diff --git a/lib/fileset/internal.nix b/lib/fileset/internal.nix
index 546b93f158a1..9892172955c3 100644
--- a/lib/fileset/internal.nix
+++ b/lib/fileset/internal.nix
@@ -172,11 +172,11 @@ rec {
     else if ! isPath value then
       if isStringLike value then
         throw ''
-          ${context} ("${toString value}") is a string-like value, but it should be a path instead.
+          ${context} ("${toString value}") is a string-like value, but it should be a file set or a path instead.
               Paths represented as strings are not supported by `lib.fileset`, use `lib.sources` or derivations instead.''
       else
         throw ''
-          ${context} is of type ${typeOf value}, but it should be a path instead.''
+          ${context} is of type ${typeOf value}, but it should be a file set or a path instead.''
     else if ! pathExists value then
       throw ''
         ${context} (${toString value}) does not exist.''
diff --git a/lib/fileset/tests.sh b/lib/fileset/tests.sh
index 7a104654983f..529f23ae8871 100755
--- a/lib/fileset/tests.sh
+++ b/lib/fileset/tests.sh
@@ -355,8 +355,8 @@ expectFailure 'toSource { root = ./a; fileset = ./.; }' 'lib.fileset.toSource: `
 rm -rf *
 
 # Path coercion only works for paths
-expectFailure 'toSource { root = ./.; fileset = 10; }' 'lib.fileset.toSource: `fileset` is of type int, but it should be a path instead.'
-expectFailure 'toSource { root = ./.; fileset = "/some/path"; }' 'lib.fileset.toSource: `fileset` \("/some/path"\) is a string-like value, but it should be a path instead.
+expectFailure 'toSource { root = ./.; fileset = 10; }' 'lib.fileset.toSource: `fileset` is of type int, but it should be a file set or a path instead.'
+expectFailure 'toSource { root = ./.; fileset = "/some/path"; }' 'lib.fileset.toSource: `fileset` \("/some/path"\) is a string-like value, but it should be a file set or a path instead.
 \s*Paths represented as strings are not supported by `lib.fileset`, use `lib.sources` or derivations instead.'
 
 # Path coercion errors for non-existent paths