diff --git a/scripts/control-ui-i18n-report.ts b/scripts/control-ui-i18n-report.ts
index 9647f793bd4..85860e24c22 100644
--- a/scripts/control-ui-i18n-report.ts
+++ b/scripts/control-ui-i18n-report.ts
@@ -128,7 +128,7 @@ export function parseArgs(argv: string[]): ReportArgs {
 
 function readOptionValue(argv: string[], index: number, flag: string) {
   const value = argv[index];
-  if (!value || value.startsWith("--")) {
+  if (!value || value.startsWith("-")) {
     throw new Error(`${flag} requires a value`);
   }
   return value;
diff --git a/src/scripts/control-ui-i18n-report.test.ts b/src/scripts/control-ui-i18n-report.test.ts
index 1d414be0b09..579b76c5a21 100644
--- a/src/scripts/control-ui-i18n-report.test.ts
+++ b/src/scripts/control-ui-i18n-report.test.ts
@@ -34,6 +34,13 @@ const entries: RawCopyBaselineEntry[] = [
 ];
 
 describe("control-ui-i18n report helpers", () => {
+  it.each(["--surface", "--locale", "--top"])(
+    "rejects option-shaped values for %s",
+    (flag) => {
+      expect(() => parseArgs([flag, "-h"])).toThrow(`${flag} requires a value`);
+    },
+  );
+
   it("rejects invalid numeric limits", () => {
     expect(() => parseArgs(["--top", "3abc"])).toThrow("--top must be a positive integer");
     expect(() => parseArgs(["--top", "1.5"])).toThrow("--top must be a positive integer");