RIGShare API key (Bearer format). Required only for the authenticated tools: rigshare_list_my_bookings, rigshare_list_my_sessions, rigshare_create_booking, and rigshare_create_listing (equipment:write scope). Without it, the public read-only tools (search, details, categories, owner onboarding) still work. Get a key at https://www.rigshare.app/profile#api-keys or contact support@rigshare.app.
