Minor Description
Instead of failing, v2 API introspect requests that filter for a non-existent command succeed and show null for the command spec.
E.g., after bin/solr start -e cloud -noprompt, curl "http://localhost:8983/v2/c/gettingstarted/_introspect?method=POST&command=XXXXX&indent=on" returns:
{
"spec":[{
"documentation":"https://cwiki.apache.org/confluence/display/solr/Collections+API",
"description":"Several collection-level operations are supported with this endpoint: modify collection attributes; reload a collection; migrate documents to a different collection; rebalance collection leaders; balance properties across shards; and add or delete a replica property.",
"methods":["POST"],
"url":{"paths":["/collections/{collection}",
"/c/{collection}"]},
"commands":{"XXXXX":null}}],
"WARNING":"This response format is experimental. It is likely to change in the future.",
"availableSubPaths":{ [...] }
}