  The James Webb Space Telescope (JWST) will revolutionize the field of
high-contrast imaging and enable both the direct detection of Saturn-mass
planets and the characterization of substellar companions in the mid-infrared.
While JWST will feature unprecedented sensitivity, angular resolution will be
the key factor when competing with ground-based telescopes. Here, we aim to
characterize the performance of several extreme angular resolution imaging
techniques available with JWST in the 3-5 micron regime based on data taken
during commissioning. Firstly, we introduce custom tools to simulate, reduce,
and analyze NIRCam and MIRI coronagraphy data and use these tools to extract
companion detection limits from on-sky NIRCam round and bar mask coronagraphy
observations. Secondly, we present on-sky NIRISS aperture masking
interferometry (AMI) and kernel phase imaging (KPI) observations from which we
extract companion detection limits using the publicly available fouriever tool.
Scaled to a total integration time of one hour and a target of the brightness
of AB Dor, we find that NIRISS AMI and KPI reach contrasts of $\sim$7-8 mag at
$\sim$70 mas and $\sim$9 mag at $\sim$200 mas. Beyond $\sim$250 mas, NIRCam
coronagraphy reaches deeper contrasts of $\sim$13 mag at $\sim$500 mas and
$\sim$15 mag at $\sim$2 arcsec. While the bar mask performs $\sim$1 mag better
than the round mask at small angular separations $\lesssim$0.75 arcsec, it is
the other way around at large angular separations $\gtrsim$1.5 arcsec.
Moreover, the round mask gives access to the full 360 deg field-of-view which
is beneficial for the search of new companions. We conclude that already during
the instrument commissioning, JWST high-contrast imaging in the L- and M-bands
performs close to its predicted limits.
