Both are supposed to work

There isn't an explicit API for this, although it's been asked before. But you can do it programmatically with (babashka.deps/add-deps (edn/parse-string (slurp "deps.edn")) {:aliases [:foo]})

You can do this by placing those coercions on the namespace metadata and then exec functions from that namespace

The :task code doesn't have a namespace. So I think you're saying I would need an external bb script that the task would call to parse the arguments?

Can you tell me how you would use those coercions in tasks? Maybe it's best to talk from there

I'm back working on test running, and planning to try using cognitect/cljs test runner across the board. I need a separate task for each test environment, where each needs the arguments parsed to pass into cognitect.test-runner.api/test.

:task (exec 'cognitect.test-runner.api/test)
:org.babashka/cli {:coerce {:dirs []
                            :nses [:symbol]
                            :patterns []
                            :vars [:symbol]
                            :includes [:keyword]
                            :excludes [:keyword]
                            :only [:symbols]}}

Actually... maybe I don't need that at all except for BB test. I guess for other enviroments I would be using (clojure ...). Can I just pass the arguments unchanged to that?

I've made a little wrapper like this, which is used for running clojure tests for babashka CLI itself: https://github.com/babashka/cli/blob/main/test/babashka/test_runner.clj

the deps.edn config: https://github.com/babashka/cli/blob/30f9201dafe60f157b6c9de2ec6d68b2f3ef2cac/deps.edn#L6-L13

and then you can do:

clojure -M:test --vars foo.bar/baz 

or you can do:

clojure -X:test :vars '[foo.bar/baz]' 

and when called from tasks, this becomes: (clojure "-X:test" :vars '[foo.bar/baz]) since arguments are stringified

thx. I'll take a look