Research depth
Discovery
How well the tool supports keyword, competitor, SERP, backlink, or market research before execution.
AthenaHQ
Strong AI-search research surface spanning prompts, responses, sources, competitors, citation intelligence, and prompt-volume estimates.
The plans comparison lists prompt volume estimation/analysis, prompt variations and conversation context, unlimited competitor tracking/benchmarking, and citation intelligence. https://athenahq.ai/pricing
Scalenut
Deep SERP, competitor, topic, prompt, and page-level research is documented, though the site does not document every possible data source.
The Features FAQ says SERP statistics come from the top 30 ranking articles and Cruise Mode breaks down the top 10/20/30 competitor outlines: https://www.scalenut.com/features