PREVIS is a Python module that provides functions to help determine the observability of astronomical sources from long-baseline interferometers worldwide: VLTI (ESO, Chile) and CHARA (USA). PREVIS uses data from the Virtual Observatory (OV), such as magnitudes, Spectral Energy Distribution (SED), celestial coordinates or Gaia distances. Then, it compares the target brightness to the limiting magnitudes of each instrument to determine whether the target is observable with present performances. PREVIS includes main facilities at the VLTI with PIONIER (H band), GRAVITY (K band) and MATISSE (L, M, N bands), and at CHARA array with VEGA (V band), PAVO (R bands), MIRC (H band), CLIMB (K band) and CLASSIC (H, K bands). PREVIS also uses the V or G magnitudes to check the guiding restriction or the tip/tilt correction limit. For the VLTI: if the star is too faint in G mag, PREVIS will look for the list of stars around the target (57 arcsec) with the appropriate magnitude and give the list of celestial coordinates usable as the guiding star.

AMICAL (Aperture Masking Interferometry Calibration and Analysis Library) processes Aperture Masking Interferometry (AMI) data from major existing facilities, such as NIRISS on the JWST, SPHERE and VISIR from the European Very Large Telescope (VLT) and VAMPIRES from SUBARU telescope. The library cleans the reduced datacube from the standard instrument pipelines, extracts the interferometrical quantities (visibilities and closure phases) using a Fourier sampling approach, and calibrates those quantities to remove the instrumental biases. In addition, two external packages (CANDID and Pymask) are included to analyze the final outputs obtained from a binary-like sources (star-star or star-planet); these stand-alone packages are interfaced with AMICAL to quickly estimate scientific results (e.g., separation, position angle, contrast ratio, and contrast limits) using different approaches.