diff --git a/logger.ts b/logger.ts
index d147802..91956a4 100644
--- a/logger.ts
+++ b/logger.ts
@@ -1,6 +1,20 @@
 import * as log from "log/mod.ts";
 import { isDenoDeploy } from "./utils.ts";
 
+const getArgStr = (arg: unknown) => {
+  if (Array.isArray(arg)) {
+    return arg.join(", ");
+  }
+  if (typeof arg === "object") {
+    try {
+      return JSON.stringify(arg, null, 2);
+    } catch (_e) {
+      return arg?.toString() ?? arg;
+    }
+  }
+  return arg;
+};
+
 log.setup({
   handlers: {
     console: new log.handlers.ConsoleHandler("DEBUG", {
@@ -8,7 +22,7 @@ log.setup({
         let msg = `${logRecord.levelName} ${logRecord.msg}`;
 
         logRecord.args.forEach((arg, index) => {
-          msg += `, arg${index}: ${arg}`;
+          msg += `, arg${index}: ${getArgStr(arg)}`;
         });
 
         return msg;