How to override the error msg for this error?

[durianwaffle]

Hi Langium community, in our grammar only some special characters allowed after escape character $.
When user typed something wrong such as '$wq' in this case, there will be default error msgs.
May I know how can I override those error msgs?

[msujew]

Hey @durianwaffle, that's a lexer error and I've already answered this question as part of #1715 (comment).

[durianwaffle]

Okay thank you @msujew !

[durianwaffle]

Why it's parser error not lexer error nor token error?

[msujew]

It's a lexer error.

[durianwaffle]

Okay, thank you @msujew !