We are achieving this using Service Operations Workspace and the Agent Assist pane. The pane surfaces KB articles that are likely relevant to the Incident (based on the Short Description). There is an Attach option in the article. By default, it places the Permalink URL in the Customer Visible notes and then immediately saves the Incident (which may lead to an email being sent to the Contacting Client). We modified the OOB action to put the URL in the Work Notes instead and the knowledge worker can decide if they want to send the URL to the customer or not.
The same workflow is available in Agent Workspace and the Agent Assist pane there.
In Classic UI, if the Related Search Results option is enabled, a search area is added to the Incident form, and KB articles are surfaced, and attaching is also possible.
I don't know what KM system you are following but I caution you on setting goals on attach rate. Knowledge workers will attach something just because they have to but it might not be relevant to the resolution of the INC. This then skews the data around which articles are being attached the most and the opportunity to use that data for process improvement.
We follow the KCS methodology which stresses setting goals on outcomes, not activities. If it's easy to manipulate, then don't measure it. We are looking more at the relevancy of what has been attached versus a 100% attachment rate.
