diff --git a/packages/SwingSet/misc-tools/classify-promises.js b/packages/SwingSet/misc-tools/classify-promises.js
index 86f1618922e..5074471e2aa 100755
--- a/packages/SwingSet/misc-tools/classify-promises.js
+++ b/packages/SwingSet/misc-tools/classify-promises.js
@@ -429,10 +429,10 @@ const main = rawArgv => {
         for (const [pattern, re] of Object.entries(VAT_NAME_PATTERNS)) {
           const match = vatName && vatName.match(re);
           if (match) {
-            classify(`Zoe E(contractInstanceAdminNode).done()`, {
-              pattern,
-              ...match.groups,
-            });
+            classify(
+              `Zoe E(${pattern} contractInstanceAdminNode).done()`,
+              match.groups,
+            );
             continue nextPromise;
           }
         }