I think you can do this via Webhooks. 

1. Catch hook
   • App: Webhooks by Zapier
   • Event: Catch Hook
   • Webhook URL: Support can help you set this up 
2. Filter
3. {Your slack actions}

You’re going to get the content in the payload for sure. Not sure about tags though (not seeing them in the example here)

Edited the original reply above to give you more specificication.

Also, I realized why tags don’t come through: Tags sit on the Topic, not on the reply. 

So if you want tags on from the reply, you could add a few steps (but they’ll eat up your Zap actions totals)

• PUT request to authenticate with the API
• GET request to get the additional info from original topic

Reading this again…

The New Reply Trigger probably takes care of your trigger, not webhooks. Then the filter option to stop the Zap unless it meets your conditions. 

It could also be paired well with another Zap where the initial New Topic trigger only goes through with specific tags. 

(sorry for the spam replies , I think I misread the original goal)

@tiffany.oda I think you could do this using Zapier and the inSided trigger today, then use a Zapier filter to determine whether or not to post in Slack.

Trigger: inSided

Filter: Filter by Zapier, choose the relevant field from inSided that you want to filter on (likely the ‘Content’, the condition, and the text

Action: Slack (if true based on the filter), send channel message or direct message

I think Danny and Scott are on the mark indeed. You’d run Zaps for all topics, but stop the Zap if the content of the post does not contain the keyword

You’d use the “contains” filter option: https://help.zapier.com/hc/en-us/articles/8496014252301