Activate Geoprocessing pane and open the tool dialog in the pane.
open_dialog
string input_points = @"C:\data\ca_ozone.gdb\ozone_points";
string output_polys = @"C:\data\ca_ozone.gdb\ozone_buff";
string buffer_dist = "2000 Meters";
var param_values = Geoprocessing.MakeValueArray(input_points, output_polys, buffer_dist);
Geoprocessing.OpenToolDialog("analysis.Buffer", param_values);
Open a script tool dialog in Geoprocessing pane
string input_data = @"C:\data\data.gdb\Population";
string out_pdf = @"C:\temp\Reports.pdf";
string field_name = "INCOME";
// use defaults for other parameters - no need to pass any value
var arguments = Geoprocessing.MakeValueArray(input_data, out_pdf, field_name);
string toolpath = @"C:\data\WorkflowTools.tbx\MakeHistogram";
Geoprocessing.OpenToolDialog(toolpath, arguments);
Target Platforms: Windows 11, Windows 10, Windows 8.1
ArcGIS Pro version: 2.0 or higher.