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
KoalaWriter
Deep, per-section research is built into the writer.
The official Deep Research page says it fetches live SERPs per section, scrapes up to 5 URLs per section, and feeds source content into the prompt: https://koala.sh/features/deep-research