diff --git a/.github/.keepalive b/.github/.keepalive
deleted file mode 100644
index 3d5a126..0000000
--- a/.github/.keepalive
+++ /dev/null
@@ -1 +0,0 @@
-2023-06-01T01:10:06.449Z
diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 2b5297f..0c2727b 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -16,6 +16,7 @@ Joey Reed <joeyrreed@gmail.com>
 Jordan-Gallivan <115050475+Jordan-Gallivan@users.noreply.github.com>
 Joris Labie <joris.labie1@gmail.com>
 Justin Dennison <justin1dennison@gmail.com>
+KATTA NAGA NITHIN <88046362+nithinkatta@users.noreply.github.com>
 Marcus <mfantham@users.noreply.github.com>
 Matt Cochrane <matthew.cochrane.eng@gmail.com>
 Milan Raj <rajsite@users.noreply.github.com>
diff --git a/docs/types/index.d.ts b/docs/types/index.d.ts
index 2053c1e..0f58887 100644
--- a/docs/types/index.d.ts
+++ b/docs/types/index.d.ts
@@ -32,7 +32,7 @@
 * var bool = isFunction( beep );
 * // returns true
 */
-declare function isFunction( value: any ): boolean;
+declare function isFunction( value: any ): value is Function;
 
 
 // EXPORTS //