Forward-fitting synthetic STIX visibilities associated with configurations mimicking three non-thermal emissions, by means of AMOEBA and PSO. First row: simulated configurations (the values of the configuration parameters are given in Table 4). Second and third rows: examples of the kind of reconstruction most frequently provided by VIS_FWDFIT. Fourth and fifth rows: examples of the kind of reconstruction most frequently provided by VIS_FWDFIT_PSO.