diff --git a/.clang-uml b/.clang-uml
index 96cff715..af55e480 100644
--- a/.clang-uml
+++ b/.clang-uml
@@ -1,8 +1,8 @@
 compilation_database_dir: debug
 output_directory: docs/diagrams
 generate_links:
-  link: "https://github.com/bkryza/clang-uml/blob/{{ git.commit }}/{{ element.source.path }}#L{{ element.source.line }}"
-  tooltip: "{{ element.name }}"
+  link: 'https://github.com/bkryza/clang-uml/blob/{{ git.commit }}/{{ element.source.path }}#L{{ element.source.line }}'
+  tooltip: '{% if "comment" in element %}{{ abbrv(trim(replace(element.comment, "\n+", " ")), 256) }}{% else %}{{ element.name }}{% endif %}'
 diagrams:
   main_package:
     include!: uml/main_package_diagram.yml
diff --git a/README.md b/README.md
index 2dc93fbb..df3c4bef 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ diagrams:
         - myproject::detail
     plantuml:
       after:
-        - 'note left of @A(MyProjectMain) : Main class of myproject library.'
+        - 'note left of {{ alias("MyProjectMain") }}: Main class of myproject library.'
 ```
 
 See ![here](docs/configuration_file.md) for detailed configuration file reference guide.
diff --git a/docs/configuration_file.md b/docs/configuration_file.md
index 778a8200..ddd9dc82 100644
--- a/docs/configuration_file.md
+++ b/docs/configuration_file.md
@@ -27,6 +27,21 @@
     * `before` - list of directives which will be added before the generated diagram
     * `after` - list of directives which will be added after the generated diagram
 
+### Template engine
+`clang-uml` integrates [inja](https://github.com/pantor/inja) template engine, with several
+additional functions which can be used in textual directives within the configuration files,
+notes and to generate links and tooltips to diagrams.
+
+The following, are the `clang-uml` additional template functions:
+* `ltrim(string)` - left trims a string
+* `rtrim(string)` - right trims a string
+* `trim(string)` - trims a string
+* `substr(string, offset, length)` - returns a substring of a string from offset of length
+* `split(string)` - splits a string and returns a list of strings
+* `replace(string, regex, replacement)` - returns a string with replace matches to regex with replacement string
+* `abbrv(string, length)` - returns a string truncated to length including trailing ellipsis
+* `alias(string)` - returns a PlantUML alias of an C++ entity represented by string name
+
 
 ## Example complete config