-options for a pane
pane.activate			O	make a pane active if it's not already so. Arg may be 1 or 2 or missing
pane.change				Y	display in a pane the dir specified in the latter part of the action argument e.g 1,~ First part may be 1 or 2 or missing
pane.clear_history		O	clear opened-directories history for pane(s). Arg may be 1 or 2 or 1,2 or "both"
pane.focus				O	focus a filelist (mainly for start of chained filelist keybings)
pane.go_back			O	display the dir that is before the current one in the corresponding history list. Arg may be 1 or 2 or missing
pane.go_forward			O	display the dir that is before the current one in the corresponding history list. Arg may be 1 or 2 or missing
pane.go_up				O	display in the parent of the dir currently shown there. Arg may be 1 or 2 or missing
pane.mirror				O	display in a pane the dir in the other pane. Arg may be 1 or 2 or missing
pane.open				O	display in a pane the dir chosen via a dialog
pane.tree 				O	open filesystem-directories-tree dialog for a pane
pane.show_menu			O	show filepane context menu. 2nd arg may be shift or ctrl
panes.adjust_ratio		Y	adjust size of pane1 relative to pane1+pane2. Parameter = 0.0 (hidden) to 1.0 (full size), may have ",*" appended to decimal, to cause toggling. In that case, the arg string or at least the * char must be quoted to stop interpretation into a list of files
panes.refresh			N	refresh contents of file panes if need be
panes.refreshresume		N	resume periodic checks for whether to update file panes
panes.refreshsuspend	N	cancel periodic checks for whether to update file panes
panes.switch			N	toggle the active file pane
panes.sync				N	change inactive filepane to be the same as active one
panes.toggle_direction	N	toggle between hoizontal and vertical layout for file panes
pending.clear			N	clear all queued commands and actions
pending.list			N	list in the output pane all queued commands and actions
toggle.fullscreen		N	toggle main window fullscreen on/off
trash.delete			N	delete all contents of trash directory, without confirmation
trash.open				N	display in the inactive file pane the trash dir for the active pane
<custom command>		Y	run a command (that is not one of the actions). Parameter is the command, with any command-parameters

FOR THE DEDICATED USER WHO WANTS IT ALL (and is prepared to un-comment some source-code before building) ...
file.untrash			O	reinstate selected item(s) in a trash directory to their respective original place(s) or to inactive pane if no place is known or if <Ctrl> is pressed when action is initiated
key.fake				Y	issue fake keypress event(s) according to action-arguments. Each argument must be in a form parsable by gtk e.g. <Ctrl><Alt>m,  sequential args separated by a space char (for an actual space key, 'space' without the quotes)
task.abort				N	select from a menu a running command or action and then brute-force terminate it (for emergencies, it leaks a lot)
Enquire on the emelFM2 mail-list for more information about the above.

ACTIONS FOR PLUGINS
command.detfind			N	run extended find-item dialog
command.renext			N	run extended rename dialog
command.track			N	run tracker-GUI dialog
configure.manage		N	import/export config data
file.acl				N	set or change access control list(s) of selected items
file.copy_acl			N	recursively copy ACL(s) only of selected items respectively to matching items in the inactive pane
file.clone				N	copy selected items to active pane, after rename
file.cpbar				N	copy selected items with a progress bar and stop/pause potential
file.cpbar_with_time	N	copy selected items with original atime, mtime and with a progress bar and stop/pause potential
file.du					O	determine disk usage of active-pane selected items (if no argument) or items whose name matches supplied argument (name or matchable pattern)
file.foreach			N	run an entered command on each selecte item
file.mvbar				N	move selected items with a progress bar and stop/pause potential
file.copy_name			N	copy names, or (with <Shift>) paths, of selected items to clipboard (with <Control> with a newline between each)
file.pack				N	create an archive including the selected items
file.retag				N	re-select any previously-logged item(s) now in active pane
file.tag				N	log selected item(s) in active pane
file.timeset			N	change atime, mtime or (if root user) ctime of selected items
file.shred				N	overwrite/obfuscate, then delete, selected item(s) from active pane
file.unpack				N	unpack an archive into a temporary directory
file.view_with_plugin	N	open first selected item with internal viewer (same as internal action)
fllelist.glob			O	select (with <Control> extra) items using rules similar to filepane filters Arg may be 1 or 2 or missing
filelist.sort_by_ext	O	sort filelist by filename extension Arg may be 1 or 2 or missing
filelist.selmatch       O   select items already selected in the other pane Arg may be 1 or 2 or missing
filelist.thumbs			O	open thumbnails dialog for a pane Arg may be 1 or 2 or missing
panes.compare			N	select items in active pane which are matched in inactive pane

UI-RELATED "PSEUDO ACTIONS" which don't actually do anything
bookmark.<menu>			Y	taskbar bookmark items Parameter = TBA
command.<line>			Y	combobox for specifying commands to be executed Parameter = min,max or ,max or min,expand. Min and max are size limits (in pixels). If no min is provided, 100 is used. 'expand' in effect is no maximum
file.<actions>			N	list of filetype-specific actions and/or commands, used in a filepane context menu
file.<handlers>			N	list of applications which can open the focused item, used in a filepane context menu
mountpoints.<menu>		Y	menu of mountable and unmountable devices. Parameter = name of toolbar where the button resides, same as the corresponding page name in the config dialog
pane1.<bookmarks>		Y	the bookmarks list, if it is shown in pane1 toolbar Parameter = TBA
pane1.<filter>			N	filters menu for items shown in pane 1
pane1.<line>			N	combobox for specifying the dir shown in pane 1. See command.<lne> for parameters description
pane2.<bookmarks>		Y	the bookmarks list, if it is shown in pane2 toolbar Parameter = TBA
pane2.<filter>			N	filters menu for items shown in pane 2
pane2.<line>			N	combobox for specifying the dir shown in pane 2. See command.<lne> for parameters description
plugin.<menu>			N	menu of plugins as may be displayed in a context menu
<separator>			N	separator in a toolbar or context menu
<submenu>			N	submenu in a toolbar or context menu
