diff --git a/tools/manifest-schema/CHANGELOG.md b/tools/manifest-schema/CHANGELOG.md
index 43fe522d..1eff8b87 100644
--- a/tools/manifest-schema/CHANGELOG.md
+++ b/tools/manifest-schema/CHANGELOG.md
@@ -22,6 +22,8 @@ Note: In this file, do not use the hard wrap in the middle of a sentence for com
 
 - Remove `BaseManifest` and related types since they are unrelated to public manifests.
 
+- Enable [release immutability](https://docs.github.com/en/code-security/supply-chain-security/understanding-your-software-supply-chain/immutable-releases).
+
 ## [0.1.1] - 2025-09-20
 
 - Add `HostPlatform::{powerpc64le_linux_gnu,powerpc64le_linux_musl,riscv64_linux_gnu,riscv64_linux_musl,s390x_linux_gnu,s390x_linux_musl}` ([#1133](https://github.com/taiki-e/install-action/pull/1133))