diff --git a/README.md b/README.md
index 4b5a9df52302..e3038706af10 100644
--- a/README.md
+++ b/README.md
@@ -17,6 +17,10 @@ This repo contains automation scripts and CI configuration to run the scripts.
 To run the scripts locally, execute `./ci/<build script>`, where `build script`
 is any executable shell script. Override environment variables as necessary.
 
+### Example: Build user documentations:
+
+    NEOVIM_DIR=~/neovim-src/ ./ci/user-docu.sh
+
 ### Example: Generate the vim-patch report:
 
     VIM_SOURCE_DIR=~/vim-src/ NEOVIM_DIR=~/neovim-src/ ./ci/vimpatch-report.sh
diff --git a/ci/user-docu.sh b/ci/user-docu.sh
index f81a6bfcd185..2612eb3417c5 100755
--- a/ci/user-docu.sh
+++ b/ci/user-docu.sh
@@ -6,6 +6,7 @@ source ${BUILD_DIR}/ci/common/common.sh
 
 generate_user_docu() {
   require_environment_variable BUILD_DIR "${BASH_SOURCE[0]}" ${LINENO}
+  require_environment_variable NEOVIM_DIR "${BASH_SOURCE[0]}" ${LINENO}
 
   cd ${NEOVIM_DIR}
   make