diff --git a/backend/app/routers/jira.py b/backend/app/routers/jira.py
index 2805ebc..ce5be9a 100644
--- a/backend/app/routers/jira.py
+++ b/backend/app/routers/jira.py
@@ -53,7 +53,7 @@ def create_link(
         audit_service.log_action(
             db,
             user_id=user.id,
-            action="jira_link_created",
+            action="JIRA_LINK_CREATED",
             entity_type="jira_link",
             entity_id=str(link.id),
             details={
diff --git a/backend/tests/test_jira_router.py b/backend/tests/test_jira_router.py
new file mode 100644
index 0000000..bb01b0a
--- /dev/null
+++ b/backend/tests/test_jira_router.py
@@ -0,0 +1,68 @@
+"""Jira router API tests (FASE-1.3)."""
+
+import uuid
+
+from app.models.audit import AuditLog
+from app.models.jira_link import JiraLink, JiraLinkEntityType
+
+
+def test_create_link_rejects_invalid_issue_key(client, admin_user, auth_headers):
+    response = client.post(
+        "/api/v1/jira/links",
+        json={
+            "entity_type": "test",
+            "entity_id": str(uuid.uuid4()),
+            "jira_issue_key": "invalid-key",
+        },
+        headers=auth_headers,
+    )
+    # Pydantic validation (422) or global validation handler (400)
+    assert response.status_code in (400, 422)
+
+
+def test_create_link_returns_201(client, admin_user, auth_headers, db):
+    entity_id = uuid.uuid4()
+    response = client.post(
+        "/api/v1/jira/links",
+        json={
+            "entity_type": "test",
+            "entity_id": str(entity_id),
+            "jira_issue_key": "SEC-1234",
+        },
+        headers=auth_headers,
+    )
+    assert response.status_code == 201
+    data = response.json()
+    assert data["jira_issue_key"] == "SEC-1234"
+    assert data["entity_id"] == str(entity_id)
+
+    audit = (
+        db.query(AuditLog)
+        .filter(AuditLog.action == "JIRA_LINK_CREATED")
+        .order_by(AuditLog.timestamp.desc())
+        .first()
+    )
+    assert audit is not None
+    assert audit.details.get("jira_issue_key") == "SEC-1234"
+
+
+def test_list_links_filters_by_entity(client, admin_user, auth_headers, db):
+    entity_id = uuid.uuid4()
+    link = JiraLink(
+        entity_type=JiraLinkEntityType.test,
+        entity_id=entity_id,
+        jira_issue_key="SEC-555",
+        created_by=admin_user.id,
+    )
+    db.add(link)
+    db.commit()
+
+    response = client.get(
+        "/api/v1/jira/links",
+        params={"entity_type": "test", "entity_id": str(entity_id)},
+        headers=auth_headers,
+    )
+    assert response.status_code == 200
+    rows = response.json()
+    assert len(rows) == 1
+    assert rows[0]["jira_issue_key"] == "SEC-555"
diff --git a/backend/tests/test_worklog_service.py b/backend/tests/test_worklog_service.py
new file mode 100644
index 0000000..d70d500
--- /dev/null
+++ b/backend/tests/test_worklog_service.py
@@ -0,0 +1,64 @@
+"""Worklog service tests — integrity hash (FASE-1.5)."""
+
+from datetime import datetime
+from uuid import uuid4
+
+from app.services import worklog_service
+
+
+def test_create_worklog_sets_integrity_hash(db, admin_user):
+    entity_id = uuid4()
+    started = datetime(2026, 5, 18, 9, 0, 0)
+    wl = worklog_service.create_worklog(
+        db,
+        entity_type="test",
+        entity_id=entity_id,
+        user_id=admin_user.id,
+        activity_type="red_team",
+        started_at=started,
+        duration_seconds=3600,
+        description="Manual entry",
+    )
+    db.commit()
+    db.refresh(wl)
+
+    assert wl.integrity_hash
+    assert len(wl.integrity_hash) == 64
+    assert worklog_service.verify_worklog_integrity(wl) is True
+
+
+def test_verify_worklog_integrity_detects_tampering(db, admin_user):
+    wl = worklog_service.create_worklog(
+        db,
+        entity_type="test",
+        entity_id=uuid4(),
+        user_id=admin_user.id,
+        activity_type="blue_validation",
+        started_at=datetime(2026, 5, 18, 10, 0, 0),
+        duration_seconds=1800,
+    )
+    db.commit()
+    db.refresh(wl)
+
+    wl.duration_seconds = 9999
+    assert worklog_service.verify_worklog_integrity(wl) is False
+
+
+def test_list_worklogs_filters_by_entity(db, admin_user):
+    eid = uuid4()
+    worklog_service.create_worklog(
+        db,
+        entity_type="campaign",
+        entity_id=eid,
+        user_id=admin_user.id,
+        activity_type="reporting",
+        started_at=datetime(2026, 5, 18, 11, 0, 0),
+        duration_seconds=600,
+    )
+    db.commit()
+
+    rows = worklog_service.list_worklogs(
+        db, entity_type="campaign", entity_id=eid,
+    )
+    assert len(rows) == 1
+    assert rows[0].entity_id == eid