Anatomy of a pyRevit Script

pyRevit provides a few basic services to python scripts that use its engine. These fuctionalities are accessible through a few high level modules. This article is a quick look at these services and their associated python modules.

Script Metadata Variables

pyRevit looks for certain global scope variables in each scripts that provide metadata about the script and follow the __<name>__ format.


Button Title: When using the bundle name as the button name in Revit UI is not desired, or you want to add a newline character to the command name to better display the butonn name inside Revit UI Panel, you can define the __title__ variable in your script and set it to the desired button title.

__title__ = 'Sample\\nCommand'


Button Tooltip: Tooltips are displayed similar to the other buttons in Revit interface. You can define the tooltip for a script using the doscstring at the top of the script or by explicitly defining __doc__ metadata variable.

# defining tooltip as the script docstring
"""You can place the docstring (tooltip) at the top of the script file.
This serves both as python docstring and also button tooltip in pyRevit.
You should use triple quotes for standard python docstrings."""
# defining tooltip by setting metadata variable
__doc__ = 'This is the text for the button tooltip associated with this script.'


Script Author: You can define the script author as shown below. This will show up on the button tooltip.

__author__ = 'Ehsan Iran-Nejad'


F1 Shortcut Help Url: xx


Min Revit Version Required: xx


Max Revit Version Supported: xx


Script In Beta: xx


Command Availability: Revit commands use standard IExternalCommandAvailability class to let Revit know if they are available in different contexts. For example, if a command needs to work on a set of elements, it can tell Revit to deactivate the button unless the user has selected one or more elements.

In pyRevit, command availability is set through the __context__ variable. Currently, pyRevit support three types of command availability types.

# Tool activates when at least one element is selected
__context__ = 'Selection'

# Tools are active even when there are no documents available/open in Revit
__context__ = 'zerodoc'

# Tool activates when all selected elements are of the given category or categories
__context__ = '<Element Category>'
__context__ = ['<Element Category>', '<Element Category>']

If category name starts with ‘OST_’ (e.g. ‘OST_Doors’) comparison will be made using BuiltInCategory. It allows to use your script in spite of Revit translation

List of available categories

<Element Category> can be any of the standard Revit element categories. See Appendix B: System Category Names for a full list of system categories. You can use the List tool under pyRevit > Spy and list the standard categories.

Here are a few examples:

# Tool activates when all selected elements are of the given category

__context__ = 'Doors'
__context__ = 'Walls'
__context__ = 'Floors'
__context__ = 'OST_Doors'
__context__ = ['Space Tags', 'Spaces']

pyrevit.script Module

All pyRevit scripts should use the pyrevit.script module to access pyRevit functionality unless listed otherwise. pyRevit internals are subject to changes and accessing them directly is not suggested.

Here is a list of supported modules for pyRevit scripts. Examples of using the functionality in these modules are provided on this page.


This module provides access to output window (pyrevit.output), logging (pyrevit.coreutils.logger), temporary files (pyrevit.coreutils.appdata), and other misc features. See the module page for usage examples and full documentation of all available functions.


You can get the default logger for the script using pyrevit.script.get_logger().

from pyrevt import script

logger = script.get_logger()'Test Log Level :ok_hand_sign:')

logger.warning('Test Log Level')

logger.critical('Test Log Level')

Critical and warning messages are printed in color for clarity. Normally debug messages are not printed. you can hold CTRL and click on a command button to put that command in DEBUG mode and see all its debug messages

logger.debug('Yesss! Here is the debug message')

Controlling Output Window

Each script can control its own output window:

from pyrevit import script

output = script.get_output()

output.set_title('More control please!')

See Effective Output/Input for more info.

Script Config

Each script can save and load configuration pyRevit’s user configuration file:

See pyrevit.output for more examples.

See pyrevit.script.get_config() and pyrevit.script.save_config() for the individual functions used here.

from pyrevit import script

config = script.get_config()

# set a new config parameter: firstparam
config.firstparam = True

# saving configurations

# read the config parameter value
if config.firstparam:

Logging Results

pyRevit has a usage logging system that can record all tool usages to either a json file or to a web server. Scripts can return custom data to this logging system.

In example below, the script reports the amount of time it saved to the logging system:

from pyrevit import script

results = script.get_results()
results.timesaved = 10

Using Temporary Files

Scripts can create 3 different types of data files:

  • Universal files

    These files are not marked by host Revit version and could be shared between all Revit versions and instances. These data files are saved in pyRevit’s appdata directory and are NOT cleaned up at Revit restarts.

    See pyrevit.script.get_universal_data_file()


    Script should take care of cleaning up these data files.

    # provide a unique file id and file extension
    # Method will return full path of the data file
    from pyrevit import script
    script.get_universal_data_file(file_id, file_ext)
  • Data files

    These files are marked by host Revit version and could be shared between instances of host Revit version Data files are saved in pyRevit’s appdata directory and are NOT cleaned up when Revit restarts.

    See pyrevit.script.get_data_file()


    Script should take care of cleaning up these data files.

    # provide a unique file id and file extension
    # Method will return full path of the data file
    from pyrevit import script
    script.get_data_file(file_id, file_ext)
  • Instance Data files

    These files are marked by host Revit version and process Id and are only available to current Revit instance. This avoids any conflicts between similar scripts running under two or more Revit instances. Data files are saved in pyRevit’s appdata directory (with extension .tmp) and ARE cleaned up when Revit restarts.

    See pyrevit.script.get_instance_data_file()

    # provide a unique file id and file extension
    # Method will return full path of the data file
    from pyrevit import script
  • Document Data files

    (Shared only between instances of host Revit version): These files are marked by host Revit version and name of Active Project and could be shared between instances of host Revit version. Data files are saved in pyRevit’s appdata directory and are NOT cleaned up when Revit restarts.

    See pyrevit.script.get_document_data_file()


    Script should take care of cleaning up these data files.

    # provide a unique file id and file extension
    # Method will return full path of the data file
    from pyrevit import script
    script.get_document_data_file(file_id, file_ext)
    # You can also pass a document object to get a data file for that
    # document (use document name in file naming)
    script.get_document_data_file(file_id, file_ext, doc)

Appendix A: Builtin Parameters Provided by pyRevit Engine

Variables listed below are provided for every script in pyRevit.


It’s strongly advised not to read or write values from these variables unless necessary. The pyrevit module provides wrappers around these variables that are safe to use.

# Revit UIApplication is accessible through:

# Command data provided to this command by Revit is accessible through:

# selection of elements provided to this command by Revit

# pyRevit engine manager that is managing this engine

# This variable is True if command is being run in a cached engine

# pyRevit external command object wrapping the command being run

# information about the pyrevit command being run
__commandpath__             # main script path
__alternatecommandpath__    # alternate script path
__commandname__             # command name
__commandbundle__           # command bundle name
__commandextension__        # command extension name
__commanduniqueid__         # command unique id

# This variable is True if user CTRL-Clicks the button

# This variable is True if user SHIFT-Clicks the button

# results dictionary

Appendix B: System Category Names

Adaptive Points
Air Terminal Tags
Air Terminals
Analysis Display Style
Analysis Results
Analytical Beam Tags
Analytical Beams
Analytical Brace Tags
Analytical Braces
Analytical Column Tags
Analytical Columns
Analytical Floor Tags
Analytical Floors
Analytical Foundation Slabs
Analytical Isolated Foundation Tags
Analytical Isolated Foundations
Analytical Link Tags
Analytical Links
Analytical Node Tags
Analytical Nodes
Analytical Slab Foundation Tags
Analytical Spaces
Analytical Surfaces
Analytical Wall Foundation Tags
Analytical Wall Foundations
Analytical Wall Tags
Analytical Walls
Annotation Crop Boundary
Area Load Tags
Area Tags
Assembly Tags
Boundary Conditions
Brace in Plan View Symbols
Cable Tray Fitting Tags
Cable Tray Fittings
Cable Tray Runs
Cable Tray Tags
Cable Trays
Callout Boundary
Callout Heads
Casework Tags
Ceiling Tags
Color Fill Legends
Communication Device Tags
Communication Devices
Conduit Fitting Tags
Conduit Fittings
Conduit Runs
Conduit Tags
Connection Symbols
Contour Labels
Crop Boundaries
Curtain Grids
Curtain Panel Tags
Curtain Panels
Curtain System Tags
Curtain Systems
Curtain Wall Mullions
Data Device Tags
Data Devices
Detail Item Tags
Detail Items
Displacement Path
Door Tags
Duct Accessories
Duct Accessory Tags
Duct Color Fill
Duct Color Fill Legends
Duct Fitting Tags
Duct Fittings
Duct Insulation Tags
Duct Insulations
Duct Lining Tags
Duct Linings
Duct Placeholders
Duct Systems
Duct Tags
Electrical Circuits
Electrical Equipment
Electrical Equipment Tags
Electrical Fixture Tags
Electrical Fixtures
Electrical Spare/Space Circuits
Elevation Marks
Filled region
Fire Alarm Device Tags
Fire Alarm Devices
Flex Duct Tags
Flex Ducts
Flex Pipe Tags
Flex Pipes
Floor Tags
Foundation Span Direction Symbol
Furniture System Tags
Furniture Systems
Furniture Tags
Generic Annotations
Generic Model Tags
Generic Models
Grid Heads
Guide Grid
HVAC Zones
Imports in Families
Internal Area Load Tags
Internal Line Load Tags
Internal Point Load Tags
Keynote Tags
Level Heads
Lighting Device Tags
Lighting Devices
Lighting Fixture Tags
Lighting Fixtures
Line Load Tags
Masking Region
Mass Floor Tags
Mass Tags
Material Tags
Mechanical Equipment
Mechanical Equipment Tags
MEP Fabrication Containment
MEP Fabrication Containment Tags
MEP Fabrication Ductwork
MEP Fabrication Ductwork Tags
MEP Fabrication Hanger Tags
MEP Fabrication Hangers
MEP Fabrication Pipework
MEP Fabrication Pipework Tags
Multi-Category Tags
Multi-Rebar Annotations
Nurse Call Device Tags
Nurse Call Devices
Panel Schedule Graphics
Parking Tags
Part Tags
Pipe Accessories
Pipe Accessory Tags
Pipe Color Fill
Pipe Color Fill Legends
Pipe Fitting Tags
Pipe Fittings
Pipe Insulation Tags
Pipe Insulations
Pipe Placeholders
Pipe Segments
Pipe Tags
Piping Systems
Plan Region
Planting Tags
Plumbing Fixture Tags
Plumbing Fixtures
Point Clouds
Point Load Tags
Project Information
Property Line Segment Tags
Property Tags
Railing Tags
Raster Images
Rebar Cover References
Rebar Set Toggle
Rebar Shape
Reference Lines
Reference Planes
Reference Points
Render Regions
Revision Cloud Tags
Revision Clouds
Roof Tags
Room Tags
Routing Preferences
Schedule Graphics
Scope Boxes
Section Boxes
Section Line
Section Marks
Security Device Tags
Security Devices
Shaft Openings
Site Tags
Space Tags
Span Direction Symbol
Specialty Equipment
Specialty Equipment Tags
Spot Coordinates
Spot Elevation Symbols
Spot Elevations
Spot Slopes
Sprinkler Tags
Stair Landing Tags
Stair Paths
Stair Run Tags
Stair Support Tags
Stair Tags
Stair Tread/Riser Numbers
Structural Annotations
Structural Area Reinforcement
Structural Area Reinforcement Symbols
Structural Area Reinforcement Tags
Structural Beam System Tags
Structural Beam Systems
Structural Column Tags
Structural Columns
Structural Connection Tags
Structural Connections
Structural Fabric Areas
Structural Fabric Reinforcement
Structural Fabric Reinforcement Symbols
Structural Fabric Reinforcement Tags
Structural Foundation Tags
Structural Foundations
Structural Framing
Structural Framing Tags
Structural Internal Loads
Structural Load Cases
Structural Loads
Structural Path Reinforcement
Structural Path Reinforcement Symbols
Structural Path Reinforcement Tags
Structural Rebar
Structural Rebar Coupler Tags
Structural Rebar Couplers
Structural Rebar Tags
Structural Stiffener Tags
Structural Stiffeners
Structural Truss Tags
Structural Trusses
Switch System
Telephone Device Tags
Telephone Devices
Text Notes
Title Blocks
View Reference
View Titles
Wall Tags
Window Tags
Wire Tags
Zone Tags