When I ran any terragrunt command, I got this error:
ERRO json: cannot unmarshal array into Go struct field Statement.Statement.Action of type string ERRO Unable to determine underlying exit code, so Terragrunt will exit with error code 1
Turns out this is what you get when you haven’t run
terraform init yet.
In general, if terragrunt is erroring, try terraform and see if you can get any more clues.