A separate hosted product. Not a plugin, and not required to run WP-Lister.
In detail
What each one is, without the brochure voice.
Established, since 2012
WP-Lister for eBay and Amazon
Two WordPress plugins that publish your WooCommerce catalogue to a marketplace and keep it in step. Stock changes in WooCommerce reach the marketplace, and orders placed there come back into your shop. Listing profiles handle the per-channel rules. Hooks let a developer change any of it.
The layer underneath the plugins. It manages AI tokens and credits once instead of once per channel, and it carries the tools you want when something goes wrong: a debugger for sync behaviour, a database health check, a repair pass and a rollback.
A hosted analytics product that reads across the marketplaces you sell on. We're saying this twice because it gets confused: MerchantPulse is not a WP-Lister plugin, it doesn't install into WordPress, and you don't need it to list anything.
If you bought WP-Lister years ago, nothing here replaces it. TriLister sits alongside the plugins you already run, and the customer portal is still where licences, downloads and renewals live.