A keyword filter is a combination of a single keyword (e.g. library, tool, ...) and a list of strings, which should be contained in the package name. Custom keyword filters can be added.
The following example creates a filter that lists all packages with the keyword library which also contain simatic in the package name:
"siemens.apax-v3.registriesExplorer.ax.keywordFilters": [
{
"keyword": "library",
"search_terms": ["simatic"]
}
]