diff --git a/src/libcmd/markdown.hh b/src/libcmd/markdown.hh
index a04d32a4f..164f99b98 100644
--- a/src/libcmd/markdown.hh
+++ b/src/libcmd/markdown.hh
@@ -5,6 +5,13 @@
 
 namespace nix {
 
+/**
+ * Render the given Markdown text to the terminal.
+ *
+ * If Nix is compiled without Markdown support, this function will return the input text as-is.
+ *
+ * The renderer takes into account the terminal width, and wraps text accordingly.
+ */
 std::string renderMarkdownToTerminal(std::string_view markdown);
 
 }