diff --git a/Core/Residual/VarianceFunctions.h b/Core/Residual/VarianceFunctions.h
index 833f5f72f3bdc419a8fe757b02b4f2653308af85..d9cb2fc03b9fb788e6e119025e764bd6e6b76b92 100644
--- a/Core/Residual/VarianceFunctions.h
+++ b/Core/Residual/VarianceFunctions.h
@@ -15,6 +15,8 @@
 #ifndef BORNAGAIN_DEVICE_INSTRUMENT_VARIANCEFUNCTIONS_H
 #define BORNAGAIN_DEVICE_INSTRUMENT_VARIANCEFUNCTIONS_H
 
+#ifndef USER_API
+
 //! Variance function interface.
 //! @ingroup fitting_internal
 
@@ -28,6 +30,7 @@ public:
     virtual IVarianceFunction* clone() const = 0;
     virtual double variance(double real_value, double simulated_value) const = 0;
 };
+#endif // USER_API
 
 //! Returns 1.0 as variance value
 //! @ingroup fitting
diff --git a/Fit/Minimizer/IMinimizer.h b/Fit/Minimizer/IMinimizer.h
index 8c6e7f7bbc8ca5e0051ca2bdd5f26c85e6be9968..3df9cff885d0605225f280067244a3262f5aaea5 100644
--- a/Fit/Minimizer/IMinimizer.h
+++ b/Fit/Minimizer/IMinimizer.h
@@ -12,6 +12,7 @@
 //
 //  ************************************************************************************************
 
+#ifndef USER_API
 #ifndef BORNAGAIN_FIT_MINIMIZER_IMINIMIZER_H
 #define BORNAGAIN_FIT_MINIMIZER_IMINIMIZER_H
 
@@ -60,3 +61,4 @@ public:
 };
 
 #endif // BORNAGAIN_FIT_MINIMIZER_IMINIMIZER_H
+#endif // USER_API
diff --git a/auto/Wrap/doxygenDevice.i b/auto/Wrap/doxygenDevice.i
index f3966bd3db5ec507b6452b120fa1eff7abcbbe75..2f7c01ec186730b9d22ffeb1eee6f611ca1049b0 100644
--- a/auto/Wrap/doxygenDevice.i
+++ b/auto/Wrap/doxygenDevice.i
@@ -31,7 +31,7 @@ C++ includes: SimulationResult.h
 // File: classBeam.xml
 %feature("docstring") Beam "
 
-Beam defined by wavelength, direction and intensity.
+An incident neutron or x-ray beam.
 
 C++ includes: Beam.h
 ";
@@ -386,7 +386,7 @@ returns true if has masks
 // File: classEllipse.xml
 %feature("docstring") Ellipse "
 
-Ellipse shape.
+An ellipse, for use in detector masks.
 
 C++ includes: Ellipse.h
 ";
@@ -444,7 +444,9 @@ Returns true if area defined by two bins is inside or on border of ellipse; more
 // File: classFootprintGauss.xml
 %feature("docstring") FootprintGauss "
 
-Calculates footprint coefficient for a gaussian beam  Beam width is interpreted as the full width on the level of  \\\\[ \\\\exp{-1/2} \\\\] from the peak intensity.
+Gaussian beam footprint.
+
+Beam width is the full width at half maximum.
 
 C++ includes: FootprintGauss.h
 ";
@@ -473,7 +475,7 @@ Calculate footprint correction coefficient from the beam incident angle  alpha.
 // File: classFootprintSquare.xml
 %feature("docstring") FootprintSquare "
 
-Calculates footprint coefficient for a square beam
+Rectangular beam footprint.
 
 C++ includes: FootprintSquare.h
 ";
@@ -1284,7 +1286,7 @@ Loads histogram from file, the shape of array in file should match Following for
 // File: classInfinitePlane.xml
 %feature("docstring") InfinitePlane "
 
-The infinite plane is used for masking everything once and forever.
+The infinite plane is used for masking the entire detector.
 
 C++ includes: InfinitePlane.h
 ";
@@ -1506,7 +1508,7 @@ Creates  OutputData array in converter units.
 // File: classLine.xml
 %feature("docstring") Line "
 
-A line segment.
+A line segment, for use in detector masks.
 
 C++ includes: Line.h
 ";
@@ -2001,7 +2003,7 @@ C++ includes: OutputDataReadWriteNumpyTXT.h
 // File: classPolygon.xml
 %feature("docstring") Polygon "
 
-A polygon in 2D space.  Polygon defined by two arrays with x and y coordinates of points. Sizes of arrays should coincide. If polygon is unclosed (the last point doesn't repeat the first one), it will be closed automatically.
+A polygon, for use in detector masks.  Polygon defined by two arrays with x and y coordinates of points. Sizes of arrays should coincide. If polygon is unclosed (the last point doesn't repeat the first one), it will be closed automatically.
 
 C++ includes: Polygon.h
 ";
@@ -2071,7 +2073,9 @@ The private data for polygons to hide boost dependency from the header.
 // File: classRectangle.xml
 %feature("docstring") Rectangle "
 
-The rectangle shape having its axis aligned to the (non-rotated) coordinate system.
+A rectangle, for use in detector masks.
+
+Edges are along the coordinate axes.
 
 C++ includes: Rectangle.h
 ";
diff --git a/auto/Wrap/libBornAgainDevice.py b/auto/Wrap/libBornAgainDevice.py
index dfb747dd7c421ee45c037475a73adec5941fd149..e0a6d3ebcae5fa106820e2b1981de06cbcfa5f2e 100644
--- a/auto/Wrap/libBornAgainDevice.py
+++ b/auto/Wrap/libBornAgainDevice.py
@@ -2682,7 +2682,7 @@ class Beam(libBornAgainParam.INode):
     r"""
 
 
-    Beam defined by wavelength, direction and intensity.
+    An incident neutron or x-ray beam.
 
     C++ includes: Beam.h
 
@@ -2913,7 +2913,9 @@ class FootprintGauss(IFootprintFactor):
     r"""
 
 
-    Calculates footprint coefficient for a gaussian beam  Beam width is interpreted as the full width on the level of  \\[ \\exp{-1/2} \\] from the peak intensity.
+    Gaussian beam footprint.
+
+    Beam width is the full width at half maximum.
 
     C++ includes: FootprintGauss.h
 
@@ -2973,7 +2975,7 @@ class FootprintSquare(IFootprintFactor):
     r"""
 
 
-    Calculates footprint coefficient for a square beam
+    Rectangular beam footprint.
 
     C++ includes: FootprintSquare.h
 
@@ -3072,7 +3074,7 @@ class Ellipse(IShape2D):
     r"""
 
 
-    Ellipse shape.
+    An ellipse, for use in detector masks.
 
     C++ includes: Ellipse.h
 
@@ -3174,7 +3176,7 @@ class Line(IShape2D):
     r"""
 
 
-    A line segment.
+    A line segment, for use in detector masks.
 
     C++ includes: Line.h
 
@@ -3334,7 +3336,7 @@ class Polygon(IShape2D):
     r"""
 
 
-    A polygon in 2D space.  Polygon defined by two arrays with x and y coordinates of points. Sizes of arrays should coincide. If polygon is unclosed (the last point doesn't repeat the first one), it will be closed automatically.
+    A polygon, for use in detector masks.  Polygon defined by two arrays with x and y coordinates of points. Sizes of arrays should coincide. If polygon is unclosed (the last point doesn't repeat the first one), it will be closed automatically.
 
     C++ includes: Polygon.h
 
@@ -3396,7 +3398,9 @@ class Rectangle(IShape2D):
     r"""
 
 
-    The rectangle shape having its axis aligned to the (non-rotated) coordinate system.
+    A rectangle, for use in detector masks.
+
+    Edges are along the coordinate axes.
 
     C++ includes: Rectangle.h