This is the same GET /surveys/fusionMatch endpoint documented under Match API — add offerwall=true to switch it into offerwall mode. It is not re-specified in full here to keep one source of truth; this entry exists so Offerwall has a landing page in the docs tree.
Differences from a normal Match API call when offerwall=true:Returns up to 12 offers instead of 10 (fixed, not configurable via maxNumberOfSurveysReturned)
Applies your account's offerwall filters — minCpi/maxLoi are only honored if isMinCpiEnabled/isMaxLoiEnabled are turned on for offerwall specifically; otherwise they're silently ignored even if passed
Render the returned offers yourself, or point respondents at PureSpectrum's hosted offerwall page (ask your account manager for that URL)