Reviewers mostly see HARPA AI as a highly useful browser extension that saves time and replaces several other tools at once. They repeatedly praise its versatility for writing, summarizing, keyword extraction, transcription, tab-aware prompts, and routine automations, with many saying it improves daily productivity and is easy to start using. A few note that the broad feature set and older interface could feel confusing at first, though the newer UI seems better received. The main sharp complaint is reliability and support, with one user reporting broken credit logic and no help.