diff --git a/backend/app/schemas/todos.py b/backend/app/schemas/todos.py
index 138a7f3..6666bd9 100644
--- a/backend/app/schemas/todos.py
+++ b/backend/app/schemas/todos.py
@@ -1,6 +1,7 @@
 import uuid
 from datetime import datetime
-from pydantic import BaseModel, ConfigDict
+from typing import Literal
+from pydantic import BaseModel, ConfigDict, Field
 
 
 class TodoCreate(BaseModel):
@@ -9,9 +10,9 @@ class TodoCreate(BaseModel):
     url: str | None = None
     domain: str | None = None
     category: str | None = None
-    tags: list[str] = []
-    status: str = "pending"
-    priority: str = "medium"
+    tags: list[str] = Field(default_factory=list)
+    status: Literal["pending", "done", "cancelled"] = "pending"
+    priority: Literal["low", "medium", "high"] = "medium"
     due_date: datetime | None = None
 
 
@@ -22,13 +23,13 @@ class TodoUpdate(BaseModel):
     domain: str | None = None
     category: str | None = None
     tags: list[str] | None = None
-    status: str | None = None
-    priority: str | None = None
+    status: Literal["pending", "done", "cancelled"] | None = None
+    priority: Literal["low", "medium", "high"] | None = None
     due_date: datetime | None = None
 
 
 class PostponeRequest(BaseModel):
-    days: int  # 1 ou 7
+    days: Literal[1, 7]
 
 
 class TodoResponse(BaseModel):
diff --git a/backend/tests/test_todos.py b/backend/tests/test_todos.py
index 177ffdf..83bf50d 100644
--- a/backend/tests/test_todos.py
+++ b/backend/tests/test_todos.py
@@ -47,8 +47,8 @@ async def test_lister_todos_filtre_domaine(client):
 
 
 async def test_mettre_a_jour_todo(client):
-    cr = await client.post("/api/todos/", json={"title": "TEST_avant"})
-    item_id = cr.json()["id"]
+    create_resp = await client.post("/api/todos/", json={"title": "TEST_avant"})
+    item_id = create_resp.json()["id"]
 
     resp = await client.patch(f"/api/todos/{item_id}", json={"title": "TEST_après", "status": "done"})
     assert resp.status_code == 200
@@ -66,8 +66,8 @@ async def test_mettre_a_jour_todo_inexistant(client):
 
 
 async def test_supprimer_todo(client):
-    cr = await client.post("/api/todos/", json={"title": "TEST_à supprimer"})
-    item_id = cr.json()["id"]
+    create_resp = await client.post("/api/todos/", json={"title": "TEST_à supprimer"})
+    item_id = create_resp.json()["id"]
 
     resp = await client.delete(f"/api/todos/{item_id}")
     assert resp.status_code == 204
@@ -78,8 +78,8 @@ async def test_supprimer_todo(client):
 
 async def test_reporter_todo_1_jour(client):
     due = "2026-06-01T10:00:00+00:00"
-    cr = await client.post("/api/todos/", json={"title": "TEST_reporter", "due_date": due})
-    item_id = cr.json()["id"]
+    create_resp = await client.post("/api/todos/", json={"title": "TEST_reporter", "due_date": due})
+    item_id = create_resp.json()["id"]
 
     resp = await client.post(f"/api/todos/{item_id}/postpone", json={"days": 1})
     assert resp.status_code == 200
@@ -90,8 +90,8 @@ async def test_reporter_todo_1_jour(client):
 
 async def test_reporter_todo_1_semaine(client):
     due = "2026-06-01T10:00:00+00:00"
-    cr = await client.post("/api/todos/", json={"title": "TEST_reporter7", "due_date": due})
-    item_id = cr.json()["id"]
+    create_resp = await client.post("/api/todos/", json={"title": "TEST_reporter7", "due_date": due})
+    item_id = create_resp.json()["id"]
 
     resp = await client.post(f"/api/todos/{item_id}/postpone", json={"days": 7})
     assert resp.status_code == 200
@@ -101,8 +101,8 @@ async def test_reporter_todo_1_semaine(client):
 
 
 async def test_reporter_jours_invalides(client):
-    cr = await client.post("/api/todos/", json={"title": "TEST_invalide"})
-    item_id = cr.json()["id"]
+    create_resp = await client.post("/api/todos/", json={"title": "TEST_invalide"})
+    item_id = create_resp.json()["id"]
 
     resp = await client.post(f"/api/todos/{item_id}/postpone", json={"days": 3})
     assert resp.status_code == 422