You only delete all room or a specific history: https://confluence.atlassian.com/display/HIPCHAT/Delete+messages+and+files
But I found a chrome plugin to clear all history https://chrome.google.com/webstore/detail/hipchat-history-cleaner/cljfdgmalikglkefpoacplgeefpaebgk?hl=en. I think you are looking for something like that.
Earlier this year we made the difficult decision to discontinue our team messaging tools, Stride and Hipchat. The end of life date for Stride and Hipchat Cloud is quickly approaching - February 15, 2...
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