diff --git a/doc/api/errors.md b/doc/api/errors.md
index 5c593e0fcd1b95..936cac77f77d8a 100644
--- a/doc/api/errors.md
+++ b/doc/api/errors.md
@@ -1843,6 +1843,14 @@ unknown file extension.
 
 Creation of a [`zlib`][] object failed due to incorrect configuration.
 
+<a id="HPE_HEADER_OVERFLOW"></a>
+### HPE_HEADER_OVERFLOW
+
+Too much HTTP header data was received. In order to protect against malicious or
+malconfigured clients, if more than 80KB of HTTP header data is received then
+HTTP parsing will abort without a request or response object being created, and
+an `Error` with this code will be emitted.
+
 <a id="MODULE_NOT_FOUND"></a>
 ### MODULE_NOT_FOUND