Here is the dump of a SkyWcs constructed using:

import lsst.geom
import lsst.afw.geom

pixelOrigin = lsst.geom.Point2D(100, 100)
skyOrigin = lsst.geom.SpherePoint(0, 45, lsst.geom.degrees)
cdMatrix = lsst.afw.geom.makeCdMatrix(scale=1*lsst.geom.arcseconds)
skyWcs = lsst.afw.geom.makeSkyWcs(pixelOrigin, skyOrigin, cdMatrix)
skyWcs.writeString()

'1 SkyWcs 0  Begin FrameSet
#   Title = "ICRS coordinates; gnomonic projection"
#   Naxes = 2
#   Domain = "SKY"
#   Epoch = 2000
#   Lbl1 = "Right ascension"
#   Lbl2 = "Declination"
#   System = "ICRS"
#   Uni1 = "hh:mm:ss.s"
#   Uni2 = "ddd:mm:ss"
#   Dir1 = 0
#   Bot2 = -1.5707963267948966
#   Top2 = 1.5707963267948966
 IsA Frame
    Nframe = 3
#   Base = 1
    Currnt = 3
    Lnk2 = 1
    Lnk3 = 2
    Frm1 =
       Begin Frame
#         Title = "2-d coordinate system"
          Naxes = 2
          Domain = "PIXELS"
#         Lbl1 = "Axis 1"
#         Lbl2 = "Axis 2"
          Ax1 =
             Begin Axis
             End Axis
          Ax2 =
             Begin Axis
             End Axis
       End Frame
    Frm2 =
       Begin Frame
          Title = "FITS Intermediate World Coordinates"
          Naxes = 2
          Domain = "IWC"
#         Lbl1 = "Axis 1"
#         Lbl2 = "Axis 2"
#         Uni1 = "deg"
#         Uni2 = "deg"
          Ax1 =
             Begin Axis
                Unit = "deg"
             End Axis
          Ax2 =
             Begin Axis
                Unit = "deg"
             End Axis
       End Frame
    Frm3 =
       Begin SkyFrame
          Ident = " "
       IsA Object
#         Title = "ICRS coordinates; gnomonic projection"
          Naxes = 2
#         Domain = "SKY"
          Epoch = 2000
#         Lbl1 = "Right ascension"
#         Lbl2 = "Declination"
          System = "ICRS"
          AlSys = "ICRS"
#         Uni1 = "hh:mm:ss.s"
#         Uni2 = "ddd:mm:ss"
#         Dir1 = 0
#         Bot2 = -1.5707963267948966
#         Top2 = 1.5707963267948966
          Ax1 =
             Begin SkyAxis
             End SkyAxis
          Ax2 =
             Begin SkyAxis
             End SkyAxis
       IsA Frame
          Proj = "gnomonic"
#         SkyTol = 0.001
          Eqnox = 2000
          SRefIs = "Ignored"
          SRef1 = -6.1232339957367673e-17
          SRef2 = 0.78539816339744839
       End SkyFrame
    Map2 =
       Begin WinMap
          Nin = 2
          IsSimp = 1
       IsA Mapping
          Sft1 = 0.027777777777777797
          Scl1 = -0.00027777777777777957
          Sft2 = -0.027777777777777797
          Scl2 = 0.00027777777777777957
       End WinMap
    Map3 =
       Begin CmpMap
          Nin = 2
       IsA Mapping
          InvA = 1
          MapA =
             Begin CmpMap
                Nin = 2
                Invert = 1
             IsA Mapping
                InvA = 1
                MapA =
                   Begin SphMap
                      Nin = 3
                      Nout = 2
                      Invert = 0
                   IsA Mapping
                      UntRd = 1
                      PlrLg = 0
                   End SphMap
                MapB =
                   Begin CmpMap
                      Nin = 3
                      Nout = 2
                   IsA Mapping
                      InvA = 1
                      MapA =
                         Begin MatrixMap
                            Nin = 3
                            Invert = 0
                         IsA Mapping
                            M0 = 0.70710678118654757
                            M1 = 0
                            M2 = 0.70710678118654746
                            M3 = 0
                            M4 = 1
                            M5 = 0
                            M6 = -0.70710678118654746
                            M7 = 0
                            M8 = 0.70710678118654757
                            IM0 = 0.70710678118654757
                            IM1 = 0
                            IM2 = -0.70710678118654746
                            IM3 = 0
                            IM4 = 1
                            IM5 = 0
                            IM6 = 0.70710678118654746
                            IM7 = 0
                            IM8 = 0.70710678118654757
                            Form = "Full"
                         End MatrixMap
                      MapB =
                         Begin CmpMap
                            Nin = 3
                            Nout = 2
                         IsA Mapping
                            MapA =
                               Begin SphMap
                                  Nin = 3
                                  Nout = 2
                                  Invert = 1
                               IsA Mapping
                                  UntRd = 1
                                  PlrLg = 0
                               End SphMap
                            MapB =
                               Begin CmpMap
                                  Nin = 2
                               IsA Mapping
                                  MapA =
                                     Begin WcsMap
                                        Nin = 2
                                        Invert = 1
                                     IsA Mapping
                                        Type = "TAN"
                                     End WcsMap
                                  MapB =
                                     Begin WinMap
                                        Nin = 2
                                        Invert = 0
                                     IsA Mapping
                                        Sft1 = 1.500034664382435e-16
                                        Scl1 = 57.295779513082017
                                        Sft2 = -1.500034664382435e-16
                                        Scl2 = 57.295779513082017
                                     End WinMap
                               End CmpMap
                         End CmpMap
                   End CmpMap
             End CmpMap
          MapB =
             Begin UnitMap
                Nin = 2
                IsSimp = 1
             IsA Mapping
             End UnitMap
       End CmpMap
 End FrameSet
'