Agent Skills: research-compare

Compare two or more alternatives in a structured tradeoff matrix — libraries, technologies, vendors, or approaches. Derives the comparison criteria from the decision context (or accepts caller-supplied criteria), researches each alternative on every criterion in parallel tracks across the hide-the-intent boundary, and builds an evidence-backed matrix where each cell carries a citation. Surfaces per-criterion tradeoffs factually (on X, A leads; on Y, B leads) but does NOT compute weighted scores or declare a winner — which weights matter, and which alternative wins, belongs to the orchestrator. Persists the matrix as a decision-input document. Mode-aware: interactive confirms criteria and reviews the matrix; autonomous returns the matrix path. The right capability for 'Postgres vs Cassandra for our workload', 'Stripe vs Adyen', 'REST vs GraphQL for this API'.