This is a question I get a lot from parents during parent/teacher conferences and yes, it is okay. If after age 7 they consistently still do this, then it is time to dig deeper into why this is happening.
I challenge you to try this! Too often we use the words, “good job” but what do those words mean to a child? Those words can be so vague and overused that it is hard for kids to understand exactly what the “good job” is.
By describing what you liked about what they did you are giving them a clear picture of what you liked, what is appropriate behavior and reinforcing the fact that you are really interested in what they just accomplished.