I am trying to programatically find out whether a given company has a google knowledge panel. for instance, when i search google for the company "Aeronaut Brewing Company", I get a sidebar that displays relevant information about the company. This is called the knowledge panel. Google's knowledge graph api is supposed to return this information, and for aeronaut it does:
However, I've noticed that plenty of companies who have a knowledge panel do not show up in google knowledge graph api. for instance:
The Affton Chamber of Commerce has a sidebar on google (link), but a google knowledge graph search comes back as only the following JSON (basically it's empty):
@context
@vocab "http://schema.org/"
goog "http://schema.googleapis.com/"
EntitySearchResult "goog:EntitySearchResult"
detailedDescription "goog:detailedDescription"
kg "http://g.co/kg"
@type "ItemList"
itemListElement []
What's going on? Shouldn't google knowledge graph API contain everything that has a knowledge panel on google??