Perhaps the use of transformers during query can be documented more clearly with more examples?

[iai-rsa]

$2 = $1.transform(DropKeys, "keys=uid,gid") is an example from (https://github.com/ashish-gehani/SPADE/blob/master/src/spade/query/quickgrail/README.md) that works.
But when using other transformers, I get various errors.
For instance, $2 = $1.transform(Prune, "expression=name:sudo") gives the following error:
Invalid # of transformer arguments. Expected: [SOURCE_GRAPH, MAX_DEPTH, DIRECTION]
And, $2 = $1.transform(Blacklist) gives the following error:
Invalid # of transformer arguments. Expected: [SOURCE_GRAPH]

Thank you!

[iai-rsa]

By the way, adding these transformers in SPADE Control Client can be done successfully.
But during query, the following errors may appear:
Error: Failed to execute query: Prune'
Error: Failed to execute query: Blacklist'