Finding the ID of a system-custom field

My app will be installed in several jira instances
I need to work with some system - custom fields: that is, fields reserved for the system that are defined as custom: for example - story points or advanced roadmap’s Team field. In every instance of Jira cloud these fields may have a different ID.
I’m looking for a way to locate these fields’ IDs. Searching by name might not be good enough as there may be another field with the same name. Any ideas?


A good way to identify some fields is by field.schema.custom, i.e. roadmaps team field should have ‘com.atlassian.teams:rm-teams-custom-field-team’.
There are some fields where you may not be able to use this method, as the field is just a standard float field. StoryPoints is unfortunately of of these fields.
In case no one knows a better way, you may use the untranslated name and in case you are not able to identify the field:
Add a configuration where the user is able to set the field manually

Thank you for your reply, it’s very helpful.

The REST call /rest/api/3/field also shows the ids for system fields