F200W − F356W color vs. F356W magnitude distribution of JWST-detected sources in the J1030 field. The gray dots represent the extended sources, while point-like sources are shown as yellow filled circles. Stars align along a horizontal sequence at F200W − F356W ∼ −0.9. Faint (F356W >  24) and red (F200W − F356W >  0) point-like objects (filled circles with red contour) are mostly LRD candidates at z >  4 (e.g., ID4879 at z = 5.95; see text for details). The three bright (F356W <  23), point-like objects above the stellar sequence are two standard, X-ray detected broad line AGNs (J1030 and XID10, shown as filled circles with blue contours) and the BiRD (purple pentagon; see text for details). The dotted line shows the track followed by the BiRD if moved at different redshifts as labeled from z = 2 to z = 7. The smaller pentagons show for comparison the position of two spectroscopically confirmed LRDs at cosmic noon, discovered with JWST, namely the Rosetta Stone at z = 2.26 (plum; Juodžbalis et al. 2024a) and RUBIES-BLAGN-1 at z = 3.1 (pink; Wang et al. 2025). The colored box shows the selection region used to compute the space density of LRDs at cosmic noon (see Section 5.4).