diff --git a/src/webview/host.ts b/src/webview/host.ts
index 3ad3cb7..78b1c8f 100644
--- a/src/webview/host.ts
+++ b/src/webview/host.ts
@@ -154,7 +154,14 @@ export function subscribeToHost(handler: (message: HostToWebview) => void): () =
           type: data.type,
         });
       } else {
-        console.error("[quoll] host message rejected by validator", event.data);
+        // Symmetric with the host-side inbound-validation log (quoll-editor-panel.ts):
+        // preview only type + top-level keys, never the full payload, so an
+        // unvalidated message can't leak arbitrary content to the console.
+        const preview =
+          data !== null && typeof data === "object"
+            ? { type: data.type, keys: Object.keys(data) }
+            : { type: typeof event.data };
+        console.error("[quoll] host message rejected by validator", preview);
       }
       return;
     }
diff --git a/test/webview/host.test.ts b/test/webview/host.test.ts
index 1a9ca59..d92819f 100644
--- a/test/webview/host.test.ts
+++ b/test/webview/host.test.ts
@@ -175,12 +175,18 @@ describe("subscribeToHost — boundary validation + diagnostics", () => {
     expect(detail).toMatchObject({ expected: PROTOCOL_VERSION, got: 2, type: "document" });
   });
 
-  it("rejects and logs a shapeless payload via the validator branch", () => {
-    window.dispatchEvent(new MessageEvent("message", { data: { hello: "world" } }));
+  it("rejects and logs a shapeless payload via the validator branch, previewing only type + keys", () => {
+    window.dispatchEvent(
+      new MessageEvent("message", { data: { hello: "world", secret: "sensitive-value" } })
+    );
 
     expect(handler).not.toHaveBeenCalled();
     expect(errorSpy).toHaveBeenCalledTimes(1);
-    expect(String(errorSpy.mock.calls[0][0])).toContain("rejected by validator");
+    const [message, detail] = errorSpy.mock.calls[0];
+    expect(String(message)).toContain("rejected by validator");
+    expect(detail).toEqual({ type: undefined, keys: ["hello", "secret"] });
+    // The raw payload value must never reach the console — only its shape.
+    expect(JSON.stringify(detail)).not.toContain("sensitive-value");
   });
 
   it("logs an undefined payload as an empty payload, not a validator rejection", () => {