diff --git a/tests/server/auth/oauth_proxy/conftest.py b/tests/server/auth/oauth_proxy/conftest.py
index 3acfacf7f..802ca2348 100644
--- a/tests/server/auth/oauth_proxy/conftest.py
+++ b/tests/server/auth/oauth_proxy/conftest.py
@@ -288,6 +288,8 @@ def jwt_verifier():
 @pytest.fixture
 def oauth_proxy(jwt_verifier):
     """Create a standard OAuthProxy instance for testing."""
+    from key_value.aio.stores.memory import MemoryStore
+
     return OAuthProxy(
         upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
         upstream_token_endpoint="https://github.com/login/oauth/access_token",
@@ -297,6 +299,7 @@ def oauth_proxy(jwt_verifier):
         base_url="https://myserver.com",
         redirect_path="/auth/callback",
         jwt_signing_key="test-secret",
+        client_storage=MemoryStore(),
     )
 
 
diff --git a/tests/server/auth/oauth_proxy/test_authorization.py b/tests/server/auth/oauth_proxy/test_authorization.py
index 2b5aaf4a2..7a8a9b9e7 100644
--- a/tests/server/auth/oauth_proxy/test_authorization.py
+++ b/tests/server/auth/oauth_proxy/test_authorization.py
@@ -3,6 +3,7 @@
 from urllib.parse import parse_qs, urlparse
 
 import pytest
+from key_value.aio.stores.memory import MemoryStore
 from mcp.server.auth.provider import AuthorizationParams
 from mcp.shared.auth import OAuthClientInformationFull
 from pydantic import AnyUrl
@@ -67,6 +68,7 @@ class TestOAuthProxyPKCE:
             base_url="https://proxy.example.com",
             forward_pkce=True,
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
     @pytest.fixture
@@ -82,6 +84,7 @@ class TestOAuthProxyPKCE:
             base_url="https://proxy.example.com",
             forward_pkce=False,
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
     async def test_pkce_forwarding_enabled(self, proxy_with_pkce):
@@ -172,6 +175,7 @@ class TestParameterForwarding:
                 "prompt": "consent",
                 "max_age": "3600",
             },
+            client_storage=MemoryStore(),
         )
 
         client = OAuthClientInformationFull(
diff --git a/tests/server/auth/oauth_proxy/test_config.py b/tests/server/auth/oauth_proxy/test_config.py
index ae3abe002..0b88a0ae5 100644
--- a/tests/server/auth/oauth_proxy/test_config.py
+++ b/tests/server/auth/oauth_proxy/test_config.py
@@ -1,6 +1,7 @@
 """Tests for OAuth proxy configuration and validation."""
 
 import pytest
+from key_value.aio.stores.memory import MemoryStore
 from mcp.server.auth.provider import AuthorizationParams, AuthorizeError
 from mcp.shared.auth import OAuthClientInformationFull
 from pydantic import AnyHttpUrl, AnyUrl
@@ -76,6 +77,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         # Use non-default path to prove fix isn't relying on old hardcoded /mcp
         proxy.set_mcp_path("/api/v2/mcp")
@@ -261,6 +263,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         proxy.set_mcp_path("/mcp")
         # Simulate server configured with query params for tenant scoping
@@ -300,6 +303,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         proxy.set_mcp_path("/mcp")
         # Simulate server configured with query params for tenant scoping
@@ -337,6 +341,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         proxy.set_mcp_path("/mcp")
         # Simulate server configured with query params for tenant scoping
@@ -374,6 +379,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Before set_mcp_path, _jwt_issuer is None
@@ -397,6 +403,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         proxy.set_mcp_path(None)
@@ -413,6 +420,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         with pytest.raises(RuntimeError) as exc_info:
@@ -430,6 +438,7 @@ class TestResourceURLValidation:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Before get_routes, _jwt_issuer is None
diff --git a/tests/server/auth/oauth_proxy/test_e2e.py b/tests/server/auth/oauth_proxy/test_e2e.py
index 8b500db61..39c4592e8 100644
--- a/tests/server/auth/oauth_proxy/test_e2e.py
+++ b/tests/server/auth/oauth_proxy/test_e2e.py
@@ -5,6 +5,7 @@ from unittest.mock import AsyncMock, patch
 from urllib.parse import parse_qs, urlparse
 
 import httpx
+from key_value.aio.stores.memory import MemoryStore
 from mcp.server.auth.provider import AuthorizationCode, AuthorizationParams
 from mcp.shared.auth import OAuthClientInformationFull
 from pydantic import AnyUrl
@@ -30,6 +31,7 @@ class TestOAuthProxyE2E:
             token_verifier=MockTokenVerifier(),
             base_url="http://localhost:8000",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Create FastMCP server with proxy
@@ -84,6 +86,7 @@ class TestOAuthProxyE2E:
             token_verifier=MockTokenVerifier(),
             base_url="http://localhost:8000",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Initialize JWT issuer before token operations
@@ -201,6 +204,7 @@ class TestOAuthProxyE2E:
             base_url="http://localhost:8000",
             forward_pkce=True,  # Enable PKCE forwarding
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         client = OAuthClientInformationFull(
diff --git a/tests/server/auth/oauth_proxy/test_oauth_proxy.py b/tests/server/auth/oauth_proxy/test_oauth_proxy.py
index a8cfac54d..27c31e198 100644
--- a/tests/server/auth/oauth_proxy/test_oauth_proxy.py
+++ b/tests/server/auth/oauth_proxy/test_oauth_proxy.py
@@ -1,5 +1,7 @@
 """Tests for OAuth proxy initialization and configuration."""
 
+from key_value.aio.stores.memory import MemoryStore
+
 from fastmcp.server.auth.oauth_proxy import OAuthProxy
 
 
@@ -16,6 +18,7 @@ class TestOAuthProxyInitialization:
             token_verifier=jwt_verifier,
             base_url="https://api.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         assert (
@@ -45,6 +48,7 @@ class TestOAuthProxyInitialization:
             forward_pkce=False,
             token_endpoint_auth_method="client_secret_post",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         assert proxy._upstream_revocation_endpoint == "https://auth.example.com/revoke"
@@ -65,5 +69,6 @@ class TestOAuthProxyInitialization:
             base_url="https://api.com",
             redirect_path="auth/callback",  # No leading slash
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         assert proxy._redirect_path == "/auth/callback"
diff --git a/tests/server/auth/oauth_proxy/test_tokens.py b/tests/server/auth/oauth_proxy/test_tokens.py
index 5051a8ebc..b7e16431f 100644
--- a/tests/server/auth/oauth_proxy/test_tokens.py
+++ b/tests/server/auth/oauth_proxy/test_tokens.py
@@ -4,6 +4,7 @@ import time
 from unittest.mock import AsyncMock, Mock, patch
 
 import pytest
+from key_value.aio.stores.memory import MemoryStore
 from mcp.server.auth.handlers.token import TokenErrorResponse
 from mcp.server.auth.handlers.token import TokenHandler as SDKTokenHandler
 from mcp.server.auth.provider import AuthorizationCode
@@ -35,6 +36,7 @@ class TestOAuthProxyTokenEndpointAuth:
             base_url="https://proxy.example.com",
             token_endpoint_auth_method="client_secret_post",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         assert proxy_post._token_endpoint_auth_method == "client_secret_post"
 
@@ -48,6 +50,7 @@ class TestOAuthProxyTokenEndpointAuth:
             base_url="https://proxy.example.com",
             token_endpoint_auth_method="client_secret_basic",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         assert proxy_basic._token_endpoint_auth_method == "client_secret_basic"
 
@@ -60,6 +63,7 @@ class TestOAuthProxyTokenEndpointAuth:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
         assert proxy_default._token_endpoint_auth_method is None
 
@@ -74,6 +78,7 @@ class TestOAuthProxyTokenEndpointAuth:
             base_url="https://proxy.example.com",
             token_endpoint_auth_method="client_secret_post",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Initialize JWT issuer before token operations
@@ -296,6 +301,7 @@ class TestFallbackAccessTokenExpiry:
             base_url="http://localhost:8000",
             jwt_signing_key="test-signing-key",
             fallback_access_token_expiry_seconds=86400,
+            client_storage=MemoryStore(),
         )
 
         assert provider._fallback_access_token_expiry_seconds == 86400
@@ -313,6 +319,7 @@ class TestFallbackAccessTokenExpiry:
             ),
             base_url="http://localhost:8000",
             jwt_signing_key="test-signing-key",
+            client_storage=MemoryStore(),
         )
 
         assert provider._fallback_access_token_expiry_seconds is None
@@ -345,6 +352,7 @@ class TestUpstreamTokenStorageTTL:
             token_verifier=jwt_verifier,
             base_url="https://proxy.example.com",
             jwt_signing_key="test-secret-key",
+            client_storage=MemoryStore(),
         )
         proxy.set_mcp_path("/mcp")
         return proxy
diff --git a/tests/server/auth/oauth_proxy/test_ui.py b/tests/server/auth/oauth_proxy/test_ui.py
index 9967d5a31..4795ec2ff 100644
--- a/tests/server/auth/oauth_proxy/test_ui.py
+++ b/tests/server/auth/oauth_proxy/test_ui.py
@@ -2,6 +2,7 @@
 
 from unittest.mock import Mock
 
+from key_value.aio.stores.memory import MemoryStore
 from starlette.requests import Request
 from starlette.responses import HTMLResponse
 
@@ -76,6 +77,7 @@ class TestErrorPageRendering:
             ),
             base_url="http://localhost:8000",
             jwt_signing_key="test-signing-key",
+            client_storage=MemoryStore(),
         )
 
         # Mock a request with an error from the IdP
diff --git a/tests/server/auth/test_enhanced_error_responses.py b/tests/server/auth/test_enhanced_error_responses.py
index cec425ecc..f7463be36 100644
--- a/tests/server/auth/test_enhanced_error_responses.py
+++ b/tests/server/auth/test_enhanced_error_responses.py
@@ -29,6 +29,8 @@ class TestEnhancedAuthorizationHandler:
     @pytest.fixture
     def oauth_proxy(self, rsa_key_pair):
         """Create OAuth proxy for testing."""
+        from key_value.aio.stores.memory import MemoryStore
+
         return OAuthProxy(
             upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
             upstream_token_endpoint="https://github.com/login/oauth/access_token",
@@ -42,6 +44,7 @@ class TestEnhancedAuthorizationHandler:
             ),
             base_url="https://myserver.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
     def test_unregistered_client_returns_html_for_browser(self, oauth_proxy):
@@ -290,6 +293,8 @@ class TestContentNegotiation:
     @pytest.fixture
     def oauth_proxy(self):
         """Create OAuth proxy for testing."""
+        from key_value.aio.stores.memory import MemoryStore
+
         return OAuthProxy(
             upstream_authorization_endpoint="https://github.com/login/oauth/authorize",
             upstream_token_endpoint="https://github.com/login/oauth/access_token",
@@ -303,6 +308,7 @@ class TestContentNegotiation:
             ),
             base_url="https://myserver.com",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
     def test_html_preferred_when_both_accepted(self, oauth_proxy):
diff --git a/tests/server/auth/test_oauth_mounting.py b/tests/server/auth/test_oauth_mounting.py
index 1729c5979..93f4a2308 100644
--- a/tests/server/auth/test_oauth_mounting.py
+++ b/tests/server/auth/test_oauth_mounting.py
@@ -8,6 +8,7 @@ The fix uses MCP SDK 1.17+ which implements RFC 9728 path-scoped well-known URLs
 
 import httpx
 import pytest
+from key_value.aio.stores.memory import MemoryStore
 from pydantic import AnyHttpUrl
 from starlette.applications import Starlette
 from starlette.routing import Mount
@@ -220,6 +221,7 @@ class TestOAuthMounting:
             token_verifier=token_verifier,
             base_url="https://api.example.com/api",  # Includes mount prefix
             issuer_url="https://api.example.com",  # Root level
+            client_storage=MemoryStore(),
         )
 
         mcp = FastMCP("test-server", auth=auth_provider)
@@ -290,6 +292,7 @@ class TestOAuthMounting:
             upstream_client_secret="test-client-secret",
             token_verifier=token_verifier,
             base_url="https://api.example.com/api",  # Has path, no explicit issuer_url
+            client_storage=MemoryStore(),
         )
 
         mcp = FastMCP("test-server", auth=auth_provider)
@@ -366,6 +369,7 @@ class TestOAuthMounting:
             token_verifier=token_verifier,
             base_url="https://api.example.com/api",
             issuer_url="https://api.example.com",  # Explicitly root
+            client_storage=MemoryStore(),
         )
 
         well_known_routes = auth_provider.get_well_known_routes(mcp_path="/mcp")
diff --git a/tests/server/auth/test_oauth_proxy_redirect_validation.py b/tests/server/auth/test_oauth_proxy_redirect_validation.py
index c91560c52..336029197 100644
--- a/tests/server/auth/test_oauth_proxy_redirect_validation.py
+++ b/tests/server/auth/test_oauth_proxy_redirect_validation.py
@@ -1,6 +1,7 @@
 """Tests for OAuth proxy redirect URI validation."""
 
 import pytest
+from key_value.aio.stores.memory import MemoryStore
 from mcp.shared.auth import InvalidRedirectUriError
 from pydantic import AnyUrl
 
@@ -112,6 +113,7 @@ class TestOAuthProxyRedirectValidation:
             token_verifier=MockTokenVerifier(),
             base_url="http://localhost:8000",
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # The proxy should store None for default (allow all)
@@ -130,6 +132,7 @@ class TestOAuthProxyRedirectValidation:
             base_url="http://localhost:8000",
             allowed_client_redirect_uris=custom_patterns,
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         assert proxy._allowed_client_redirect_uris == custom_patterns
@@ -145,6 +148,7 @@ class TestOAuthProxyRedirectValidation:
             base_url="http://localhost:8000",
             allowed_client_redirect_uris=[],
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         assert proxy._allowed_client_redirect_uris == []
@@ -162,6 +166,7 @@ class TestOAuthProxyRedirectValidation:
             base_url="http://localhost:8000",
             allowed_client_redirect_uris=custom_patterns,
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Register a client
@@ -195,6 +200,7 @@ class TestOAuthProxyRedirectValidation:
             base_url="http://localhost:8000",
             allowed_client_redirect_uris=custom_patterns,
             jwt_signing_key="test-secret",
+            client_storage=MemoryStore(),
         )
 
         # Get an unregistered client