diff --git a/gso/api/v1/processes.py b/gso/api/v1/processes.py
index 6ad15e91519db09643359614a24ce61587a6739e..a5f120397a57c9fa688e0058719c64c113d34181 100644
--- a/gso/api/v1/processes.py
+++ b/gso/api/v1/processes.py
@@ -3,7 +3,7 @@
 from typing import Any
 from uuid import UUID
 
-from fastapi import APIRouter, HTTPException, status, Depends
+from fastapi import APIRouter, Depends, HTTPException, status
 from orchestrator.db import ProcessStepTable
 from orchestrator.schemas.base import OrchestratorBaseModel
 
diff --git a/gso/middlewares.py b/gso/middlewares.py
index 222f50200ca55aab9d1e5d95fc97a7dd08241c2e..e0d276e3558c72d43127310cdd5576a062cb2be3 100644
--- a/gso/middlewares.py
+++ b/gso/middlewares.py
@@ -61,6 +61,7 @@ class ModifyProcessEndpointResponse(BaseHTTPMiddleware):
         Args:
         ----
             request (Request): The incoming HTTP request.
+
         Returns:
         -------
             str: The token from the request headers in specific format.
@@ -71,8 +72,7 @@ class ModifyProcessEndpointResponse(BaseHTTPMiddleware):
             # Remove the "Bearer " prefix from the token
             token = authorization_header.replace(bearer_prefix, "")
             return f"?token={token}"
-        else:
-            return ""
+        return ""
 
     async def modify_response_body(self, response_body: dict[str, Any], request: Request) -> None:
         """Modify the response body as needed.
diff --git a/test/processes/__init__.py b/test/processes/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/test/processes/conftest.py b/test/processes/conftest.py
new file mode 100644
index 0000000000000000000000000000000000000000..428b0a147c77514e35b1c674499c0eacced44ab2
--- /dev/null
+++ b/test/processes/conftest.py
@@ -0,0 +1 @@
+from test.fixtures import nokia_router_subscription_factory, site_subscription_factory  # noqa: F401
diff --git a/test/processes/test_processes.py b/test/processes/test_processes.py
new file mode 100644
index 0000000000000000000000000000000000000000..671218400c022a96eaa1e119be60db4fa5ec0d7b
--- /dev/null
+++ b/test/processes/test_processes.py
@@ -0,0 +1,49 @@
+from uuid import uuid4
+
+import pytest
+from orchestrator.db import (
+    ProcessStepTable,
+    ProcessSubscriptionTable,
+    ProcessTable,
+    db,
+)
+from orchestrator.workflow import ProcessStatus
+
+
+@pytest.fixture()
+def create_process(faker, nokia_router_subscription_factory):
+    process_id = uuid4()
+    process = ProcessTable(process_id=process_id, workflow_name=faker.sentence(), last_status=ProcessStatus.SUSPENDED)
+    subscription = nokia_router_subscription_factory()
+    process_subscription = ProcessSubscriptionTable(process_id=process_id, subscription_id=subscription)
+
+    db.session.add(process)
+    db.session.add(process_subscription)
+    db.session.commit()
+
+    return process_id
+
+
+def test_callback_results_endpoint(test_client, create_process, faker):
+    expected_result = {"id": 1, "output": faker.sentence()}
+
+    step = ProcessStepTable(
+        process_id=create_process,
+        name="Modify",
+        status="suspend",
+        state={"subscription_id": uuid4(), "callback_result": expected_result},
+    )
+    db.session.add(step)
+    db.session.commit()
+
+    response = test_client.get(f"/api/v1/processes/steps/{step.step_id}/callback-results")
+
+    assert response.status_code == 200
+    assert response.json() == {"callback_results": expected_result}
+
+
+def test_callback_results_endpoint_with_wrong_step_id(test_client):
+    response = test_client.get(f"/api/v1/processes/steps/{uuid4()}/callback-results")
+
+    assert response.status_code == 404
+    assert response.json() == {"detail": "Callback result not found."}