diff --git a/src/config.rs b/src/config.rs
index 8a84dff..33b4951 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -13,8 +13,11 @@ pub struct Config {
     pub layouts: Vec<Layout>,
 }
 
+/// A configured layout
 pub struct Layout {
+    /// Layout name
     pub name: String,
+    /// If true, automatically enableable
     pub automatic: bool,
     /// Map of monitor name to OutputConfig
     pub outputs: HashMap<String, OutputConfig>,
diff --git a/src/lid.rs b/src/lid.rs
index 2830979..ddf7bc5 100644
--- a/src/lid.rs
+++ b/src/lid.rs
@@ -3,6 +3,9 @@ use std::io::Read;
 use std::path::PathBuf;
 use crate::config::Monitor;
 
+// Determine if the lid id closed.
+// Returns true if the lid is known to be closed.
+// Returns false if the lid is known to be open, or if the lid state is not known.
 pub fn is_lid_closed(monitor: &Monitor) -> bool {
     if let Some(lid) = &monitor.lid {
         is_acpi_closed(lid)