  High-contrast imaging of debris disk systems permits us to assess the
composition and size distribution of circumstellar dust, to probe recent
dynamical histories, and to directly detect and characterize embedded
exoplanets. Observations of these systems in the infrared beyond 2--3 $\mu$m
promise access to both extremely favorable planet contrasts and numerous
scattered-light spectral features -- but have typically been inhibited by the
brightness of the sky at these wavelengths. We present coronagraphy of the AU
Microscopii (AU Mic) system using JWST's Near Infrared Camera (NIRCam) in two
filters spanning 3--5 $\mu$m. These data provide the first images of the
system's famous debris disk at these wavelengths and permit additional
constraints on its properties and morphology. Conducting a deep search for
companions in these data, we do not identify any compelling candidates.
However, with sensitivity sufficient to recover planets as small as $\sim 0.1$
Jupiter masses beyond $\sim 2^{\prime\prime}$ ($\sim 20$ au) with $5\sigma$
confidence, these data place significant constraints on any massive companions
that might still remain at large separations and provide additional context for
the compact, multi-planet system orbiting very close-in. The observations
presented here highlight NIRCam's unique capabilities for probing similar disks
in this largely unexplored wavelength range, and provide the deepest direct
imaging constraints on wide-orbit giant planets in this very well studied
benchmark system.
