Synthetic transmission spectra of TOI-969 b. Fiducial models assuming a cloud-free atmosphere with solar abundances (bottom), cloud-free atmosphere with enhanced metallicity by a factor of 100 (middle), and atmosphere with solar abundances and an optically thick cloud deck with top pressure of 100 Pa (top). Estimated uncertainties are shown for the observation of one transit with JWST NIRISS-SOSS, NIRSpec-G395M, and MIRI-LRS configurations. Simulated data are color coded according to wavelength.