diff --git a/util/registry/src/entry.rs b/util/registry/src/entry.rs
index 26b97f2b..89379e64 100644
--- a/util/registry/src/entry.rs
+++ b/util/registry/src/entry.rs
@@ -1,3 +1,5 @@
+//! Registry entry types.
+
 use std::{collections::HashSet, hash::Hash, ops::Deref};
 
 use parking_lot::RwLock;
@@ -93,6 +95,7 @@ impl<K, T> RefEntry<K, T> {
     }
 }
 
+/// Guard of tags.
 pub struct TagsGuard<'a, K, T> {
     inner: parking_lot::RwLockReadGuard<'a, HashSet<TagKey<K, T>>>,
 }
diff --git a/util/registry/src/key.rs b/util/registry/src/key.rs
index ff682ddd..a22ede3c 100644
--- a/util/registry/src/key.rs
+++ b/util/registry/src/key.rs
@@ -1,5 +1,9 @@
+//! Registry key related types.
+
 use std::{hash::Hash, marker::PhantomData};
 
+use crate::ProvideRegistry;
+
 /// A key for a value in a registry in a context
 /// where a root registry is available.
 pub struct Key<K, T> {
@@ -81,3 +85,33 @@ impl<K, T> AsRef<K> for Key<K, T> {
         &self.value
     }
 }
+
+#[cfg(feature = "serde")]
+impl<K, T> serde::Serialize for Key<K, T>
+where
+    K: serde::Serialize,
+{
+    #[inline]
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        self.value.serialize(serializer)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl<'r, 'de, K, T> serde::Deserialize<'de> for Key<K, T>
+where
+    K: serde::Deserialize<'de> + Clone + 'r,
+    T: ProvideRegistry<'r, K, T> + 'r,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let registry = T::registry();
+        let value = K::deserialize(deserializer)?;
+        Ok(Self::new(registry.key.value.clone(), value))
+    }
+}
diff --git a/util/registry/src/lib.rs b/util/registry/src/lib.rs
index 33756c6e..43c85b9f 100644
--- a/util/registry/src/lib.rs
+++ b/util/registry/src/lib.rs
@@ -316,6 +316,7 @@ impl<'a, K, T> IntoIterator for &'a Registry<K, T> {
     }
 }
 
+/// Mutable registry of various in-game components.
 pub struct RegistryMut<K, T> {
     key: Key<K, Registry<K, T>>,
     entries: Vec<(T, RefEntry<K, T>)>,
@@ -323,6 +324,7 @@ pub struct RegistryMut<K, T> {
 }
 
 impl<K, T> RegistryMut<K, T> {
+    /// Creates a new mutable registry.
     #[inline]
     pub fn new(key: Key<K, Registry<K, T>>) -> Self {
         Self {
diff --git a/util/registry/src/tag.rs b/util/registry/src/tag.rs
index 4ca14fad..3740fd4b 100644
--- a/util/registry/src/tag.rs
+++ b/util/registry/src/tag.rs
@@ -1,3 +1,5 @@
+//! Tag related types.
+
 use std::{collections::HashMap, hash::Hash};
 
 use crate::{key::Key, Registry};
@@ -99,3 +101,97 @@ impl<'a, K, T> Iterator for Iter<'a, K, T> {
         })
     }
 }
+
+#[cfg(feature = "serde")]
+pub mod serde {
+    //! Helper module for serde support.
+
+    use std::str::FromStr;
+
+    use crate::ProvideRegistry;
+
+    use super::TagKey;
+
+    /// `TagKey` serialize and deserailize wrapper
+    /// without `#` prefix.
+    #[derive(Debug, Clone, Copy)]
+    pub struct Unprefixed<T>(pub T);
+
+    impl<'a, K, T> serde::Serialize for Unprefixed<&'a TagKey<K, T>>
+    where
+        K: serde::Serialize,
+    {
+        #[inline]
+        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+        where
+            S: serde::Serializer,
+        {
+            self.0.id.serialize(serializer)
+        }
+    }
+
+    impl<K, T> serde::Serialize for Unprefixed<TagKey<K, T>>
+    where
+        K: serde::Serialize,
+    {
+        #[inline]
+        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+        where
+            S: serde::Serializer,
+        {
+            Unprefixed(&self.0).serialize(serializer)
+        }
+    }
+
+    impl<'de, 'r, K, T> serde::Deserialize<'de> for Unprefixed<TagKey<K, T>>
+    where
+        K: serde::Deserialize<'de> + Clone + 'r,
+        T: ProvideRegistry<'r, K, T> + 'r,
+    {
+        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+        where
+            D: serde::Deserializer<'de>,
+        {
+            Ok(Unprefixed(TagKey {
+                registry: T::registry().key.clone(),
+                id: K::deserialize(deserializer)?,
+            }))
+        }
+    }
+
+    impl<K, T> serde::Serialize for TagKey<K, T>
+    where
+        K: ToString,
+    {
+        #[inline]
+        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+        where
+            S: serde::Serializer,
+        {
+            format!("#{}", self.id.to_string()).serialize(serializer)
+        }
+    }
+
+    impl<'de, 'r, K, T> serde::Deserialize<'de> for TagKey<K, T>
+    where
+        K: FromStr + Clone + 'r,
+        T: ProvideRegistry<'r, K, T> + 'r,
+        <K as FromStr>::Err: std::fmt::Display,
+    {
+        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+        where
+            D: serde::Deserializer<'de>,
+        {
+            let value = String::deserialize(deserializer)?;
+            let id = value
+                .strip_prefix('#')
+                .ok_or_else(|| serde::de::Error::custom("not a tag key"))?
+                .parse::<K>()
+                .map_err(serde::de::Error::custom)?;
+            Ok(Self {
+                registry: T::registry().key.clone(),
+                id,
+            })
+        }
+    }
+}