diff --git a/litellm/proxy/_experimental/mcp_server/oauth2_token_cache.py b/litellm/proxy/_experimental/mcp_server/oauth2_token_cache.py
index 0592f083c40..d7f098908a4 100644
--- a/litellm/proxy/_experimental/mcp_server/oauth2_token_cache.py
+++ b/litellm/proxy/_experimental/mcp_server/oauth2_token_cache.py
@@ -27,11 +27,21 @@ from litellm.proxy.common_utils.encrypt_decrypt_utils import (
     encrypt_value_helper,
 )
 from litellm.proxy._experimental.mcp_server.auth import token_exchange
-from litellm.proxy._experimental.mcp_server.v2_resolver_bridge import (
-    resolve_v2_auth_value,
-)
 from litellm.types.llms.custom_http import httpxSpecialProvider
 
+# The v2 resolver bridge pulls in the v2 gateway package (and its `expression` dependency).
+# Guard the import so a missing optional dep degrades this graft to v1 rather than taking down
+# the entire MCP feature on startup.
+try:
+    from litellm.proxy._experimental.mcp_server.v2_resolver_bridge import (
+        resolve_v2_auth_value,
+    )
+except ImportError as _e:
+    verbose_logger.warning(
+        "v2 MCP resolver bridge unavailable (%s); using v1 resolution", _e
+    )
+    resolve_v2_auth_value = None  # type: ignore[assignment]
+
 if TYPE_CHECKING:
     from litellm.types.mcp_server.mcp_server_manager import MCPServer
 
@@ -290,9 +300,10 @@ async def resolve_mcp_auth(
     """
     if mcp_auth_header:
         return mcp_auth_header
-    v2_auth_value = await resolve_v2_auth_value(server)
-    if v2_auth_value is not None:
-        return v2_auth_value
+    if resolve_v2_auth_value is not None:
+        v2_auth_value = await resolve_v2_auth_value(server)
+        if v2_auth_value is not None:
+            return v2_auth_value
     if server.has_token_exchange_config:
         if subject_token:
             return await token_exchange.mcp_token_exchange_handler.exchange_token(
diff --git a/uv.lock b/uv.lock
index 5339b56df7f..6e9b44e9727 100644
--- a/uv.lock
+++ b/uv.lock
@@ -9,7 +9,7 @@ resolution-markers = [
 ]
 
 [options]
-exclude-newer = "2026-06-14T15:53:04.946308996Z"
+exclude-newer = "0001-01-01T00:00:00Z" # This has no effect and is included for backwards compatibility when using relative exclude-newer values.
 exclude-newer-span = "P3D"
 
 [manifest]
@@ -1477,6 +1477,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/c1/ea/53f2148663b321f21b5a606bd5f191517cf40b7072c0497d3c92c4a13b1e/executing-2.2.1-py2.py3-none-any.whl", hash = "sha256:760643d3452b4d777d295bb167ccc74c64a81df23fb5e08eff250c425a4b2017", size = 28317, upload-time = "2025-09-01T09:48:08.5Z" },
 ]
 
+[[package]]
+name = "expression"
+version = "5.6.0"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "typing-extensions" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/43/c7/bb061623b5815566bda69f5e9d156e38a97ebb383b8db3d2dedb26415466/expression-5.6.0.tar.gz", hash = "sha256:454f6fe138347194a43c7f878d958efe9b84b9cc770e462010c7a52e18058065", size = 59147, upload-time = "2025-02-19T09:37:37.432Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/6b/a2/656b8bebe495117342a8676ccabf52b3885ce11a856c8dfe1fbbdc250d2d/expression-5.6.0-py3-none-any.whl", hash = "sha256:f5c62e38186c9287e088dee9cf3939b0bbde21cb4c59571872154a53d33dd7c0", size = 69673, upload-time = "2025-02-19T09:37:35.476Z" },
+]
+
 [[package]]
 name = "fakeredis"
 version = "2.34.1"
@@ -3285,6 +3297,7 @@ proxy = [
     { name = "backoff" },
     { name = "boto3" },
     { name = "cryptography" },
+    { name = "expression" },
     { name = "fastapi" },
     { name = "fastapi-sso" },
     { name = "granian" },
@@ -3446,6 +3459,7 @@ requires-dist = [
     { name = "ddtrace", marker = "extra == 'proxy-runtime'", specifier = ">=2.19.0,<3.0" },
     { name = "detect-secrets", marker = "extra == 'proxy-runtime'", specifier = ">=1.5.0,<2.0" },
     { name = "diskcache", marker = "extra == 'caching'", specifier = ">=5.6.3,<6.0" },
+    { name = "expression", marker = "extra == 'proxy'", specifier = ">=5.6.0,<6.0" },
     { name = "fastapi", marker = "extra == 'proxy'", specifier = ">=0.136.3,<1.0" },
     { name = "fastapi-sso", marker = "extra == 'proxy'", specifier = ">=0.19.0,<1.0" },
     { name = "fastuuid", specifier = ">=0.14.0,<1.0" },