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Adds a custom informative message (severity of 0) to the messages of a script tool or Python toolbox tool.

When a tool is run, arcpy is fully aware of the application it is called from. One major effect of this is that you can write messages in Python and your messages automatically appear on the tool dialog box, in the history, and the Python window.


AddMessage (message)
ParameterExplanationData Type

The message to add.


Code sample

AddMessage example

Add a custom informative message to the Python script tool.

import arcpy

fc = arcpy.GetParameterAsText(0)

# Get the count from GetCount's Result object
feature_count = int(arcpy.GetCount_management(fc).getOutput(0))

if feature_count == 0:
    arcpy.AddError("{0} has no features.".format(fc))
    arcpy.AddMessage("{0} has {1} features.".format(fc, feature_count))

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