diff --git a/app/config/openapi.js b/app/config/openapi.js
index f0e3151..87006fa 100644
--- a/app/config/openapi.js
+++ b/app/config/openapi.js
@@ -734,6 +734,22 @@ const spec = {
                         // Declare the replay header so SDK generators surface
                         // the field on single-create writes.
                         headers: idempotencyReplayResponseHeader,
+                        // Controller returns `{message, timeEntry}` — same
+                        // envelope drift fixed for /v1/customer in #316.
+                        // Pin the shape so SDK code-gen builds the right
+                        // client type instead of leaving the body
+                        // unspecified.
+                        content: {
+                            'application/json': {
+                                schema: {
+                                    type: 'object',
+                                    properties: {
+                                        message: { type: 'string' },
+                                        timeEntry: { $ref: '#/components/schemas/TimeEntry' },
+                                    },
+                                },
+                            },
+                        },
                     },
                     400: { description: 'Bad request — missing teCustId or teStartedAt' },
                     403: { description: 'Missing or invalid authKey' },
diff --git a/tests/api/openapi.test.js b/tests/api/openapi.test.js
index 2d2f90f..7c33af3 100644
--- a/tests/api/openapi.test.js
+++ b/tests/api/openapi.test.js
@@ -70,6 +70,21 @@ describe('OpenAPI spec', () => {
         expect(schemas.TimeEntry.properties.teStartedAt).toBeDefined();
     });
 
+    test('POST /v1/timeentry 201 declares the {message, timeEntry} envelope', async () => {
+        // Same envelope-drift fix as #316 (customer POST) and #312
+        // (customer GET). Pre-fix the timeentry POST 201 had no
+        // content schema at all, so SDK code-gen modeled the body
+        // as a bare untyped 201 — strictly worse than the customer
+        // case because the row inside the envelope was unreachable
+        // from generated client types.
+        const res = await request(app).get('/openapi.json');
+        const r201 = res.body.paths['/v1/timeentry'].post.responses['201'];
+        const schema = r201.content['application/json'].schema;
+        expect(schema.type).toBe('object');
+        expect(schema.properties.message).toBeDefined();
+        expect(schema.properties.timeEntry.$ref).toBe('#/components/schemas/TimeEntry');
+    });
+
     test('POST /v1/customer 201 declares the {message, customer} envelope', async () => {
         // Same envelope-drift fix as the GET endpoint below (#312)
         // but for the create path. The controller responds with