diff --git a/apps/server/src/routes/api/other.ts b/apps/server/src/routes/api/other.ts
index c1a4710b0..e0a9fd4bc 100644
--- a/apps/server/src/routes/api/other.ts
+++ b/apps/server/src/routes/api/other.ts
@@ -31,6 +31,9 @@ function getIconUsage() {
 
 function renderMarkdown(req: Request) {
     const { markdownContent } = req.body;
+    if (!markdownContent || typeof markdownContent !== 'string') {
+        throw new Error('markdownContent parameter is required and must be a string');
+    }
     return {
         htmlContent: markdownService.renderToHtml(markdownContent, "")
     } satisfies RenderMarkdownResponse;
@@ -38,6 +41,9 @@ function renderMarkdown(req: Request) {
 
 function toMarkdown(req: Request) {
     const { htmlContent } = req.body;
+    if (!htmlContent || typeof htmlContent !== 'string') {
+        throw new Error('htmlContent parameter is required and must be a string');
+    }
     return {
         markdownContent: markdown.toMarkdown(htmlContent)
     } satisfies ToMarkdownResponse;