From ee76c9a6f4fbdf9975bf13154eb4982c1e86dc76 Mon Sep 17 00:00:00 2001 From: "devin-ai-integration[bot]" <158243242+devin-ai-integration[bot]@users.noreply.github.com> Date: Wed, 26 Aug 2026 20:45:51 -0700 Subject: [PATCH] fix(mcp): accept raw x-litellm-api-key on streamable HTTP admission (#38364) * fix(mcp): accept raw x-litellm-api-key on streamable HTTP admission Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com> * chore(mcp): drop comments restating parser behavior Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com> --------- Co-authored-by: yassin Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com> --- .../mcp_server/auth/user_api_key_auth_mcp.py | 6 +++- .../auth/test_user_api_key_auth_mcp.py | 33 +++++++++++++++++-- 2 files changed, 35 insertions(+), 4 deletions(-) diff --git a/litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py b/litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py index 281a555dc5c..bd8dfea3621 100644 --- a/litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py +++ b/litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py @@ -46,6 +46,7 @@ from litellm.proxy._types import ( ) from litellm.proxy.auth.ip_address_utils import IPAddressUtils from litellm.proxy.auth.user_api_key_auth import ( + _get_bearer_token_or_received_api_key, # pyright: ignore[reportPrivateUsage] # shared x-litellm-api-key parser lives with user_api_key_auth _run_centralized_common_checks, user_api_key_auth, ) @@ -429,7 +430,10 @@ class MCPRequestHandler: # An explicit x-litellm-api-key is always a LiteLLM credential, even # for a delegated server, so validate it: identity / spend / rate # limits resolve and any stored upstream token can be forwarded. - validated_user_api_key_auth = await user_api_key_auth(api_key=litellm_api_key, request=request) + validated_user_api_key_auth = await user_api_key_auth( + api_key=f"Bearer {_get_bearer_token_or_received_api_key(litellm_api_key)}", + request=request, + ) elif MCPRequestHandler._target_servers_delegate_auth_to_upstream( path=request_route, mcp_servers=mcp_servers, diff --git a/tests/test_litellm/proxy/_experimental/mcp_server/auth/test_user_api_key_auth_mcp.py b/tests/test_litellm/proxy/_experimental/mcp_server/auth/test_user_api_key_auth_mcp.py index 99e3e8d7413..aa6ddbfb49d 100644 --- a/tests/test_litellm/proxy/_experimental/mcp_server/auth/test_user_api_key_auth_mcp.py +++ b/tests/test_litellm/proxy/_experimental/mcp_server/auth/test_user_api_key_auth_mcp.py @@ -1082,11 +1082,38 @@ class TestMCPOAuth2AuthFlow: # LiteLLM key should be used for auth mock_auth.assert_called_once() call_args = mock_auth.call_args - assert call_args.kwargs["api_key"] == "sk-litellm-valid-key" + assert call_args.kwargs["api_key"] == "Bearer sk-litellm-valid-key" # OAuth2 headers should still contain the Authorization token assert oauth2_headers.get("Authorization") == "Bearer atlassian-oauth2-token" + @pytest.mark.parametrize( + "header_value", + [b"sk-litellm-valid-key", b"Bearer sk-litellm-valid-key", b"bearer sk-litellm-valid-key"], + ) + async def test_x_litellm_api_key_survives_bearer_only_strip(self, header_value): + from litellm.proxy.auth.user_api_key_auth import _get_bearer_token + + scope = { + "type": "http", + "method": "POST", + "path": "/mcp/some_server", + "headers": [(b"x-litellm-api-key", header_value)], + } + + async def mock_user_api_key_auth(api_key, request): + return UserAPIKeyAuth(api_key=api_key, user_id="test-user") + + with patch( # test-quality-ok: capturing the exact api_key handed to key validation is the regression under test + "litellm.proxy._experimental.mcp_server.auth.user_api_key_auth_mcp.user_api_key_auth", + side_effect=mock_user_api_key_auth, + ) as mock_auth: + auth_result, *_rest = await MCPRequestHandler.process_mcp_request(scope) + + mock_auth.assert_called_once() + assert _get_bearer_token(api_key=mock_auth.call_args.kwargs["api_key"]) == "sk-litellm-valid-key" + assert auth_result.user_id == "test-user" + async def test_litellm_key_in_authorization_backward_compat(self): """ Backward compatibility: when only Authorization header is present @@ -3007,7 +3034,7 @@ class TestMCPCustomHeaderName: # Verify the mock was called mock_auth.assert_called_once() call_args = mock_auth.call_args - assert call_args.kwargs["api_key"] == "test-api-key" + assert call_args.kwargs["api_key"] == "Bearer test-api-key" def test_get_mcp_server_auth_headers_from_headers(self): """Test _get_mcp_server_auth_headers_from_headers method""" @@ -6254,7 +6281,7 @@ class TestMCPDcrBridgeDelegateAdmission: ) = await MCPRequestHandler.process_mcp_request(scope) mock_auth.assert_called_once() - assert mock_auth.call_args.kwargs["api_key"] == "sk-explicit-litellm-key" + assert mock_auth.call_args.kwargs["api_key"] == "Bearer sk-explicit-litellm-key" # The explicit-key arm admitted; the envelope arm never ran, so no inner token is injected. assert auth_result.user_id == "litellm-key-user" assert mcp_server_auth_headers == {}