Finding values associated with a dropdown can be done with the workspace schema.
In order to access the workspace schema, you will first need to locate your workspace object ID. Use the following article to identify your workspace object ID: https://knowledge.broadcom.com/external/article/47763/rally-find-object-ids-of-current-worksp.html
If you are working in a browser, it is recommended to install a JSON formatter browser extension since the response will not be easily read without formatting.
After acquiring the workspace object ID, access the following URL:
From here, you can search for the field name. Bear in mind that you might see the field names mentioned multiple times. The reason the field may be mentioned multiple times is that they represent the different work items. For example, if you have a custom field with the same name that is configured for user stories and defects, you will see that mentioned twice in the schema. Because of this, you will need to validate that the field definition is the correct one you're looking for.
That information is contained in the TypeDefinition of the AttributeDefinition.
The path is:
Schema -> AttributeDefinition -> TypeDefinition -> TypePath
The TypePath indicates what work item or object type the custom field is defined against.
AllowedValues will be accessed in the following way:
Schema -> AttributeDefinition -> AllowedValues
keywords: agile central rally field dropdown