diff --git a/src/Mod/Part/App/ShapeFix/ShapeFix_EdgePy.xml b/src/Mod/Part/App/ShapeFix/ShapeFix_EdgePy.xml
index f2899e35fc..602230b643 100644
--- a/src/Mod/Part/App/ShapeFix/ShapeFix_EdgePy.xml
+++ b/src/Mod/Part/App/ShapeFix/ShapeFix_EdgePy.xml
@@ -18,37 +18,118 @@
     </Documentation>
     <Methode Name="fixRemovePCurve">
       <Documentation>
-        <UserDocu>Removes pcurve(s) if not matching vertices.</UserDocu>
+        <UserDocu> Removes the pcurve(s) of the edge if it does not match the
+   vertices
+   Check is done
+   Use    : It is to be called when pcurve of an edge can be wrong
+   (e.g., after import from IGES)
+   Returns: True, if does not match, removed (status DONE)
+   False, (status OK) if matches or (status FAIL) if no pcurve,
+   nothing done.</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixRemoveCurve3d">
       <Documentation>
-        <UserDocu>Removes 3d curve if not matching vertices.</UserDocu>
+        <UserDocu>Removes 3d curve of the edge if it does not match the vertices
+   Returns: True,  if does not match, removed (status DONE)
+   False, (status OK) if matches or (status FAIL) if no 3d curve,
+   nothing done.</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixAddPCurve">
       <Documentation>
-        <UserDocu>Adds missing pcurve(s) by projecting 3d curve.</UserDocu>
+        <UserDocu>Adds pcurve(s) of the edge if missing (by projecting 3d curve)
+   Parameter isSeam indicates if the edge is a seam.
+   The parameter 'prec' defines the precision for calculations.
+   If it is 0 (default), the tolerance of the edge is taken.
+   Remark : This method is rather for internal use since it accepts parameter
+   'surfana' for optimization of computations
+   Use    : It is to be called after FixRemovePCurve (if removed) or in any
+   case when edge can have no pcurve
+   Returns: True if pcurve was added, else False
+   Status :
+   OK   : Pcurve exists
+   FAIL1: No 3d curve
+   FAIL2: fail during projecting
+   DONE1: Pcurve was added
+   DONE2: specific case of pcurve going through degenerated point on
+   sphere encountered during projection (see class
+   ShapeConstruct_ProjectCurveOnSurface for more info).</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixAddCurve3d">
       <Documentation>
-        <UserDocu>Tries to build missing 3d curve.</UserDocu>
+        <UserDocu>Tries to build 3d curve of the edge if missing
+   Use    : It is to be called after FixRemoveCurve3d (if removed) or in any
+   case when edge can have no 3d curve
+   Returns: True if 3d curve was added, else False
+   Status :
+   OK   : 3d curve exists
+   FAIL1: BRepLib::BuildCurve3d() has failed
+   DONE1: 3d curve was added.</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixVertexTolerance">
       <Documentation>
-        <UserDocu>Increases tolerances of edge vertices.</UserDocu>
+        <UserDocu>Increases the tolerances of the edge vertices to comprise
+   the ends of 3d curve and pcurve on the given face
+   (first method) or all pcurves stored in an edge (second one)
+   Returns: True, if tolerances have been increased, otherwise False
+   Status:
+   OK   : the original tolerances have not been changed
+   DONE1: the tolerance of first vertex has been increased
+   DONE2: the tolerance of last  vertex has been increased.</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixReversed2d">
       <Documentation>
-        <UserDocu>Fixes edge if pcurve is opposite to 3d curve.</UserDocu>
+        <UserDocu>Fixes edge if pcurve is directed opposite to 3d curve
+   Check is done by call to the function
+   ShapeAnalysis_Edge::CheckCurve3dWithPCurve()
+   Warning: For seam edge this method will check and fix the pcurve in only
+   one direction. Hence, it should be called twice for seam edge:
+   once with edge orientation FORWARD and once with REVERSED.
+   Returns: False if nothing done, True if reversed (status DONE)
+   Status:  OK    - pcurve OK, nothing done
+   FAIL1 - no pcurve
+   FAIL2 - no 3d curve
+   DONE1 - pcurve was reversed.</UserDocu>
       </Documentation>
     </Methode>
     <Methode Name="fixSameParameter">
       <Documentation>
-        <UserDocu>Makes edge SameParameter and sets tolerance.</UserDocu>
+        <UserDocu>Tries to make edge SameParameter and sets corresponding
+   tolerance and SameParameter flag.
+   First, it makes edge same range if SameRange flag is not set.
+   If flag SameParameter is set, this method calls the
+   function ShapeAnalysis_Edge::CheckSameParameter() that
+   calculates the maximal deviation of pcurves of the edge from
+   its 3d curve. If deviation &gt; tolerance, the tolerance of edge
+   is increased to a value of deviation. If deviation &lt; tolerance
+   nothing happens.
+
+   If flag SameParameter is not set, this method chooses the best
+   variant (one that has minimal tolerance), either
+   a. only after computing deviation (as above) or
+   b. after calling standard procedure BRepLib::SameParameter
+   and computing deviation (as above). If 'tolerance' &gt; 0, it is
+   used as parameter for BRepLib::SameParameter, otherwise,
+   tolerance of the edge is used.
+
+   Use    : Is to be called after all pcurves and 3d curve of the edge are
+   correctly computed
+   Remark : SameParameter flag is always set to True after this method
+   Returns: True, if something done, else False
+   Status : OK    - edge was initially SameParameter, nothing is done
+   FAIL1 - computation of deviation of pcurves from 3d curve has failed
+   FAIL2 - BRepLib::SameParameter() has failed
+   DONE1 - tolerance of the edge was increased
+   DONE2 - flag SameParameter was set to True (only if
+   BRepLib::SameParameter() did not set it)
+   DONE3 - edge was modified by BRepLib::SameParameter() to SameParameter
+   DONE4 - not used anymore
+   DONE5 - if the edge resulting from BRepLib has been chosen, i.e. variant b. above
+   (only for edges with not set SameParameter).</UserDocu>
       </Documentation>
     </Methode>
     <ClassDeclarations>