  The advantage of having a high-fidelity instrument simulation tool developed
in tandem with novel instrumentation is having the ability to investigate, in
isolation and in combination, the wide parameter space set by the instrument
design. SCALES, the third generation thermal-infrared diffraction limited
imager and low/med-resolution integral field spectrograph being designed for
Keck, is an instrument unique in design in order to optimize for its driving
science case of direct detection and characterization of thermal emission from
cold exoplanets. This warranted an end-to-end simulation tool that
systematically produces realistic mock data from SCALES to probe the recovery
of injected signals under changes in instrument design parameters. In this
paper, we quantify optomechanical tolerance and detector electronic
requirements set by the fiducial science cases using information content
analysis, and test the consequences of updates to the design of the instrument
on meeting these requirements.
