Correlate backend errors with real-user monitoring or session data to count the unique users an incident actually affected. Use this skill whenever the user mentions user impact, real user monitoring, rum, affected users, session correlation, blast radius users, revenue impact, or is working with Datadog RUM, Sentry, Grafana, even if they never say "user-impact quantification" explicitly. Routes live lookups through the Business-Impact-API endpoint. Do not use it for unrelated application feature work or general coding questions.
