diff --git a/static/js/ui_report.js b/static/js/ui_report.ts
similarity index 73%
rename from static/js/ui_report.js
rename to static/js/ui_report.ts
index d450411ea0..78ae990dd0 100644
--- a/static/js/ui_report.js
+++ b/static/js/ui_report.ts
@@ -10,7 +10,12 @@ import {$t} from "./i18n";
    cls- class that we want to add/remove to/from the status_box
 */
 
-export function message(response_html, status_box, cls = "alert", remove_after) {
+export function message(
+    response_html: string,
+    status_box: JQuery,
+    cls = "alert",
+    remove_after?: number,
+): void {
     // Note we use html() below, since we can rely on our callers escaping HTML
     // via $t_html when interpolating data.
     status_box
@@ -27,7 +32,12 @@ export function message(response_html, status_box, cls = "alert", remove_after)
     status_box.addClass("show");
 }
 
-export function error(response_html, xhr, status_box, remove_after) {
+export function error(
+    response_html: string,
+    xhr: JQuery.jqXHR | undefined,
+    status_box: JQuery,
+    remove_after?: number,
+): void {
     if (xhr && xhr.status >= 400 && xhr.status < 500) {
         // Only display the error response for 4XX, where we've crafted
         // a nice response.
@@ -42,15 +52,19 @@ export function error(response_html, xhr, status_box, remove_after) {
     message(response_html, status_box, "alert-error", remove_after);
 }
 
-export function client_error(response_html, status_box, remove_after) {
+export function client_error(
+    response_html: string,
+    status_box: JQuery,
+    remove_after?: number,
+): void {
     message(response_html, status_box, "alert-error", remove_after);
 }
 
-export function success(response_html, status_box, remove_after) {
+export function success(response_html: string, status_box: JQuery, remove_after?: number): void {
     message(response_html, status_box, "alert-success", remove_after);
 }
 
-export function generic_embed_error(error_html) {
+export function generic_embed_error(error_html: string): void {
     const $alert = $("<div class='alert home-error-bar'></div>");
     const $exit = "<div class='exit'></div>";
 
@@ -59,7 +73,7 @@ export function generic_embed_error(error_html) {
     );
 }
 
-export function generic_row_button_error(xhr, btn) {
+export function generic_row_button_error(xhr: JQuery.jqXHR, btn: JQuery): void {
     if (xhr.status >= 400 && xhr.status < 500) {
         const $error = $("<p>").addClass("text-error").text(JSON.parse(xhr.responseText).msg);
         btn.closest("td").empty().append($error);
@@ -68,13 +82,13 @@ export function generic_row_button_error(xhr, btn) {
     }
 }
 
-export function hide_error($target) {
+export function hide_error($target: JQuery): void {
     $target.addClass("fade-out");
     setTimeout(() => {
         $target.removeClass("show fade-out");
     }, 300);
 }
 
-export function show_error($target) {
+export function show_error($target: JQuery): void {
     $target.addClass("show");
 }
diff --git a/tools/linter_lib/custom_check.py b/tools/linter_lib/custom_check.py
index 4c9a970e6a..779c7c79e0 100644
--- a/tools/linter_lib/custom_check.py
+++ b/tools/linter_lib/custom_check.py
@@ -132,7 +132,7 @@ js_rules = RuleList(
             "exclude": {
                 "static/js/portico",
                 "static/js/lightbox.js",
-                "static/js/ui_report.js",
+                "static/js/ui_report.ts",
                 "static/js/confirm_dialog.js",
                 "frontend_tests/",
             },
diff --git a/tools/test-js-with-node b/tools/test-js-with-node
index 471d3f627d..1187d4fb0c 100755
--- a/tools/test-js-with-node
+++ b/tools/test-js-with-node
@@ -164,7 +164,7 @@ EXEMPT_FILES = {
     "static/js/typing.js",
     "static/js/ui_init.js",
     "static/js/ui.js",
-    "static/js/ui_report.js",
+    "static/js/ui_report.ts",
     "static/js/ui_util.js",
     "static/js/unread_ops.js",
     "static/js/unread_ui.js",