The Generate GTFS Shapes toolbox produces a new shapes.txt file for your GTFS dataset or allows you to edit an existing one.
The optional GTFS shapes.txt file contains the actual on-street paths taken by transit vehicles in your system. A good shapes.txt file is important in order for GTFS-based routing apps to display transit routes correctly on the map. This blog post explains more about why you should have a shapes.txt file and how you can use this tool to create one. Also check out the technical details of the shapes.txt file in the GTFS reference page.
Generate GTFS Shapes is targeted primarily toward transit agencies seeking to improve their GTFS datasets.
To create an entirely new shapes.txt file from scratch, you give the tool a valid, existing GTFS dataset, and the tool creates a new shape.txt file and updates the shape_id field in trips.txt and the shape_dist_traveled field in stop_times.txt. Step 1 of the tool creates a feature class with good estimates for the on-street paths used in your transit system. You can edit this feature class using your own knowledge in order to ensure that the correct paths are truly represented. Then, you can use Step 2 to of the tool to export your new shapes to a valid shapes.txt file and updated trips.txt and stop_times.txt files.
To edit one or more existing shapes, you give the tool a valid, existing GTFS with a shapes.txt file and choose the shape(s) you want to edit. The chosen shape(s) will be drawn in the map, where you can edit them. Then, you can use Step 2 to of the tool to export and updated shapes.txt file and stop_times.txt.
The tools will not overwrite any existing GTFS files. You can choose the output location for the new files, and you can compare them with the old ones before manually replacing the old ones with the updated ones.