diff --git a/.changeset/pretty-ways-knock.md b/.changeset/pretty-ways-knock.md
new file mode 100644
index 0000000000..1b8d56c178
--- /dev/null
+++ b/.changeset/pretty-ways-knock.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-todo-backend': patch
+---
+
+Fixed a bug where filter queries from the frontend would always fail validation.
diff --git a/plugins/todo-backend/src/schema/openapi.generated.ts b/plugins/todo-backend/src/schema/openapi.generated.ts
index a58a96ddb8..effe851790 100644
--- a/plugins/todo-backend/src/schema/openapi.generated.ts
+++ b/plugins/todo-backend/src/schema/openapi.generated.ts
@@ -173,6 +173,7 @@ export const spec = {
             name: 'filter',
             in: 'query',
             required: false,
+            allowReserved: true,
             schema: {
               type: 'array',
               description:
diff --git a/plugins/todo-backend/src/schema/openapi.yaml b/plugins/todo-backend/src/schema/openapi.yaml
index 0e6203e002..8023144f48 100644
--- a/plugins/todo-backend/src/schema/openapi.yaml
+++ b/plugins/todo-backend/src/schema/openapi.yaml
@@ -111,6 +111,7 @@ paths:
         - name: filter
           in: query
           required: false
+          allowReserved: true
           schema:
             type: array
             description: A list of filters used to narrow down the listed TODO items
diff --git a/plugins/todo-backend/src/service/router.test.ts b/plugins/todo-backend/src/service/router.test.ts
index 0bf591316c..64f894a147 100644
--- a/plugins/todo-backend/src/service/router.test.ts
+++ b/plugins/todo-backend/src/service/router.test.ts
@@ -131,6 +131,23 @@ describe('createRouter', () => {
       );
     });
 
+    it('forwards filter query', async () => {
+      mockService.listTodos.mockResolvedValueOnce(mockListBody);
+
+      const response = await request(app).get('/v1/todos?filter=text=*borked*');
+      expect(response.status).toEqual(200);
+      expect(response.body).toEqual(mockListBody);
+      expect(mockService.listTodos).toHaveBeenCalledWith(
+        {
+          entity: undefined,
+          offset: undefined,
+          limit: undefined,
+          filters: [{ field: 'text', value: '*borked*' }],
+        },
+        { token: undefined },
+      );
+    });
+
     it('rejects invalid queries', async () => {
       request(app)
         .get('/v1/todos?entity=k:n&entity=k:n')