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GRB 201015A is a long-duration Gamma-Ray Burst (GRB) which was detected atvery high energies (> 100 GeV) using the MAGIC telescopes. If confirmed, thiswould be the fifth and least luminous GRB ever detected at this energies. Weperformed a radio follow-up of GRB 201015A over twelve different epochs, from1.4 to 117 days post-burst, with the Karl G. Jansky Very Large Array, e-MERLINand the European VLBI Network. We included optical and X-rays observations,performed with the Multiple Mirror Telescope and the Chandra X-ray Observatoryrespectively, together with publicly available data. We detected a point-liketransient, consistent with the position of GRB 201015A until 23 and 47 dayspost-burst at 1.5 and 5 GHz, respectively. The source was detected also in bothoptical (1.4 and 2.2 days post-burst) and X-ray (8.4 and 13.6 days post-burst)observations. The multi-wavelength afterglow light curves can be explained withthe standard model for a GRB seen on-axis, which expands and decelerates into amedium with a homogeneous density, while a circumburst medium with a wind-likeprofile is disfavoured. Notwithstanding the high resolution provided by theVLBI, we could not pinpoint any expansion or centroid displacement of theoutflow. If the GRB is seen at the viewing angle which maximises the apparentvelocity, we estimate that the Lorentz factor for the possible proper motion is$\Gamma_{\alpha}$ < 40 in right ascension and $\Gamma_{\delta}$ < 61 indeclination. On the other hand, if the GRB is seen on-axis, the size of theafterglow is <5 pc and <16 pc at 25 and 47 days. Finally, the early peak in theoptical light curve suggests the presence of a reverse shock component before0.01 days from the burst.

VLBI observations of GRB 201015A, a relatively faint GRB with a hint of Very High Energy gamma-ray emission