From cb1b3afab86031d5b6770460bb67a8b7ac65a65f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rub=C3=A9n=20Rinc=C3=B3n=20Blanco?= <ruben@rinconblanco.es>
Date: Sat, 24 Dec 2022 19:46:45 +0100
Subject: [PATCH] Add note about API not supporting external files (#4483)

---
 docs/API.md | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/docs/API.md b/docs/API.md
index 344960a404b..aa83b7dd12a 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -131,6 +131,15 @@ Libraries can be marked to have their directories available when including their
 supplying the library ids and versions in an array. The id's to supply can be found with the
 `/api/libraries/<language-id>`
 
+Note that using external header files of the type:
+```
+#include <https://some-url.to/a-file.h>
+```
+
+is not supported for this endpoint for security reasons.
+
+The feature for the site is handled client-side, as the compilation nodes have no internet access.
+
 ### `GET /api/formats` - return available code formatters
 
 Returns a list of code formatters. The API returns an array of formatter objects which have the following object