Assisted-by: Claude Opus 5.5 via Claude Code

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@@ -1,3 +1,8 @@
+> [!NOTE]
+> This repository is archived. The [`kdl`](https://crates.io/crates/kdl)
+> crate has built-in Serde support, on by default, since version 6.6.0.
+> Use that instead.
+
 # serde-kdl2
 
 [Serde](https://serde.rs) integration for [KDL](https://kdl.dev) (KDL Document Language).