Radio and high-energy variable emission from a multi-wavelength follow-up study of the infant planet-hosting star V1298,Tau

V1298,Tau is a very young and magnetically active K1V star that hosts a benchmark multi-planetary system in which planet formation and evolutionary history can be studied at the earliest stages. Because of the high interest in this system, it has been the target of a number of multi-wavelength follow-up so far. Between 2025 and 2026, we conducted a campaign to monitor the variability of V1298,Tau in radio (band C), X-ray, and near-UV (NUV) bands with the support of publicly available contemporary optical light curve. We also investigated multi-band correlations to link the emission to stellar activity. Radio observations were carried out with the Karl G. Jansky Very Large Array (JVLA) in band C (4.5--6.5 GHz) between the end of October 2025 and early February 2026. X-ray and NUV observations were carried out with the Swift satellite over 20 days, ending one month before the radio campaign began. We analysed the temporal variability of peak (integrated) fluxes in the C band and of X-ray (NUV) luminosities on various timescales by comparing it with the variability observed in the high-cadence optical light curve collected by the ASAS-SN survey. We observed both radio and high-energy time-variable emission. In the radio, JVLA detected emission in 90% of the visits, switching between high- (≥0.1 mJy/beam) and low-flux states in a matter of days or hours. The fluxes are moderately correlated with the optical light curve, suggesting modulation with the stellar rotation period. Except for one visit, the dynamic spectral analysis did not reveal short-term (minutes) variability, nor is there any evidence of circularly polarised emissions. Overall, the radio observations can be explained as gyrosynchrotron and/or cyclotron emission from the corona that is linked to stellar magnetic activity. At high energy, we detected significant variability in the X-ray luminosity (within the range ∼1.2--2.5times10 +30 erg/s), the decay phase of a stellar flare, and evidence of a correlation with the optical flux. Our data confirm that V1298,Tau follows the near-linear Güdel-Benz relation, with radio and X-ray luminosities consistent with those measured for magnetically active pre-main-sequence stars.