Error message not specific enough for wrong help of/COMMAND commands

[nus-pe-bot]

Steps to Reproduce:

1. Open App
2. Enter "help of/DDD" or any invalid command in the place of DDD

Expected Behavior: Should display that this is a help command that is written wrongly, and also additionally display how such "help of" commands should be properly entered.

Actual Behavior: Displays "This is not a valid command," which is not specific enough.

---

_{[original: nus-cs2103-AY2021S1/pe-interim#6028]}

[zhxchd]

Team's Response

The severity is veryLow because the error message "This is not a valid command" can be interpreted as "The command argument (in your case it's "d") is not a valid command", which makes sense.
We accepted this issue because it is still a bit ambiguous and it is better to include the invalid command input in the error message as well.

Duplicate status (if any):

--