doc: Clarify tree-sitter-hl-mode vs. tree-sitter-langs

Author: ubolonton

doc/emacs-tree-sitter.org

@@ -167,6 +167,7 @@ The variable ~tree-sitter-load-path~ is a list of directories that the function
   (tree-sitter-require 'rust)
 #+end_src
 
+*** tree-sitter-langs
 The package ~tree-sitter-langs~ is a language bundle that contains shared libraries for some languages (as well as syntax highlighting queries). When it is loaded, its shared libraries are prioritized over the CLI's directory.
 
 Syntax-aware language-agnostic mechanisms are meant to be defined by ~tree-sitter-mode~ and its dependent minor modes. They determine the language object to use by consulting the variable ~tree-sitter-major-mode-language-alist~. This list is empty by default, and gets populated by ~tree-sitter-langs~ when it is loaded, and by language major modes that are ~tree-sitter~-aware.
@@ -191,7 +192,7 @@ If, for some reason, you cannot update, the older binaries can be downloaded fro
 :EXPORT_TITLE: Syntax Highlighting
 :END:
 
-Syntax highlighting is provided by the minor mode ~tree-sitter-hl-mode~. It overrides the regex-based highlighting provided by ~font-lock-mode~, using the syntax tree provided by ~tree-sitter-mode~. It is based on [[* Queries][*tree queries*]], a system for pattern-matching on Tree-sitter's syntax trees.
+The minor mode ~tree-sitter-hl-mode~ provides the framework for syntax highlighting. It overrides the regex-based highlighting provided by ~font-lock-mode~, using the syntax tree provided by ~tree-sitter-mode~. It is based on [[* Queries][*tree queries*]], a system for pattern-matching on Tree-sitter's syntax trees.
 
 It can be toggled in a buffer by the command ~tree-sitter-hl-mode~, or enabled through major mode hooks:
 #+begin_src emacs-lisp
@@ -203,6 +204,11 @@ To enable it whenever possible (assuming the language major modes were already i
   (global-tree-sitter-mode)
   (add-hook 'tree-sitter-after-on-hook #'tree-sitter-hl-mode)
 #+end_src
+
+{{% notice info %}}
+Like ~font-lock-mode~, ~tree-sitter-hl-mode~ provides only the mechanisms. The actual highlighting rules are provided by language-specific packages, or a language bundle like ~tree-sitter-langs~.
+{{% /notice %}}
+
 *** tree-sitter-langs
 The package ~tree-sitter-langs~ provides syntax highlighting [[https://github.com/emacs-tree-sitter/tree-sitter-langs/tree/master/queries][queries]] for some languages.