diff --git a/docs/src/devdocs/FEValues.md b/docs/src/devdocs/FEValues.md
index e329e25c86..3deb8197dd 100644
--- a/docs/src/devdocs/FEValues.md
+++ b/docs/src/devdocs/FEValues.md
@@ -22,7 +22,8 @@ Ferrite.BCValues
 ## Internal utilities
 ```@docs
 Ferrite.embedding_det
-Ferrite.shape_value_type
+Ferrite.shape_value_type(::AbstractValues)
+Ferrite.shape_value_type(::FunctionValues)
 Ferrite.shape_gradient_type
 Ferrite.ValuesUpdateFlags
 ```
diff --git a/docs/src/devdocs/interpolations.md b/docs/src/devdocs/interpolations.md
index 22c45ac3ef..5859861ed2 100644
--- a/docs/src/devdocs/interpolations.md
+++ b/docs/src/devdocs/interpolations.md
@@ -19,6 +19,7 @@ Ferrite.reference_shape_values!
 Ferrite.reference_shape_gradients!
 Ferrite.reference_shape_gradients_and_values!
 Ferrite.reference_shape_hessians_gradients_and_values!
+Ferrite.shape_value_type
 ```
 
 ### Required methods to implement for all subtypes of `Interpolation` to define a new finite element
diff --git a/src/interpolations.jl b/src/interpolations.jl
index daab078a5f..5bed658b22 100644
--- a/src/interpolations.jl
+++ b/src/interpolations.jl
@@ -57,6 +57,11 @@ n_components(::VectorInterpolation{vdim}) where {vdim} = vdim
 # Number of components that are allowed to prescribe in e.g. Dirichlet BC
 n_dbc_components(ip::Interpolation) = n_components(ip)
 
+"""
+    shape_value_type(ip::Iterpolation, ::Type{T}) where T<:Number
+
+Return the type of `shape_value(ip::Interpolation, ξ::Vec, ib::Int)`
+"""
 shape_value_type(::ScalarInterpolation, ::Type{T}) where {T <: Number} = T
 shape_value_type(::VectorInterpolation{vdim}, ::Type{T}) where {vdim, T <: Number} = Vec{vdim, T}
 #shape_value_type(::MatrixInterpolation, T::Type) = Tensor  #958