jats:titleAjats:scbstract</jats:sc></jats:title>jats:pWe construct an ambitwistor string that describes Type II supergravity on AdSjats:sub3</jats:sub>jats:italic×</jats:italic>Sjats:sup3</jats:sup>with pure NS flux. The background Einstein equations ensure that the model is anomaly free. The spectrum consists of supergravity fluctuations around this background, with no higher string states. This theory transforms the problem of computingjats:italicn</jats:italic>-point tree-level amplitudes on AdSjats:sub3</jats:sub>into that of understanding anjats:inline-formulajats:alternativesjats:tex-math$$ {\mathfrak{sl}}_2 $$</jats:tex-math><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">mml:msubmml:misl</mml:mi>mml:mn2</mml:mn></mml:msub></mml:math></jats:alternatives></jats:inline-formula>Gaudin integrable system, whose representations are determined by the dual boundary operators and whose spectral parameters correspond to the worldsheet insertion points. The scattering equations take a similar form to flat space, withjats:italicn</jats:italic>(jats:italicn −</jats:italic>3)jats:italic/</jats:italic>2 parametersjats:italicτ</jats:italic>jats:subjats:italicij</jats:italic></jats:sub>parametrizing the eigenvalues of the Gaudin model.</jats:p>