diff --git a/tests/api/test_collections.py b/tests/api/test_collections.py
new file mode 100644
index 0000000..740640f
--- /dev/null
+++ b/tests/api/test_collections.py
@@ -0,0 +1,620 @@
+import pytest
+from fastapi.testclient import TestClient
+from bson import ObjectId
+from datetime import datetime
+
+from src.models.team import TeamModel
+from src.models.user import UserModel
+from src.models.image import ImageModel
+
+
+class CollectionModel:
+    """Mock collection model for testing"""
+    def __init__(self, **kwargs):
+        self.id = kwargs.get('id', ObjectId())
+        self.name = kwargs.get('name')
+        self.description = kwargs.get('description')
+        self.team_id = kwargs.get('team_id')
+        self.created_by = kwargs.get('created_by')
+        self.created_at = kwargs.get('created_at', datetime.utcnow())
+        self.updated_at = kwargs.get('updated_at', datetime.utcnow())
+        self.metadata = kwargs.get('metadata', {})
+        self.image_count = kwargs.get('image_count', 0)
+
+
+@pytest.mark.asyncio
+async def test_create_collection(client: TestClient, admin_api_key: tuple, test_team: TeamModel):
+    """Test creating a new image collection"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers with the admin API key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a new collection
+    response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Test Collection",
+            "description": "A collection for testing images",
+            "metadata": {
+                "category": "test",
+                "project": "sereact"
+            }
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 201
+    data = response.json()
+    assert "id" in data
+    assert data["name"] == "Test Collection"
+    assert data["description"] == "A collection for testing images"
+    assert data["team_id"] == str(test_team.id)
+    assert "created_at" in data
+    assert data["image_count"] == 0
+
+
+@pytest.mark.asyncio
+async def test_create_collection_non_admin(client: TestClient, user_api_key: tuple):
+    """Test that regular users can create collections"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers with a regular user API key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a new collection
+    response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "User Collection",
+            "description": "A collection created by a regular user"
+        }
+    )
+    
+    # Check response - regular users should be able to create collections
+    assert response.status_code == 201
+    data = response.json()
+    assert data["name"] == "User Collection"
+
+
+@pytest.mark.asyncio
+async def test_list_collections(client: TestClient, admin_api_key: tuple, test_team: TeamModel):
+    """Test listing collections for a team"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # List collections
+    response = client.get(
+        "/api/v1/collections",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "collections" in data
+    assert "total" in data
+    assert isinstance(data["collections"], list)
+
+
+@pytest.mark.asyncio
+async def test_get_collection_by_id(client: TestClient, admin_api_key: tuple):
+    """Test getting a specific collection by ID"""
+    raw_key, _ = admin_api_key
+    
+    # First create a collection
+    headers = {"X-API-Key": raw_key}
+    
+    create_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Get Test Collection",
+            "description": "Collection for get testing"
+        }
+    )
+    
+    assert create_response.status_code == 201
+    collection_id = create_response.json()["id"]
+    
+    # Get the collection
+    response = client.get(
+        f"/api/v1/collections/{collection_id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["id"] == collection_id
+    assert data["name"] == "Get Test Collection"
+    assert data["description"] == "Collection for get testing"
+
+
+@pytest.mark.asyncio
+async def test_update_collection(client: TestClient, admin_api_key: tuple):
+    """Test updating a collection"""
+    raw_key, _ = admin_api_key
+    
+    # First create a collection
+    headers = {"X-API-Key": raw_key}
+    
+    create_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Update Test Collection",
+            "description": "Collection for update testing"
+        }
+    )
+    
+    assert create_response.status_code == 201
+    collection_id = create_response.json()["id"]
+    
+    # Update the collection
+    response = client.put(
+        f"/api/v1/collections/{collection_id}",
+        headers=headers,
+        json={
+            "name": "Updated Collection Name",
+            "description": "This collection has been updated",
+            "metadata": {
+                "updated": True,
+                "version": 2
+            }
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["id"] == collection_id
+    assert data["name"] == "Updated Collection Name"
+    assert data["description"] == "This collection has been updated"
+    assert data["metadata"]["updated"] is True
+    assert "updated_at" in data
+
+
+@pytest.mark.asyncio
+async def test_delete_collection(client: TestClient, admin_api_key: tuple):
+    """Test deleting a collection"""
+    raw_key, _ = admin_api_key
+    
+    # First create a collection
+    headers = {"X-API-Key": raw_key}
+    
+    create_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Delete Test Collection",
+            "description": "Collection for delete testing"
+        }
+    )
+    
+    assert create_response.status_code == 201
+    collection_id = create_response.json()["id"]
+    
+    # Delete the collection
+    response = client.delete(
+        f"/api/v1/collections/{collection_id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 204
+    
+    # Verify collection is deleted
+    get_response = client.get(
+        f"/api/v1/collections/{collection_id}",
+        headers=headers
+    )
+    assert get_response.status_code == 404
+
+
+@pytest.mark.asyncio
+async def test_add_image_to_collection(client: TestClient, admin_api_key: tuple):
+    """Test adding an image to a collection"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Image Collection",
+            "description": "Collection for image testing"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Mock image ID (in real implementation, this would be from uploaded image)
+    image_id = str(ObjectId())
+    
+    # Add image to collection
+    response = client.post(
+        f"/api/v1/collections/{collection_id}/images",
+        headers=headers,
+        json={
+            "image_id": image_id
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "success" in data
+    assert data["success"] is True
+
+
+@pytest.mark.asyncio
+async def test_remove_image_from_collection(client: TestClient, admin_api_key: tuple):
+    """Test removing an image from a collection"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Remove Image Collection",
+            "description": "Collection for image removal testing"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Mock image ID
+    image_id = str(ObjectId())
+    
+    # Add image to collection first
+    add_response = client.post(
+        f"/api/v1/collections/{collection_id}/images",
+        headers=headers,
+        json={"image_id": image_id}
+    )
+    assert add_response.status_code == 200
+    
+    # Remove image from collection
+    response = client.delete(
+        f"/api/v1/collections/{collection_id}/images/{image_id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["success"] is True
+
+
+@pytest.mark.asyncio
+async def test_list_images_in_collection(client: TestClient, admin_api_key: tuple):
+    """Test listing images in a collection"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "List Images Collection",
+            "description": "Collection for listing images"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # List images in collection
+    response = client.get(
+        f"/api/v1/collections/{collection_id}/images",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "images" in data
+    assert "total" in data
+    assert isinstance(data["images"], list)
+
+
+@pytest.mark.asyncio
+async def test_collection_access_control(client: TestClient, user_api_key: tuple):
+    """Test that users can only access collections from their team"""
+    raw_key, _ = user_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to access a collection from another team
+    other_collection_id = str(ObjectId())
+    
+    response = client.get(
+        f"/api/v1/collections/{other_collection_id}",
+        headers=headers
+    )
+    
+    # Should return 403 or 404 depending on implementation
+    assert response.status_code in [403, 404]
+
+
+@pytest.mark.asyncio
+async def test_collection_pagination(client: TestClient, admin_api_key: tuple):
+    """Test collection listing with pagination"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Test pagination
+    response = client.get(
+        "/api/v1/collections?page=1&limit=10",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "collections" in data
+    assert "pagination" in data
+    assert "total" in data["pagination"]
+    assert "page" in data["pagination"]
+    assert "pages" in data["pagination"]
+    assert len(data["collections"]) <= 10
+
+
+@pytest.mark.asyncio
+async def test_collection_search(client: TestClient, admin_api_key: tuple):
+    """Test searching collections by name or description"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection with searchable content
+    create_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Searchable Collection",
+            "description": "This collection contains vacation photos"
+        }
+    )
+    assert create_response.status_code == 201
+    
+    # Search for collections
+    response = client.get(
+        "/api/v1/collections/search?query=vacation",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "collections" in data
+    assert "total" in data
+    
+    # Results should contain collections matching the query
+    for collection in data["collections"]:
+        assert ("vacation" in collection["name"].lower() or 
+                "vacation" in collection["description"].lower())
+
+
+@pytest.mark.asyncio
+async def test_collection_statistics(client: TestClient, admin_api_key: tuple):
+    """Test getting collection statistics"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Stats Collection",
+            "description": "Collection for statistics testing"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Get collection statistics
+    response = client.get(
+        f"/api/v1/collections/{collection_id}/stats",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "image_count" in data
+    assert "total_size" in data
+    assert "created_at" in data
+    assert "last_updated" in data
+
+
+@pytest.mark.asyncio
+async def test_bulk_add_images_to_collection(client: TestClient, admin_api_key: tuple):
+    """Test adding multiple images to a collection at once"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Bulk Add Collection",
+            "description": "Collection for bulk operations"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Mock multiple image IDs
+    image_ids = [str(ObjectId()) for _ in range(5)]
+    
+    # Bulk add images to collection
+    response = client.post(
+        f"/api/v1/collections/{collection_id}/images/bulk",
+        headers=headers,
+        json={
+            "image_ids": image_ids
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "added_count" in data
+    assert data["added_count"] == 5
+
+
+@pytest.mark.asyncio
+async def test_collection_export(client: TestClient, admin_api_key: tuple):
+    """Test exporting collection metadata"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Export Collection",
+            "description": "Collection for export testing",
+            "metadata": {"category": "test", "project": "sereact"}
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Export collection
+    response = client.get(
+        f"/api/v1/collections/{collection_id}/export",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "collection" in data
+    assert "images" in data
+    assert data["collection"]["name"] == "Export Collection"
+
+
+@pytest.mark.asyncio
+async def test_collection_duplicate_name_validation(client: TestClient, admin_api_key: tuple):
+    """Test that duplicate collection names within a team are handled"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create first collection
+    response1 = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Duplicate Name Collection",
+            "description": "First collection with this name"
+        }
+    )
+    assert response1.status_code == 201
+    
+    # Try to create second collection with same name
+    response2 = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Duplicate Name Collection",
+            "description": "Second collection with same name"
+        }
+    )
+    
+    # Should either allow it or reject it depending on business rules
+    # For now, let's assume it's allowed but with different handling
+    assert response2.status_code in [201, 400]
+
+
+@pytest.mark.asyncio
+async def test_collection_metadata_validation(client: TestClient, admin_api_key: tuple):
+    """Test validation of collection metadata"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Test with invalid metadata structure
+    response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Invalid Metadata Collection",
+            "description": "Collection with invalid metadata",
+            "metadata": "invalid_metadata_type"  # Should be dict
+        }
+    )
+    
+    # Should validate metadata structure
+    assert response.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_collection_ownership_transfer(client: TestClient, admin_api_key: tuple):
+    """Test transferring collection ownership (admin only)"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a collection
+    collection_response = client.post(
+        "/api/v1/collections",
+        headers=headers,
+        json={
+            "name": "Transfer Collection",
+            "description": "Collection for ownership transfer"
+        }
+    )
+    collection_id = collection_response.json()["id"]
+    
+    # Transfer ownership to another user
+    new_owner_id = str(ObjectId())
+    response = client.put(
+        f"/api/v1/collections/{collection_id}/owner",
+        headers=headers,
+        json={
+            "new_owner_id": new_owner_id
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["created_by"] == new_owner_id
+
+
+@pytest.mark.asyncio
+async def test_invalid_collection_id(client: TestClient, admin_api_key: tuple):
+    """Test handling of invalid collection IDs"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to get collection with invalid ID
+    response = client.get(
+        "/api/v1/collections/invalid-id",
+        headers=headers
+    )
+    
+    # Check that the request returns 400 Bad Request
+    assert response.status_code == 400
+    assert "detail" in response.json()
+
+
+@pytest.mark.asyncio
+async def test_nonexistent_collection(client: TestClient, admin_api_key: tuple):
+    """Test handling of nonexistent collection IDs"""
+    raw_key, _ = admin_api_key
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to get nonexistent collection
+    nonexistent_id = str(ObjectId())
+    response = client.get(
+        f"/api/v1/collections/{nonexistent_id}",
+        headers=headers
+    )
+    
+    # Check that the request returns 404 Not Found
+    assert response.status_code == 404
+    assert "detail" in response.json() 
\ No newline at end of file
diff --git a/tests/api/test_users.py b/tests/api/test_users.py
new file mode 100644
index 0000000..8d6010f
--- /dev/null
+++ b/tests/api/test_users.py
@@ -0,0 +1,549 @@
+import pytest
+from fastapi.testclient import TestClient
+from bson import ObjectId
+
+from src.models.user import UserModel
+from src.models.team import TeamModel
+from src.db.repositories.user_repository import user_repository
+from src.db.repositories.team_repository import team_repository
+
+
+@pytest.mark.asyncio
+async def test_create_user(client: TestClient, admin_api_key: tuple, test_team: TeamModel):
+    """Test creating a new user (admin only)"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers with the admin API key
+    headers = {"X-API-Key": raw_key}
+    
+    # Create a new user
+    response = client.post(
+        "/api/v1/users",
+        headers=headers,
+        json={
+            "email": "newuser@example.com",
+            "name": "New User",
+            "team_id": str(test_team.id),
+            "is_admin": False
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 201
+    data = response.json()
+    assert "id" in data
+    assert data["email"] == "newuser@example.com"
+    assert data["name"] == "New User"
+    assert data["team_id"] == str(test_team.id)
+    assert data["is_admin"] is False
+    assert "created_at" in data
+
+
+@pytest.mark.asyncio
+async def test_create_user_non_admin(client: TestClient, user_api_key: tuple, test_team: TeamModel):
+    """Test that non-admin users cannot create users"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers with a non-admin API key
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to create a new user
+    response = client.post(
+        "/api/v1/users",
+        headers=headers,
+        json={
+            "email": "unauthorized@example.com",
+            "name": "Unauthorized User",
+            "team_id": str(test_team.id),
+            "is_admin": False
+        }
+    )
+    
+    # Check that the request is forbidden
+    assert response.status_code == 403
+    assert "detail" in response.json()
+    assert "admin" in response.json()["detail"].lower()
+
+
+@pytest.mark.asyncio
+async def test_list_users_in_team(client: TestClient, admin_api_key: tuple, test_team: TeamModel):
+    """Test listing users in a team"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # List users in the team
+    response = client.get(
+        f"/api/v1/users?team_id={test_team.id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "users" in data
+    assert "total" in data
+    assert data["total"] >= 1  # Should include at least the admin user
+
+
+@pytest.mark.asyncio
+async def test_list_all_users_admin_only(client: TestClient, admin_api_key: tuple):
+    """Test that only admins can list all users across teams"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # List all users (no team filter)
+    response = client.get(
+        "/api/v1/users",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "users" in data
+    assert "total" in data
+
+
+@pytest.mark.asyncio
+async def test_list_users_non_admin_restricted(client: TestClient, user_api_key: tuple):
+    """Test that non-admin users can only see their own team"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to list all users
+    response = client.get(
+        "/api/v1/users",
+        headers=headers
+    )
+    
+    # Should only return users from their own team
+    assert response.status_code == 200
+    data = response.json()
+    assert "users" in data
+    # All returned users should be from the same team
+    if data["users"]:
+        user_team_ids = set(user["team_id"] for user in data["users"])
+        assert len(user_team_ids) == 1  # Only one team represented
+
+
+@pytest.mark.asyncio
+async def test_get_user_by_id(client: TestClient, admin_api_key: tuple, admin_user: UserModel):
+    """Test getting a specific user by ID"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Get the user
+    response = client.get(
+        f"/api/v1/users/{admin_user.id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["id"] == str(admin_user.id)
+    assert data["email"] == admin_user.email
+    assert data["name"] == admin_user.name
+    assert data["team_id"] == str(admin_user.team_id)
+    assert data["is_admin"] == admin_user.is_admin
+
+
+@pytest.mark.asyncio
+async def test_get_user_self(client: TestClient, user_api_key: tuple, regular_user: UserModel):
+    """Test that users can get their own information"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Get own user information
+    response = client.get(
+        f"/api/v1/users/{regular_user.id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["id"] == str(regular_user.id)
+    assert data["email"] == regular_user.email
+
+
+@pytest.mark.asyncio
+async def test_get_user_other_team_forbidden(client: TestClient, user_api_key: tuple):
+    """Test that users cannot access users from other teams"""
+    raw_key, _ = user_api_key
+    
+    # Create a user in another team
+    other_team = TeamModel(
+        name="Other Team",
+        description="Another team for testing"
+    )
+    created_team = await team_repository.create(other_team)
+    
+    other_user = UserModel(
+        email="other@example.com",
+        name="Other User",
+        team_id=created_team.id,
+        is_admin=False
+    )
+    created_user = await user_repository.create(other_user)
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to get the other user
+    response = client.get(
+        f"/api/v1/users/{created_user.id}",
+        headers=headers
+    )
+    
+    # Check that the request is forbidden
+    assert response.status_code == 403
+    assert "detail" in response.json()
+
+
+@pytest.mark.asyncio
+async def test_update_user(client: TestClient, admin_api_key: tuple, regular_user: UserModel):
+    """Test updating a user (admin only)"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Update the user
+    response = client.put(
+        f"/api/v1/users/{regular_user.id}",
+        headers=headers,
+        json={
+            "name": "Updated User Name",
+            "email": "updated@example.com",
+            "is_admin": True
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["id"] == str(regular_user.id)
+    assert data["name"] == "Updated User Name"
+    assert data["email"] == "updated@example.com"
+    assert data["is_admin"] is True
+    assert "updated_at" in data
+
+
+@pytest.mark.asyncio
+async def test_update_user_self(client: TestClient, user_api_key: tuple, regular_user: UserModel):
+    """Test that users can update their own basic information"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Update own information (limited fields)
+    response = client.put(
+        f"/api/v1/users/{regular_user.id}",
+        headers=headers,
+        json={
+            "name": "Self Updated Name",
+            "email": "self_updated@example.com"
+            # Note: is_admin should not be updatable by self
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["name"] == "Self Updated Name"
+    assert data["email"] == "self_updated@example.com"
+    # Admin status should remain unchanged
+    assert data["is_admin"] == regular_user.is_admin
+
+
+@pytest.mark.asyncio
+async def test_update_user_non_admin_forbidden(client: TestClient, user_api_key: tuple, admin_user: UserModel):
+    """Test that non-admin users cannot update other users"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to update another user
+    response = client.put(
+        f"/api/v1/users/{admin_user.id}",
+        headers=headers,
+        json={
+            "name": "Unauthorized Update",
+            "is_admin": False
+        }
+    )
+    
+    # Check that the request is forbidden
+    assert response.status_code == 403
+    assert "detail" in response.json()
+
+
+@pytest.mark.asyncio
+async def test_delete_user(client: TestClient, admin_api_key: tuple):
+    """Test deleting a user (admin only)"""
+    raw_key, _ = admin_api_key
+    
+    # Create a user to delete
+    user_to_delete = UserModel(
+        email="delete@example.com",
+        name="User to Delete",
+        team_id=ObjectId(),
+        is_admin=False
+    )
+    created_user = await user_repository.create(user_to_delete)
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Delete the user
+    response = client.delete(
+        f"/api/v1/users/{created_user.id}",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 204
+    
+    # Verify the user has been deleted
+    deleted_user = await user_repository.get_by_id(created_user.id)
+    assert deleted_user is None
+
+
+@pytest.mark.asyncio
+async def test_delete_user_non_admin(client: TestClient, user_api_key: tuple, admin_user: UserModel):
+    """Test that non-admin users cannot delete users"""
+    raw_key, _ = user_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to delete a user
+    response = client.delete(
+        f"/api/v1/users/{admin_user.id}",
+        headers=headers
+    )
+    
+    # Check that the request is forbidden
+    assert response.status_code == 403
+    assert "detail" in response.json()
+    assert "admin" in response.json()["detail"].lower()
+
+
+@pytest.mark.asyncio
+async def test_get_user_activity(client: TestClient, admin_api_key: tuple, regular_user: UserModel):
+    """Test getting user activity/statistics"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Get user activity
+    response = client.get(
+        f"/api/v1/users/{regular_user.id}/activity",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "user_id" in data
+    assert "images_uploaded" in data
+    assert "last_login" in data
+    assert "api_key_usage" in data
+
+
+@pytest.mark.asyncio
+async def test_change_user_team(client: TestClient, admin_api_key: tuple, regular_user: UserModel):
+    """Test moving a user to a different team (admin only)"""
+    raw_key, _ = admin_api_key
+    
+    # Create another team
+    new_team = TeamModel(
+        name="New Team",
+        description="A new team for testing"
+    )
+    created_team = await team_repository.create(new_team)
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Move user to new team
+    response = client.put(
+        f"/api/v1/users/{regular_user.id}/team",
+        headers=headers,
+        json={
+            "team_id": str(created_team.id)
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["team_id"] == str(created_team.id)
+
+
+@pytest.mark.asyncio
+async def test_user_search(client: TestClient, admin_api_key: tuple):
+    """Test searching for users by email or name"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Search for users
+    response = client.get(
+        "/api/v1/users/search?query=admin",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "users" in data
+    assert "total" in data
+    
+    # Results should contain users matching the query
+    for user in data["users"]:
+        assert "admin" in user["email"].lower() or "admin" in user["name"].lower()
+
+
+@pytest.mark.asyncio
+async def test_user_pagination(client: TestClient, admin_api_key: tuple):
+    """Test user listing with pagination"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Test pagination
+    response = client.get(
+        "/api/v1/users?page=1&limit=10",
+        headers=headers
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert "users" in data
+    assert "pagination" in data
+    assert "total" in data["pagination"]
+    assert "page" in data["pagination"]
+    assert "pages" in data["pagination"]
+    assert len(data["users"]) <= 10
+
+
+@pytest.mark.asyncio
+async def test_invalid_user_id(client: TestClient, admin_api_key: tuple):
+    """Test handling of invalid user IDs"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to get user with invalid ID
+    response = client.get(
+        "/api/v1/users/invalid-id",
+        headers=headers
+    )
+    
+    # Check that the request returns 400 Bad Request
+    assert response.status_code == 400
+    assert "detail" in response.json()
+    assert "invalid" in response.json()["detail"].lower()
+
+
+@pytest.mark.asyncio
+async def test_nonexistent_user(client: TestClient, admin_api_key: tuple):
+    """Test handling of nonexistent user IDs"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to get nonexistent user
+    nonexistent_id = str(ObjectId())
+    response = client.get(
+        f"/api/v1/users/{nonexistent_id}",
+        headers=headers
+    )
+    
+    # Check that the request returns 404 Not Found
+    assert response.status_code == 404
+    assert "detail" in response.json()
+    assert "not found" in response.json()["detail"].lower()
+
+
+@pytest.mark.asyncio
+async def test_duplicate_email_validation(client: TestClient, admin_api_key: tuple, regular_user: UserModel):
+    """Test that duplicate emails are not allowed"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Try to create user with existing email
+    response = client.post(
+        "/api/v1/users",
+        headers=headers,
+        json={
+            "email": regular_user.email,  # Duplicate email
+            "name": "Duplicate Email User",
+            "team_id": str(regular_user.team_id),
+            "is_admin": False
+        }
+    )
+    
+    # Check that the request is rejected
+    assert response.status_code == 400
+    assert "detail" in response.json()
+    assert "email" in response.json()["detail"].lower()
+
+
+@pytest.mark.asyncio
+async def test_user_role_management(client: TestClient, admin_api_key: tuple, regular_user: UserModel):
+    """Test managing user roles and permissions"""
+    raw_key, _ = admin_api_key
+    
+    # Set up the headers
+    headers = {"X-API-Key": raw_key}
+    
+    # Promote user to admin
+    response = client.put(
+        f"/api/v1/users/{regular_user.id}/role",
+        headers=headers,
+        json={
+            "is_admin": True
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["is_admin"] is True
+    
+    # Demote user back to regular
+    response = client.put(
+        f"/api/v1/users/{regular_user.id}/role",
+        headers=headers,
+        json={
+            "is_admin": False
+        }
+    )
+    
+    # Check response
+    assert response.status_code == 200
+    data = response.json()
+    assert data["is_admin"] is False 
\ No newline at end of file
diff --git a/tests/auth/test_security.py b/tests/auth/test_security.py
new file mode 100644
index 0000000..4bf1925
--- /dev/null
+++ b/tests/auth/test_security.py
@@ -0,0 +1,268 @@
+import pytest
+import hashlib
+from datetime import datetime, timedelta
+from bson import ObjectId
+
+from src.auth.security import (
+    generate_api_key, 
+    hash_api_key, 
+    verify_api_key,
+    create_access_token,
+    verify_token
+)
+from src.models.api_key import ApiKeyModel
+from src.models.user import UserModel
+from src.models.team import TeamModel
+
+
+class TestApiKeySecurity:
+    """Test API key generation and validation security"""
+    
+    def test_generate_api_key(self):
+        """Test API key generation produces unique, secure keys"""
+        team_id = str(ObjectId())
+        user_id = str(ObjectId())
+        
+        # Generate multiple keys
+        key1, hash1 = generate_api_key(team_id, user_id)
+        key2, hash2 = generate_api_key(team_id, user_id)
+        
+        # Keys should be different
+        assert key1 != key2
+        assert hash1 != hash2
+        
+        # Keys should be sufficiently long
+        assert len(key1) >= 32
+        assert len(hash1) >= 32
+        
+        # Keys should contain team and user info
+        assert team_id in key1 or user_id in key1
+    
+    def test_hash_api_key_consistency(self):
+        """Test that hashing the same key produces the same hash"""
+        key = "test-api-key-123"
+        
+        hash1 = hash_api_key(key)
+        hash2 = hash_api_key(key)
+        
+        assert hash1 == hash2
+        assert len(hash1) >= 32  # Should be a proper hash length
+    
+    def test_verify_api_key_valid(self):
+        """Test verifying a valid API key"""
+        team_id = str(ObjectId())
+        user_id = str(ObjectId())
+        
+        raw_key, key_hash = generate_api_key(team_id, user_id)
+        
+        # Verification should succeed
+        assert verify_api_key(raw_key, key_hash) is True
+    
+    def test_verify_api_key_invalid(self):
+        """Test verifying an invalid API key"""
+        team_id = str(ObjectId())
+        user_id = str(ObjectId())
+        
+        raw_key, key_hash = generate_api_key(team_id, user_id)
+        
+        # Wrong key should fail
+        assert verify_api_key("wrong-key", key_hash) is False
+        
+        # Wrong hash should fail
+        assert verify_api_key(raw_key, "wrong-hash") is False
+    
+    def test_api_key_format(self):
+        """Test that generated API keys follow expected format"""
+        team_id = str(ObjectId())
+        user_id = str(ObjectId())
+        
+        raw_key, key_hash = generate_api_key(team_id, user_id)
+        
+        # Key should have expected structure (prefix.hash format)
+        assert "." in raw_key
+        parts = raw_key.split(".")
+        assert len(parts) == 2
+        
+        # First part should be readable prefix
+        prefix = parts[0]
+        assert len(prefix) >= 8
+        
+        # Second part should be hash-like
+        hash_part = parts[1]
+        assert len(hash_part) >= 32
+
+
+class TestTokenSecurity:
+    """Test JWT token generation and validation"""
+    
+    def test_create_access_token(self):
+        """Test creating access tokens"""
+        user_id = str(ObjectId())
+        team_id = str(ObjectId())
+        
+        token = create_access_token(
+            data={"user_id": user_id, "team_id": team_id}
+        )
+        
+        assert token is not None
+        assert isinstance(token, str)
+        assert len(token) > 50  # JWT tokens are typically long
+    
+    def test_verify_token_valid(self):
+        """Test verifying a valid token"""
+        user_id = str(ObjectId())
+        team_id = str(ObjectId())
+        
+        token = create_access_token(
+            data={"user_id": user_id, "team_id": team_id}
+        )
+        
+        payload = verify_token(token)
+        assert payload is not None
+        assert payload["user_id"] == user_id
+        assert payload["team_id"] == team_id
+    
+    def test_verify_token_invalid(self):
+        """Test verifying an invalid token"""
+        # Invalid token should return None
+        assert verify_token("invalid-token") is None
+        assert verify_token("") is None
+        assert verify_token(None) is None
+    
+    def test_token_expiration(self):
+        """Test token expiration handling"""
+        user_id = str(ObjectId())
+        
+        # Create token with very short expiration
+        token = create_access_token(
+            data={"user_id": user_id},
+            expires_delta=timedelta(seconds=-1)  # Already expired
+        )
+        
+        # Should fail verification due to expiration
+        payload = verify_token(token)
+        assert payload is None
+
+
+class TestSecurityValidation:
+    """Test security validation functions"""
+    
+    def test_validate_team_access(self):
+        """Test team access validation"""
+        team_id = ObjectId()
+        user_team_id = ObjectId()
+        
+        # User should have access to their own team
+        from src.auth.security import validate_team_access
+        assert validate_team_access(str(team_id), str(team_id)) is True
+        
+        # User should not have access to other teams
+        assert validate_team_access(str(user_team_id), str(team_id)) is False
+    
+    def test_validate_admin_permissions(self):
+        """Test admin permission validation"""
+        from src.auth.security import validate_admin_permissions
+        
+        admin_user = UserModel(
+            email="admin@test.com",
+            name="Admin User",
+            team_id=ObjectId(),
+            is_admin=True
+        )
+        
+        regular_user = UserModel(
+            email="user@test.com", 
+            name="Regular User",
+            team_id=ObjectId(),
+            is_admin=False
+        )
+        
+        assert validate_admin_permissions(admin_user) is True
+        assert validate_admin_permissions(regular_user) is False
+    
+    def test_rate_limiting_validation(self):
+        """Test rate limiting for API keys"""
+        # This would test rate limiting functionality
+        # Implementation depends on the actual rate limiting strategy
+        pass
+    
+    def test_api_key_expiration_check(self):
+        """Test API key expiration validation"""
+        team_id = ObjectId()
+        user_id = ObjectId()
+        
+        # Create expired API key
+        expired_key = ApiKeyModel(
+            key_hash="test-hash",
+            user_id=user_id,
+            team_id=team_id,
+            name="Expired Key",
+            expiry_date=datetime.utcnow() - timedelta(days=1),
+            is_active=True
+        )
+        
+        # Create valid API key
+        valid_key = ApiKeyModel(
+            key_hash="test-hash-2",
+            user_id=user_id,
+            team_id=team_id,
+            name="Valid Key",
+            expiry_date=datetime.utcnow() + timedelta(days=30),
+            is_active=True
+        )
+        
+        from src.auth.security import is_api_key_valid
+        
+        assert is_api_key_valid(expired_key) is False
+        assert is_api_key_valid(valid_key) is True
+    
+    def test_inactive_api_key_check(self):
+        """Test inactive API key validation"""
+        team_id = ObjectId()
+        user_id = ObjectId()
+        
+        # Create inactive API key
+        inactive_key = ApiKeyModel(
+            key_hash="test-hash",
+            user_id=user_id,
+            team_id=team_id,
+            name="Inactive Key",
+            expiry_date=datetime.utcnow() + timedelta(days=30),
+            is_active=False
+        )
+        
+        from src.auth.security import is_api_key_valid
+        assert is_api_key_valid(inactive_key) is False
+
+
+class TestSecurityHeaders:
+    """Test security headers and middleware"""
+    
+    def test_cors_headers(self):
+        """Test CORS header configuration"""
+        # This would test CORS configuration
+        pass
+    
+    def test_security_headers(self):
+        """Test security headers like X-Frame-Options, etc."""
+        # This would test security headers
+        pass
+    
+    def test_https_enforcement(self):
+        """Test HTTPS enforcement in production"""
+        # This would test HTTPS redirect functionality
+        pass
+
+
+class TestPasswordSecurity:
+    """Test password hashing and validation if implemented"""
+    
+    def test_password_hashing(self):
+        """Test password hashing functionality"""
+        # If password authentication is implemented
+        pass
+    
+    def test_password_validation(self):
+        """Test password strength validation"""
+        # If password authentication is implemented
+        pass 
\ No newline at end of file
diff --git a/tests/services/test_embedding_service.py b/tests/services/test_embedding_service.py
new file mode 100644
index 0000000..b102f74
--- /dev/null
+++ b/tests/services/test_embedding_service.py
@@ -0,0 +1,360 @@
+import pytest
+import numpy as np
+from unittest.mock import patch, MagicMock, AsyncMock
+from bson import ObjectId
+from io import BytesIO
+
+from src.services.embedding_service import EmbeddingService
+from src.models.image import ImageModel
+
+
+class TestEmbeddingService:
+    """Test embedding generation for images"""
+    
+    @pytest.fixture
+    def mock_vision_client(self):
+        """Mock Google Cloud Vision client"""
+        mock_client = MagicMock()
+        mock_response = MagicMock()
+        mock_response.image_properties_annotation.dominant_colors.colors = []
+        mock_response.label_annotations = []
+        mock_response.object_localizations = []
+        mock_response.text_annotations = []
+        mock_client.annotate_image.return_value = mock_response
+        return mock_client
+    
+    @pytest.fixture
+    def embedding_service(self, mock_vision_client):
+        """Create embedding service with mocked dependencies"""
+        with patch('src.services.embedding_service.vision') as mock_vision:
+            mock_vision.ImageAnnotatorClient.return_value = mock_vision_client
+            service = EmbeddingService()
+            service.client = mock_vision_client
+            return service
+    
+    @pytest.fixture
+    def sample_image_data(self):
+        """Create sample image data"""
+        # Create a simple test image (1x1 pixel PNG)
+        image_data = b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x01\x00\x00\x00\x01\x08\x02\x00\x00\x00\x90wS\xde\x00\x00\x00\tpHYs\x00\x00\x0b\x13\x00\x00\x0b\x13\x01\x00\x9a\x9c\x18\x00\x00\x00\nIDATx\x9cc```\x00\x00\x00\x04\x00\x01\xdd\x8d\xb4\x1c\x00\x00\x00\x00IEND\xaeB`\x82'
+        return BytesIO(image_data)
+    
+    @pytest.fixture
+    def sample_image_model(self):
+        """Create a sample image model"""
+        return ImageModel(
+            filename="test-image.jpg",
+            original_filename="test_image.jpg",
+            file_size=1024,
+            content_type="image/jpeg",
+            storage_path="images/test-image.jpg",
+            team_id=ObjectId(),
+            uploader_id=ObjectId()
+        )
+    
+    def test_generate_embedding_from_image(self, embedding_service, sample_image_data):
+        """Test generating embeddings from image data"""
+        # Mock the embedding generation
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            # Generate embedding
+            embedding = embedding_service.generate_embedding(sample_image_data)
+            
+            # Verify embedding was generated
+            assert embedding is not None
+            assert len(embedding) == 512
+            assert isinstance(embedding, list)
+            assert all(isinstance(x, (int, float)) for x in embedding)
+    
+    def test_extract_image_features(self, embedding_service, sample_image_data):
+        """Test extracting features from images using Vision API"""
+        # Mock Vision API response
+        mock_response = MagicMock()
+        mock_response.label_annotations = [
+            MagicMock(description="cat", score=0.95),
+            MagicMock(description="animal", score=0.87),
+            MagicMock(description="pet", score=0.82)
+        ]
+        mock_response.object_localizations = [
+            MagicMock(name="Cat", score=0.9)
+        ]
+        mock_response.image_properties_annotation.dominant_colors.colors = [
+            MagicMock(color=MagicMock(red=255, green=100, blue=50), score=0.8)
+        ]
+        
+        embedding_service.client.annotate_image.return_value = mock_response
+        
+        # Extract features
+        features = embedding_service.extract_image_features(sample_image_data)
+        
+        # Verify features were extracted
+        assert 'labels' in features
+        assert 'objects' in features
+        assert 'colors' in features
+        assert len(features['labels']) == 3
+        assert features['labels'][0]['description'] == "cat"
+        assert features['labels'][0]['score'] == 0.95
+    
+    def test_generate_embedding_with_metadata(self, embedding_service, sample_image_data, sample_image_model):
+        """Test generating embeddings with image metadata"""
+        mock_embedding = np.random.rand(512).tolist()
+        mock_features = {
+            'labels': [{'description': 'cat', 'score': 0.95}],
+            'objects': [{'name': 'Cat', 'score': 0.9}],
+            'colors': [{'red': 255, 'green': 100, 'blue': 50, 'score': 0.8}]
+        }
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract_features, \
+             patch.object(embedding_service, 'extract_image_features') as mock_extract_metadata:
+            
+            mock_extract_features.return_value = mock_embedding
+            mock_extract_metadata.return_value = mock_features
+            
+            # Generate embedding with metadata
+            result = embedding_service.generate_embedding_with_metadata(
+                sample_image_data, sample_image_model
+            )
+            
+            # Verify result structure
+            assert 'embedding' in result
+            assert 'metadata' in result
+            assert 'model' in result
+            assert len(result['embedding']) == 512
+            assert result['metadata']['labels'][0]['description'] == 'cat'
+            assert result['model'] == 'clip'  # or whatever model is used
+    
+    def test_batch_generate_embeddings(self, embedding_service):
+        """Test generating embeddings for multiple images in batch"""
+        # Create multiple image data samples
+        image_batch = []
+        for i in range(3):
+            image_data = BytesIO(b'fake_image_data_' + str(i).encode())
+            image_model = ImageModel(
+                filename=f"image{i}.jpg",
+                original_filename=f"image{i}.jpg",
+                file_size=1024,
+                content_type="image/jpeg",
+                storage_path=f"images/image{i}.jpg",
+                team_id=ObjectId(),
+                uploader_id=ObjectId()
+            )
+            image_batch.append((image_data, image_model))
+        
+        # Mock embedding generation
+        mock_embedding = np.random.rand(512).tolist()
+        with patch.object(embedding_service, 'generate_embedding_with_metadata') as mock_generate:
+            mock_generate.return_value = {
+                'embedding': mock_embedding,
+                'metadata': {'labels': []},
+                'model': 'clip'
+            }
+            
+            # Generate batch embeddings
+            results = embedding_service.batch_generate_embeddings(image_batch)
+            
+            # Verify batch results
+            assert len(results) == 3
+            assert all('embedding' in result for result in results)
+            assert all('metadata' in result for result in results)
+    
+    def test_embedding_model_consistency(self, embedding_service, sample_image_data):
+        """Test that the same image produces consistent embeddings"""
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            # Generate embedding twice
+            embedding1 = embedding_service.generate_embedding(sample_image_data)
+            sample_image_data.seek(0)  # Reset stream position
+            embedding2 = embedding_service.generate_embedding(sample_image_data)
+            
+            # Embeddings should be identical for the same image
+            assert embedding1 == embedding2
+    
+    def test_embedding_dimension_validation(self, embedding_service):
+        """Test that embeddings have the correct dimensions"""
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            # Validate embedding dimensions
+            assert embedding_service.validate_embedding_dimensions(mock_embedding) is True
+            
+            # Test wrong dimensions
+            wrong_embedding = np.random.rand(256).tolist()
+            assert embedding_service.validate_embedding_dimensions(wrong_embedding) is False
+    
+    def test_handle_unsupported_image_format(self, embedding_service):
+        """Test handling of unsupported image formats"""
+        # Create invalid image data
+        invalid_data = BytesIO(b'not_an_image')
+        
+        # Should raise appropriate exception
+        with pytest.raises(ValueError):
+            embedding_service.generate_embedding(invalid_data)
+    
+    def test_handle_corrupted_image(self, embedding_service):
+        """Test handling of corrupted image data"""
+        # Create corrupted image data
+        corrupted_data = BytesIO(b'\x89PNG\r\n\x1a\n\x00\x00corrupted')
+        
+        # Should handle gracefully
+        with pytest.raises(Exception):
+            embedding_service.generate_embedding(corrupted_data)
+    
+    def test_vision_api_error_handling(self, embedding_service, sample_image_data):
+        """Test handling of Vision API errors"""
+        # Mock Vision API error
+        embedding_service.client.annotate_image.side_effect = Exception("Vision API error")
+        
+        # Should handle the error gracefully
+        with pytest.raises(Exception):
+            embedding_service.extract_image_features(sample_image_data)
+    
+    def test_embedding_caching(self, embedding_service, sample_image_data):
+        """Test caching of embeddings for the same image"""
+        # This would test caching functionality if implemented
+        pass
+    
+    def test_embedding_quality_metrics(self, embedding_service, sample_image_data):
+        """Test quality metrics for generated embeddings"""
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            # Generate embedding
+            embedding = embedding_service.generate_embedding(sample_image_data)
+            
+            # Check embedding quality metrics
+            quality_score = embedding_service.calculate_embedding_quality(embedding)
+            assert 0 <= quality_score <= 1
+    
+    def test_different_image_types(self, embedding_service):
+        """Test embedding generation for different image types"""
+        image_types = [
+            ('image/jpeg', b'fake_jpeg_data'),
+            ('image/png', b'fake_png_data'),
+            ('image/webp', b'fake_webp_data')
+        ]
+        
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            for content_type, data in image_types:
+                image_data = BytesIO(data)
+                
+                # Should handle different image types
+                embedding = embedding_service.generate_embedding(image_data)
+                assert len(embedding) == 512
+    
+    def test_large_image_handling(self, embedding_service):
+        """Test handling of large images"""
+        # Create large image data (simulated)
+        large_image_data = BytesIO(b'x' * (10 * 1024 * 1024))  # 10MB
+        
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = mock_embedding
+            
+            # Should handle large images
+            embedding = embedding_service.generate_embedding(large_image_data)
+            assert len(embedding) == 512
+    
+    def test_embedding_normalization(self, embedding_service, sample_image_data):
+        """Test that embeddings are properly normalized"""
+        # Generate raw embedding
+        raw_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            mock_extract.return_value = raw_embedding
+            
+            # Generate normalized embedding
+            embedding = embedding_service.generate_embedding(sample_image_data, normalize=True)
+            
+            # Check if embedding is normalized (L2 norm should be 1)
+            norm = np.linalg.norm(embedding)
+            assert abs(norm - 1.0) < 0.001  # Allow small floating point errors
+
+
+class TestEmbeddingServiceIntegration:
+    """Integration tests for embedding service with other components"""
+    
+    def test_embedding_to_vector_store_integration(self, embedding_service, sample_image_data, sample_image_model):
+        """Test integration with vector store service"""
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, 'generate_embedding_with_metadata') as mock_generate, \
+             patch('src.services.vector_store.VectorStoreService') as mock_vector_store:
+            
+            mock_generate.return_value = {
+                'embedding': mock_embedding,
+                'metadata': {'labels': [{'description': 'cat', 'score': 0.95}]},
+                'model': 'clip'
+            }
+            
+            mock_store = mock_vector_store.return_value
+            mock_store.store_embedding.return_value = 'embedding_id_123'
+            
+            # Process image and store embedding
+            result = embedding_service.process_and_store_image(
+                sample_image_data, sample_image_model
+            )
+            
+            # Verify integration
+            assert result['embedding_id'] == 'embedding_id_123'
+            mock_store.store_embedding.assert_called_once()
+    
+    def test_pubsub_trigger_integration(self, embedding_service):
+        """Test integration with Pub/Sub message processing"""
+        # Mock Pub/Sub message
+        mock_message = {
+            'image_id': str(ObjectId()),
+            'storage_path': 'images/test.jpg',
+            'team_id': str(ObjectId())
+        }
+        
+        with patch.object(embedding_service, 'process_image_from_storage') as mock_process:
+            mock_process.return_value = {'embedding_id': 'emb123'}
+            
+            # Process Pub/Sub message
+            result = embedding_service.handle_pubsub_message(mock_message)
+            
+            # Verify message processing
+            assert result['embedding_id'] == 'emb123'
+            mock_process.assert_called_once_with(
+                mock_message['storage_path'],
+                mock_message['image_id'],
+                mock_message['team_id']
+            )
+    
+    def test_cloud_function_deployment(self, embedding_service):
+        """Test Cloud Function deployment compatibility"""
+        # Test that the service can be initialized in a Cloud Function environment
+        # This would test environment variable loading, authentication, etc.
+        pass
+    
+    def test_error_recovery_and_retry(self, embedding_service, sample_image_data):
+        """Test error recovery and retry mechanisms"""
+        # Mock transient error followed by success
+        mock_embedding = np.random.rand(512).tolist()
+        
+        with patch.object(embedding_service, '_extract_features') as mock_extract:
+            # First call fails, second succeeds
+            mock_extract.side_effect = [Exception("Transient error"), mock_embedding]
+            
+            # Should retry and succeed
+            embedding = embedding_service.generate_embedding_with_retry(
+                sample_image_data, max_retries=2
+            )
+            
+            assert len(embedding) == 512
+            assert mock_extract.call_count == 2 
\ No newline at end of file
diff --git a/tests/services/test_image_processor.py b/tests/services/test_image_processor.py
new file mode 100644
index 0000000..de822d8
--- /dev/null
+++ b/tests/services/test_image_processor.py
@@ -0,0 +1,489 @@
+import pytest
+import numpy as np
+from unittest.mock import patch, MagicMock
+from bson import ObjectId
+from io import BytesIO
+from PIL import Image
+
+from src.services.image_processor import ImageProcessor
+from src.models.image import ImageModel
+
+
+class TestImageProcessor:
+    """Test image processing functionality"""
+    
+    @pytest.fixture
+    def image_processor(self):
+        """Create image processor instance"""
+        return ImageProcessor()
+    
+    @pytest.fixture
+    def sample_image_data(self):
+        """Create sample image data"""
+        # Create a simple test image using PIL
+        img = Image.new('RGB', (800, 600), color='red')
+        img_bytes = BytesIO()
+        img.save(img_bytes, format='JPEG')
+        img_bytes.seek(0)
+        return img_bytes
+    
+    @pytest.fixture
+    def sample_png_image(self):
+        """Create sample PNG image data"""
+        img = Image.new('RGBA', (400, 300), color=(255, 0, 0, 128))
+        img_bytes = BytesIO()
+        img.save(img_bytes, format='PNG')
+        img_bytes.seek(0)
+        return img_bytes
+    
+    @pytest.fixture
+    def sample_image_model(self):
+        """Create a sample image model"""
+        return ImageModel(
+            filename="test-image.jpg",
+            original_filename="test_image.jpg",
+            file_size=1024,
+            content_type="image/jpeg",
+            storage_path="images/test-image.jpg",
+            team_id=ObjectId(),
+            uploader_id=ObjectId()
+        )
+    
+    def test_extract_image_metadata(self, image_processor, sample_image_data):
+        """Test extracting basic image metadata"""
+        # Extract metadata
+        metadata = image_processor.extract_metadata(sample_image_data)
+        
+        # Verify metadata extraction
+        assert 'width' in metadata
+        assert 'height' in metadata
+        assert 'format' in metadata
+        assert 'mode' in metadata
+        assert metadata['width'] == 800
+        assert metadata['height'] == 600
+        assert metadata['format'] == 'JPEG'
+    
+    def test_extract_exif_data(self, image_processor):
+        """Test extracting EXIF data from images"""
+        # Create image with EXIF data (simulated)
+        img = Image.new('RGB', (100, 100), color='blue')
+        img_bytes = BytesIO()
+        img.save(img_bytes, format='JPEG')
+        img_bytes.seek(0)
+        
+        # Extract EXIF data
+        exif_data = image_processor.extract_exif_data(img_bytes)
+        
+        # Verify EXIF extraction (may be empty for generated images)
+        assert isinstance(exif_data, dict)
+    
+    def test_resize_image(self, image_processor, sample_image_data):
+        """Test resizing images while maintaining aspect ratio"""
+        # Resize image
+        resized_data = image_processor.resize_image(
+            sample_image_data, 
+            max_width=400, 
+            max_height=300
+        )
+        
+        # Verify resized image
+        assert resized_data is not None
+        
+        # Check new dimensions
+        resized_img = Image.open(resized_data)
+        assert resized_img.width <= 400
+        assert resized_img.height <= 300
+        
+        # Aspect ratio should be maintained
+        original_ratio = 800 / 600
+        new_ratio = resized_img.width / resized_img.height
+        assert abs(original_ratio - new_ratio) < 0.01
+    
+    def test_generate_thumbnail(self, image_processor, sample_image_data):
+        """Test generating image thumbnails"""
+        # Generate thumbnail
+        thumbnail_data = image_processor.generate_thumbnail(
+            sample_image_data,
+            size=(150, 150)
+        )
+        
+        # Verify thumbnail
+        assert thumbnail_data is not None
+        
+        # Check thumbnail dimensions
+        thumbnail_img = Image.open(thumbnail_data)
+        assert thumbnail_img.width <= 150
+        assert thumbnail_img.height <= 150
+    
+    def test_optimize_image_quality(self, image_processor, sample_image_data):
+        """Test optimizing image quality and file size"""
+        # Get original size
+        original_size = len(sample_image_data.getvalue())
+        
+        # Optimize image
+        optimized_data = image_processor.optimize_image(
+            sample_image_data,
+            quality=85,
+            optimize=True
+        )
+        
+        # Verify optimization
+        assert optimized_data is not None
+        optimized_size = len(optimized_data.getvalue())
+        
+        # Optimized image should typically be smaller or similar size
+        assert optimized_size <= original_size * 1.1  # Allow 10% tolerance
+    
+    def test_convert_image_format(self, image_processor, sample_png_image):
+        """Test converting between image formats"""
+        # Convert PNG to JPEG
+        jpeg_data = image_processor.convert_format(
+            sample_png_image,
+            target_format='JPEG'
+        )
+        
+        # Verify conversion
+        assert jpeg_data is not None
+        
+        # Check converted image
+        converted_img = Image.open(jpeg_data)
+        assert converted_img.format == 'JPEG'
+    
+    def test_detect_image_colors(self, image_processor, sample_image_data):
+        """Test detecting dominant colors in images"""
+        # Detect colors
+        colors = image_processor.detect_dominant_colors(
+            sample_image_data,
+            num_colors=5
+        )
+        
+        # Verify color detection
+        assert isinstance(colors, list)
+        assert len(colors) <= 5
+        
+        # Each color should have RGB values and percentage
+        for color in colors:
+            assert 'rgb' in color
+            assert 'percentage' in color
+            assert len(color['rgb']) == 3
+            assert 0 <= color['percentage'] <= 100
+    
+    def test_validate_image_format(self, image_processor, sample_image_data):
+        """Test validating supported image formats"""
+        # Valid image should pass validation
+        is_valid = image_processor.validate_image_format(sample_image_data)
+        assert is_valid is True
+        
+        # Invalid data should fail validation
+        invalid_data = BytesIO(b'not_an_image')
+        is_valid = image_processor.validate_image_format(invalid_data)
+        assert is_valid is False
+    
+    def test_calculate_image_hash(self, image_processor, sample_image_data):
+        """Test calculating perceptual hash for duplicate detection"""
+        # Calculate hash
+        image_hash = image_processor.calculate_perceptual_hash(sample_image_data)
+        
+        # Verify hash
+        assert image_hash is not None
+        assert isinstance(image_hash, str)
+        assert len(image_hash) > 0
+        
+        # Same image should produce same hash
+        sample_image_data.seek(0)
+        hash2 = image_processor.calculate_perceptual_hash(sample_image_data)
+        assert image_hash == hash2
+    
+    def test_detect_image_orientation(self, image_processor, sample_image_data):
+        """Test detecting and correcting image orientation"""
+        # Detect orientation
+        orientation = image_processor.detect_orientation(sample_image_data)
+        
+        # Verify orientation detection
+        assert orientation in [0, 90, 180, 270]
+        
+        # Auto-correct orientation if needed
+        corrected_data = image_processor.auto_correct_orientation(sample_image_data)
+        assert corrected_data is not None
+    
+    def test_extract_text_from_image(self, image_processor):
+        """Test OCR text extraction from images"""
+        # Create image with text (simulated)
+        img = Image.new('RGB', (200, 100), color='white')
+        img_bytes = BytesIO()
+        img.save(img_bytes, format='JPEG')
+        img_bytes.seek(0)
+        
+        with patch('src.services.image_processor.pytesseract') as mock_ocr:
+            mock_ocr.image_to_string.return_value = "Sample text"
+            
+            # Extract text
+            text = image_processor.extract_text(img_bytes)
+            
+            # Verify text extraction
+            assert text == "Sample text"
+            mock_ocr.image_to_string.assert_called_once()
+    
+    def test_batch_process_images(self, image_processor):
+        """Test batch processing multiple images"""
+        # Create batch of images
+        image_batch = []
+        for i in range(3):
+            img = Image.new('RGB', (100, 100), color=(i*80, 0, 0))
+            img_bytes = BytesIO()
+            img.save(img_bytes, format='JPEG')
+            img_bytes.seek(0)
+            image_batch.append(img_bytes)
+        
+        # Process batch
+        results = image_processor.batch_process(
+            image_batch,
+            operations=['resize', 'thumbnail', 'metadata']
+        )
+        
+        # Verify batch processing
+        assert len(results) == 3
+        for result in results:
+            assert 'metadata' in result
+            assert 'resized' in result
+            assert 'thumbnail' in result
+    
+    def test_image_quality_assessment(self, image_processor, sample_image_data):
+        """Test assessing image quality metrics"""
+        # Assess quality
+        quality_metrics = image_processor.assess_quality(sample_image_data)
+        
+        # Verify quality metrics
+        assert 'sharpness' in quality_metrics
+        assert 'brightness' in quality_metrics
+        assert 'contrast' in quality_metrics
+        assert 'overall_score' in quality_metrics
+        
+        # Scores should be in valid ranges
+        assert 0 <= quality_metrics['overall_score'] <= 100
+    
+    def test_watermark_addition(self, image_processor, sample_image_data):
+        """Test adding watermarks to images"""
+        # Add text watermark
+        watermarked_data = image_processor.add_watermark(
+            sample_image_data,
+            watermark_text="SEREACT",
+            position="bottom-right",
+            opacity=0.5
+        )
+        
+        # Verify watermark addition
+        assert watermarked_data is not None
+        
+        # Check that image is still valid
+        watermarked_img = Image.open(watermarked_data)
+        assert watermarked_img.format == 'JPEG'
+    
+    def test_image_compression_levels(self, image_processor, sample_image_data):
+        """Test different compression levels"""
+        original_size = len(sample_image_data.getvalue())
+        
+        # Test different quality levels
+        for quality in [95, 85, 75, 60]:
+            compressed_data = image_processor.compress_image(
+                sample_image_data,
+                quality=quality
+            )
+            
+            compressed_size = len(compressed_data.getvalue())
+            
+            # Lower quality should generally result in smaller files
+            if quality < 95:
+                assert compressed_size <= original_size
+            
+            # Reset stream position
+            sample_image_data.seek(0)
+    
+    def test_handle_corrupted_image(self, image_processor):
+        """Test handling of corrupted image data"""
+        # Create corrupted image data
+        corrupted_data = BytesIO(b'\x89PNG\r\n\x1a\n\x00\x00corrupted')
+        
+        # Should handle gracefully
+        with pytest.raises(Exception):
+            image_processor.extract_metadata(corrupted_data)
+    
+    def test_large_image_processing(self, image_processor):
+        """Test processing very large images"""
+        # Create large image (simulated)
+        large_img = Image.new('RGB', (4000, 3000), color='green')
+        img_bytes = BytesIO()
+        large_img.save(img_bytes, format='JPEG', quality=95)
+        img_bytes.seek(0)
+        
+        # Process large image
+        metadata = image_processor.extract_metadata(img_bytes)
+        
+        # Verify processing
+        assert metadata['width'] == 4000
+        assert metadata['height'] == 3000
+        
+        # Test resizing large image
+        img_bytes.seek(0)
+        resized_data = image_processor.resize_image(
+            img_bytes,
+            max_width=1920,
+            max_height=1080
+        )
+        
+        resized_img = Image.open(resized_data)
+        assert resized_img.width <= 1920
+        assert resized_img.height <= 1080
+    
+    def test_progressive_jpeg_support(self, image_processor, sample_image_data):
+        """Test support for progressive JPEG format"""
+        # Convert to progressive JPEG
+        progressive_data = image_processor.convert_to_progressive_jpeg(
+            sample_image_data
+        )
+        
+        # Verify progressive format
+        assert progressive_data is not None
+        
+        # Check that it's still a valid JPEG
+        progressive_img = Image.open(progressive_data)
+        assert progressive_img.format == 'JPEG'
+
+
+class TestImageProcessorIntegration:
+    """Integration tests for image processor with other services"""
+    
+    def test_integration_with_storage_service(self, image_processor, sample_image_data):
+        """Test integration with storage service"""
+        with patch('src.services.storage.StorageService') as mock_storage:
+            mock_storage_instance = mock_storage.return_value
+            mock_storage_instance.upload_file.return_value = (
+                'images/processed.jpg', 'image/jpeg', 1024, {}
+            )
+            
+            # Process and upload image
+            result = image_processor.process_and_upload(
+                sample_image_data,
+                operations=['resize', 'optimize'],
+                team_id=str(ObjectId())
+            )
+            
+            # Verify integration
+            assert 'storage_path' in result
+            mock_storage_instance.upload_file.assert_called_once()
+    
+    def test_integration_with_embedding_service(self, image_processor, sample_image_data):
+        """Test integration with embedding service"""
+        with patch('src.services.embedding_service.EmbeddingService') as mock_embedding:
+            mock_embedding_instance = mock_embedding.return_value
+            mock_embedding_instance.generate_embedding.return_value = [0.1] * 512
+            
+            # Process image and generate embedding
+            result = image_processor.process_for_embedding(sample_image_data)
+            
+            # Verify integration
+            assert 'processed_image' in result
+            assert 'embedding' in result
+            mock_embedding_instance.generate_embedding.assert_called_once()
+    
+    def test_pubsub_message_processing(self, image_processor):
+        """Test processing images from Pub/Sub messages"""
+        # Mock Pub/Sub message
+        message_data = {
+            'image_id': str(ObjectId()),
+            'storage_path': 'images/raw/test.jpg',
+            'operations': ['resize', 'thumbnail', 'optimize']
+        }
+        
+        with patch.object(image_processor, 'process_from_storage') as mock_process:
+            mock_process.return_value = {
+                'processed_path': 'images/processed/test.jpg',
+                'thumbnail_path': 'images/thumbnails/test.jpg'
+            }
+            
+            # Process message
+            result = image_processor.handle_processing_message(message_data)
+            
+            # Verify message processing
+            assert 'processed_path' in result
+            mock_process.assert_called_once()
+    
+    def test_error_handling_and_retry(self, image_processor, sample_image_data):
+        """Test error handling and retry mechanisms"""
+        # Mock transient error followed by success
+        with patch.object(image_processor, 'extract_metadata') as mock_extract:
+            # First call fails, second succeeds
+            mock_extract.side_effect = [
+                Exception("Transient error"),
+                {'width': 800, 'height': 600, 'format': 'JPEG'}
+            ]
+            
+            # Should retry and succeed
+            metadata = image_processor.extract_metadata_with_retry(
+                sample_image_data,
+                max_retries=2
+            )
+            
+            assert metadata['width'] == 800
+            assert mock_extract.call_count == 2
+
+
+class TestImageProcessorPerformance:
+    """Performance tests for image processing"""
+    
+    def test_processing_speed_benchmarks(self, image_processor):
+        """Test processing speed for different image sizes"""
+        import time
+        
+        sizes = [(100, 100), (500, 500), (1000, 1000)]
+        
+        for width, height in sizes:
+            # Create test image
+            img = Image.new('RGB', (width, height), color='blue')
+            img_bytes = BytesIO()
+            img.save(img_bytes, format='JPEG')
+            img_bytes.seek(0)
+            
+            # Measure processing time
+            start_time = time.time()
+            metadata = image_processor.extract_metadata(img_bytes)
+            processing_time = time.time() - start_time
+            
+            # Verify reasonable processing time (adjust thresholds as needed)
+            assert processing_time < 5.0  # Should process within 5 seconds
+            assert metadata['width'] == width
+            assert metadata['height'] == height
+    
+    def test_memory_usage_optimization(self, image_processor):
+        """Test memory usage during image processing"""
+        # This would test memory usage patterns
+        # Implementation depends on memory profiling tools
+        pass
+    
+    def test_concurrent_processing(self, image_processor):
+        """Test concurrent image processing"""
+        import concurrent.futures
+        
+        # Create multiple test images
+        images = []
+        for i in range(5):
+            img = Image.new('RGB', (200, 200), color=(i*50, 0, 0))
+            img_bytes = BytesIO()
+            img.save(img_bytes, format='JPEG')
+            img_bytes.seek(0)
+            images.append(img_bytes)
+        
+        # Process concurrently
+        with concurrent.futures.ThreadPoolExecutor(max_workers=3) as executor:
+            futures = [
+                executor.submit(image_processor.extract_metadata, img)
+                for img in images
+            ]
+            
+            results = [future.result() for future in futures]
+        
+        # Verify all processed successfully
+        assert len(results) == 5
+        for result in results:
+            assert 'width' in result
+            assert 'height' in result 
\ No newline at end of file
diff --git a/tests/services/test_vector_store.py b/tests/services/test_vector_store.py
new file mode 100644
index 0000000..881cd03
--- /dev/null
+++ b/tests/services/test_vector_store.py
@@ -0,0 +1,391 @@
+import pytest
+import numpy as np
+from unittest.mock import patch, MagicMock, AsyncMock
+from bson import ObjectId
+
+from src.services.vector_store import VectorStoreService
+from src.models.image import ImageModel
+
+
+class TestVectorStoreService:
+    """Test vector store operations for semantic search"""
+    
+    @pytest.fixture
+    def mock_pinecone_index(self):
+        """Mock Pinecone index for testing"""
+        mock_index = MagicMock()
+        mock_index.upsert = MagicMock()
+        mock_index.query = MagicMock()
+        mock_index.delete = MagicMock()
+        mock_index.describe_index_stats = MagicMock()
+        return mock_index
+    
+    @pytest.fixture
+    def vector_store_service(self, mock_pinecone_index):
+        """Create vector store service with mocked dependencies"""
+        with patch('src.services.vector_store.pinecone') as mock_pinecone:
+            mock_pinecone.Index.return_value = mock_pinecone_index
+            service = VectorStoreService()
+            service.index = mock_pinecone_index
+            return service
+    
+    @pytest.fixture
+    def sample_embedding(self):
+        """Generate a sample embedding vector"""
+        return np.random.rand(512).tolist()  # 512-dimensional vector
+    
+    @pytest.fixture
+    def sample_image(self):
+        """Create a sample image model"""
+        return ImageModel(
+            filename="test-image.jpg",
+            original_filename="test_image.jpg",
+            file_size=1024,
+            content_type="image/jpeg",
+            storage_path="images/test-image.jpg",
+            team_id=ObjectId(),
+            uploader_id=ObjectId(),
+            description="A test image",
+            tags=["test", "image"]
+        )
+    
+    def test_store_embedding(self, vector_store_service, sample_embedding, sample_image):
+        """Test storing an embedding in the vector database"""
+        # Store the embedding
+        embedding_id = vector_store_service.store_embedding(
+            image_id=str(sample_image.id),
+            embedding=sample_embedding,
+            metadata={
+                "filename": sample_image.filename,
+                "team_id": str(sample_image.team_id),
+                "tags": sample_image.tags,
+                "description": sample_image.description
+            }
+        )
+        
+        # Verify the embedding was stored
+        assert embedding_id is not None
+        vector_store_service.index.upsert.assert_called_once()
+        
+        # Check the upsert call arguments
+        call_args = vector_store_service.index.upsert.call_args
+        vectors = call_args[1]['vectors']
+        assert len(vectors) == 1
+        assert vectors[0]['id'] == embedding_id
+        assert len(vectors[0]['values']) == len(sample_embedding)
+        assert 'metadata' in vectors[0]
+    
+    def test_search_similar_images(self, vector_store_service, sample_embedding):
+        """Test searching for similar images using vector similarity"""
+        # Mock search results
+        mock_results = {
+            'matches': [
+                {
+                    'id': 'embedding1',
+                    'score': 0.95,
+                    'metadata': {
+                        'image_id': str(ObjectId()),
+                        'filename': 'similar1.jpg',
+                        'team_id': str(ObjectId()),
+                        'tags': ['cat', 'animal']
+                    }
+                },
+                {
+                    'id': 'embedding2', 
+                    'score': 0.87,
+                    'metadata': {
+                        'image_id': str(ObjectId()),
+                        'filename': 'similar2.jpg',
+                        'team_id': str(ObjectId()),
+                        'tags': ['dog', 'animal']
+                    }
+                }
+            ]
+        }
+        vector_store_service.index.query.return_value = mock_results
+        
+        # Perform search
+        results = vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=str(ObjectId()),
+            top_k=10,
+            score_threshold=0.8
+        )
+        
+        # Verify search was performed
+        vector_store_service.index.query.assert_called_once()
+        
+        # Check results
+        assert len(results) == 2
+        assert results[0]['score'] == 0.95
+        assert results[1]['score'] == 0.87
+        assert all('image_id' in result for result in results)
+    
+    def test_search_with_filters(self, vector_store_service, sample_embedding):
+        """Test searching with metadata filters"""
+        team_id = str(ObjectId())
+        
+        # Perform search with team filter
+        vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=team_id,
+            top_k=5,
+            filters={"tags": {"$in": ["cat", "dog"]}}
+        )
+        
+        # Verify filter was applied
+        call_args = vector_store_service.index.query.call_args
+        assert 'filter' in call_args[1]
+        assert call_args[1]['filter']['team_id'] == team_id
+    
+    def test_delete_embedding(self, vector_store_service):
+        """Test deleting an embedding from the vector database"""
+        embedding_id = "test-embedding-123"
+        
+        # Delete the embedding
+        success = vector_store_service.delete_embedding(embedding_id)
+        
+        # Verify deletion was attempted
+        vector_store_service.index.delete.assert_called_once_with(ids=[embedding_id])
+        assert success is True
+    
+    def test_batch_store_embeddings(self, vector_store_service, sample_embedding):
+        """Test storing multiple embeddings in batch"""
+        # Create batch data
+        batch_data = []
+        for i in range(5):
+            batch_data.append({
+                'image_id': str(ObjectId()),
+                'embedding': sample_embedding,
+                'metadata': {
+                    'filename': f'image{i}.jpg',
+                    'team_id': str(ObjectId()),
+                    'tags': [f'tag{i}']
+                }
+            })
+        
+        # Store batch
+        embedding_ids = vector_store_service.batch_store_embeddings(batch_data)
+        
+        # Verify batch storage
+        assert len(embedding_ids) == 5
+        vector_store_service.index.upsert.assert_called_once()
+        
+        # Check batch upsert call
+        call_args = vector_store_service.index.upsert.call_args
+        vectors = call_args[1]['vectors']
+        assert len(vectors) == 5
+    
+    def test_get_index_stats(self, vector_store_service):
+        """Test getting vector database statistics"""
+        # Mock stats response
+        mock_stats = {
+            'total_vector_count': 1000,
+            'dimension': 512,
+            'index_fullness': 0.1
+        }
+        vector_store_service.index.describe_index_stats.return_value = mock_stats
+        
+        # Get stats
+        stats = vector_store_service.get_index_stats()
+        
+        # Verify stats retrieval
+        vector_store_service.index.describe_index_stats.assert_called_once()
+        assert stats['total_vector_count'] == 1000
+        assert stats['dimension'] == 512
+    
+    def test_search_with_score_threshold(self, vector_store_service, sample_embedding):
+        """Test filtering search results by score threshold"""
+        # Mock results with varying scores
+        mock_results = {
+            'matches': [
+                {'id': 'emb1', 'score': 0.95, 'metadata': {'image_id': '1'}},
+                {'id': 'emb2', 'score': 0.75, 'metadata': {'image_id': '2'}},
+                {'id': 'emb3', 'score': 0.65, 'metadata': {'image_id': '3'}},
+                {'id': 'emb4', 'score': 0.45, 'metadata': {'image_id': '4'}}
+            ]
+        }
+        vector_store_service.index.query.return_value = mock_results
+        
+        # Search with score threshold
+        results = vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=str(ObjectId()),
+            top_k=10,
+            score_threshold=0.7
+        )
+        
+        # Only results above threshold should be returned
+        assert len(results) == 2
+        assert all(result['score'] >= 0.7 for result in results)
+    
+    def test_update_embedding_metadata(self, vector_store_service):
+        """Test updating metadata for an existing embedding"""
+        embedding_id = "test-embedding-123"
+        new_metadata = {
+            'tags': ['updated', 'tag'],
+            'description': 'Updated description'
+        }
+        
+        # Update metadata
+        success = vector_store_service.update_embedding_metadata(
+            embedding_id, new_metadata
+        )
+        
+        # Verify update was attempted
+        # This would depend on the actual implementation
+        assert success is True
+    
+    def test_search_by_image_id(self, vector_store_service):
+        """Test searching for a specific image's embedding"""
+        image_id = str(ObjectId())
+        
+        # Mock search by metadata
+        mock_results = {
+            'matches': [
+                {
+                    'id': 'embedding1',
+                    'score': 1.0,
+                    'metadata': {
+                        'image_id': image_id,
+                        'filename': 'target.jpg'
+                    }
+                }
+            ]
+        }
+        vector_store_service.index.query.return_value = mock_results
+        
+        # Search by image ID
+        result = vector_store_service.get_embedding_by_image_id(image_id)
+        
+        # Verify result
+        assert result is not None
+        assert result['metadata']['image_id'] == image_id
+    
+    def test_bulk_delete_embeddings(self, vector_store_service):
+        """Test deleting multiple embeddings"""
+        embedding_ids = ['emb1', 'emb2', 'emb3']
+        
+        # Delete multiple embeddings
+        success = vector_store_service.bulk_delete_embeddings(embedding_ids)
+        
+        # Verify bulk deletion
+        vector_store_service.index.delete.assert_called_once_with(ids=embedding_ids)
+        assert success is True
+    
+    def test_search_pagination(self, vector_store_service, sample_embedding):
+        """Test paginated search results"""
+        # This would test pagination if implemented
+        # Implementation depends on how pagination is handled in the vector store
+        pass
+    
+    def test_vector_dimension_validation(self, vector_store_service):
+        """Test validation of embedding dimensions"""
+        # Test with wrong dimension
+        wrong_dimension_embedding = np.random.rand(256).tolist()  # Wrong size
+        
+        with pytest.raises(ValueError):
+            vector_store_service.store_embedding(
+                image_id=str(ObjectId()),
+                embedding=wrong_dimension_embedding,
+                metadata={}
+            )
+    
+    def test_connection_error_handling(self, vector_store_service):
+        """Test handling of connection errors"""
+        # Mock connection error
+        vector_store_service.index.query.side_effect = Exception("Connection failed")
+        
+        # Search should handle the error gracefully
+        with pytest.raises(Exception):
+            vector_store_service.search_similar(
+                query_embedding=[0.1] * 512,
+                team_id=str(ObjectId()),
+                top_k=10
+            )
+    
+    def test_empty_search_results(self, vector_store_service, sample_embedding):
+        """Test handling of empty search results"""
+        # Mock empty results
+        vector_store_service.index.query.return_value = {'matches': []}
+        
+        # Search should return empty list
+        results = vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=str(ObjectId()),
+            top_k=10
+        )
+        
+        assert results == []
+
+
+class TestVectorStoreIntegration:
+    """Integration tests for vector store with other services"""
+    
+    def test_embedding_lifecycle(self, vector_store_service, sample_embedding, sample_image):
+        """Test complete embedding lifecycle: store, search, update, delete"""
+        # Store embedding
+        embedding_id = vector_store_service.store_embedding(
+            image_id=str(sample_image.id),
+            embedding=sample_embedding,
+            metadata={'filename': sample_image.filename}
+        )
+        
+        # Search for similar embeddings
+        mock_results = {
+            'matches': [
+                {
+                    'id': embedding_id,
+                    'score': 1.0,
+                    'metadata': {'image_id': str(sample_image.id)}
+                }
+            ]
+        }
+        vector_store_service.index.query.return_value = mock_results
+        
+        results = vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=str(sample_image.team_id),
+            top_k=1
+        )
+        
+        assert len(results) == 1
+        assert results[0]['id'] == embedding_id
+        
+        # Delete embedding
+        success = vector_store_service.delete_embedding(embedding_id)
+        assert success is True
+    
+    def test_team_isolation(self, vector_store_service, sample_embedding):
+        """Test that team data is properly isolated"""
+        team1_id = str(ObjectId())
+        team2_id = str(ObjectId())
+        
+        # Mock search results that should be filtered by team
+        mock_results = {
+            'matches': [
+                {
+                    'id': 'emb1',
+                    'score': 0.9,
+                    'metadata': {'image_id': '1', 'team_id': team1_id}
+                },
+                {
+                    'id': 'emb2',
+                    'score': 0.8,
+                    'metadata': {'image_id': '2', 'team_id': team2_id}
+                }
+            ]
+        }
+        vector_store_service.index.query.return_value = mock_results
+        
+        # Search for team1 should only return team1 results
+        results = vector_store_service.search_similar(
+            query_embedding=sample_embedding,
+            team_id=team1_id,
+            top_k=10
+        )
+        
+        # Verify team filter was applied in the query
+        call_args = vector_store_service.index.query.call_args
+        assert 'filter' in call_args[1]
+        assert call_args[1]['filter']['team_id'] == team1_id 
\ No newline at end of file