$onlyIfMessageContains is a convenience guard that checks whether the user’s entire message contains a specific substring. It is simpler and more focused than $onlyIf — you don’t need to write a condition expression; just provide the text you’re looking for.

How It Works

1. The function checks if text appears anywhere within $message (the full user message).
2. If the text is found → execution continues.
3. If the text is not found → execution stops silently (no message is sent).

The matching is case-sensitive and works like a simple substring search. For example, $onlyIfMessageContains[hello] will match hello world but not Hello World or hell.

When to Use

• Quick keyword gates: require that the message mentions a specific word before processing.
• Format validation: ensure the message contains expected delimiters or markers (like @ for mentions, # for channels, etc.).
• Category filtering: route commands based on message content tags.

When Not to Use

• For complex conditions → use $onlyIf instead.
• For argument count checks → use $argsCheck.
• When you need to send an error message on failure → use $onlyIf[$messageContains[$message;text]==true;error] instead.

Comparison with Manual Check

Without $onlyIfMessageContains:

$if[$messageContains[$message;!admin]==false]
$stop
$endif

With $onlyIfMessageContains (equivalent, cleaner):

$onlyIfMessageContains[!admin]