diff --git a/plugin/rules.ts b/plugin/rules.ts
index ccaacd8..f886f56 100644
--- a/plugin/rules.ts
+++ b/plugin/rules.ts
@@ -25,8 +25,24 @@ export type Decision = {
   reason: string;
 };
 
+/**
+ * Strip trailing OpenClaw metadata blocks from the prompt to get the actual message content.
+ * The prompt format is: [prepend instruction]\n\n[message]\n\nConversation info (untrusted metadata):\n```json\n{...}\n```\n\nSender (untrusted metadata):\n```json\n{...}\n```
+ */
+function stripTrailingMetadata(input: string): string {
+  // Remove all trailing "XXX (untrusted metadata):\n```json\n...\n```" blocks
+  let text = input;
+  // eslint-disable-next-line no-constant-condition
+  while (true) {
+    const m = text.match(/\n*[A-Z][^\n]*\(untrusted metadata\):\s*```json\s*[\s\S]*?```\s*$/);
+    if (!m) break;
+    text = text.slice(0, text.length - m[0].length);
+  }
+  return text;
+}
+
 function getLastChar(input: string): string {
-  const t = input.trim();
+  const t = stripTrailingMetadata(input).trim();
   return t.length ? t[t.length - 1] : "";
 }