What happens under the hood with an ordered transform

I’m having difficulty finding resources that explain exactly what happens under the hood in an ordered transformation.

with pm.Model() as m12_4:
    cutpoints = pm.Normal(
        "cutpoints",
        0.0,
        1.5,
        transform=pm.distributions.transforms.ordered,
        shape=6,
        testval=np.arange(6) - 2.5,
    )

    R = pm.OrderedLogistic("R", 0.0, cutpoints, observed=trolley_df.response.values - 1)