GET /api/v2/lists or MCP lists_catalog(). Select rows with ingested: true. Each row gives its source_key, category, current entry count, publisher, source URL and available crawl/coverage dates. Declared sources without ingestion are not evidence of screening coverage. The Arena’s source choices read this live catalog; if discovery fails, its compiled fallback is explicitly labelled.
lists_catalog, list_entries_search, screening_match or exposure_search tools with their advertised parameters. Use get_parameter_options for unfamiliar accepted choices. Source discovery remains live, so the compiled enum snapshot can contain fewer keys than the current catalog. Unloaded or unknown source keys return an availability error rather than a misleading empty screening result.
