diff --git a/packages/backend/server/src/plugins/copilot/providers/openai.ts b/packages/backend/server/src/plugins/copilot/providers/openai.ts
index dc2ac8ae9d..c522120df7 100644
--- a/packages/backend/server/src/plugins/copilot/providers/openai.ts
+++ b/packages/backend/server/src/plugins/copilot/providers/openai.ts
@@ -113,8 +113,9 @@ export class OpenAIProvider
             !m ||
             // check content
             typeof m.content !== 'string' ||
-            !m.content ||
-            !m.content.trim()
+            // content and attachments must exist at least one
+            ((!m.content || !m.content.trim()) &&
+              (!Array.isArray(m.attachments) || !m.attachments.length))
         )
       ) {
         throw new Error('Empty message content');
diff --git a/packages/backend/server/src/plugins/copilot/resolver.ts b/packages/backend/server/src/plugins/copilot/resolver.ts
index 222ba7900e..dfd1ded0f3 100644
--- a/packages/backend/server/src/plugins/copilot/resolver.ts
+++ b/packages/backend/server/src/plugins/copilot/resolver.ts
@@ -280,7 +280,10 @@ export class CopilotResolver {
       options.attachments = options.attachments || [];
       const { workspaceId } = session.config;
 
-      for (const blob of await Promise.all(options.blobs)) {
+      const blobs = await Promise.all(options.blobs);
+      delete options.blobs;
+
+      for (const blob of blobs) {
         const uploaded = await this.storage.handleUpload(user.id, blob);
         const link = await this.storage.put(
           user.id,
@@ -289,7 +292,6 @@ export class CopilotResolver {
           uploaded.buffer
         );
         options.attachments.push(link);
-        delete options.blobs;
       }
     }