Assert what the page's generator meta tag says: the whole content ("be"), its start ("start with") or a part of it ("contain"), without regard to case. The name of the generator is a value of the step: every page the platform hosts carries <meta name="generator" content="HubSpot">.
Examples
Then the page generator should be "HubSpot"
And the page generator should contain "HubSpot"
Then the page generator should start with "Hub"
But the page generator should not be "WordPress"
Then page generator should be "HubSpot"
Pattern
Then(/^(?:the )?page generator should( not)* (be|start with|contain) "([^"]*)"$/, …)
Part of @webship-js/hubspot-cms-steps (github.com/webship/hubspot-cms-steps), a step pack for Webship-js 2.0.x.