From e8090028f3718373a09e7ecfd9087e59523c5b0d Mon Sep 17 00:00:00 2001
From: Tin Chi Lo <tin@berri.ai>
Date: Mon, 13 Jul 2026 16:14:54 -0700
Subject: [PATCH] style(mcp): unquote annotations and use PEP 604 unions in the
 faults package

---
 litellm/proxy/_experimental/mcp_server/faults/classify.py   | 2 +-
 .../proxy/_experimental/mcp_server/faults/render_oauth.py   | 2 +-
 litellm/proxy/_experimental/mcp_server/faults/types.py      | 6 +++---
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/litellm/proxy/_experimental/mcp_server/faults/classify.py b/litellm/proxy/_experimental/mcp_server/faults/classify.py
index a816b8e2a96..cf4d022d33b 100644
--- a/litellm/proxy/_experimental/mcp_server/faults/classify.py
+++ b/litellm/proxy/_experimental/mcp_server/faults/classify.py
@@ -35,7 +35,7 @@ def _safe_json(response: httpx.Response) -> object:
         return None
 
 
-def _bounded_field(value: object) -> "str | None":
+def _bounded_field(value: object) -> str | None:
     if not isinstance(value, str) or not value:
         return None
     return value[:MAX_WIRE_FIELD_CHARS]
diff --git a/litellm/proxy/_experimental/mcp_server/faults/render_oauth.py b/litellm/proxy/_experimental/mcp_server/faults/render_oauth.py
index 5fc82819dc0..4856e6fbe52 100644
--- a/litellm/proxy/_experimental/mcp_server/faults/render_oauth.py
+++ b/litellm/proxy/_experimental/mcp_server/faults/render_oauth.py
@@ -58,7 +58,7 @@ def render_token_fault(fault: UpstreamOAuthFault) -> JSONResponse:
             assert_never(fault.tag)
 
 
-def dcr_fault_detail(fault: UpstreamOAuthFault) -> "tuple[int, str]":
+def dcr_fault_detail(fault: UpstreamOAuthFault) -> tuple[int, str]:
     """Status and detail string for a registration fault, raised as HTTPException by the caller.
     RFC 7591 §3.2.2 defines registration errors as 400, so a contract-conformant rejection is 400
     regardless of the status the upstream chose; everything else is a 502 upstream fault."""
diff --git a/litellm/proxy/_experimental/mcp_server/faults/types.py b/litellm/proxy/_experimental/mcp_server/faults/types.py
index 2a200323024..8cc291459a0 100644
--- a/litellm/proxy/_experimental/mcp_server/faults/types.py
+++ b/litellm/proxy/_experimental/mcp_server/faults/types.py
@@ -7,7 +7,7 @@ when an upstream's status and error code are relayed independently.
 
 from __future__ import annotations
 
-from typing import Literal, Optional, TypeAlias
+from typing import Literal, TypeAlias
 
 from pydantic import BaseModel, ConfigDict
 
@@ -33,8 +33,8 @@ class CallerRejected(BaseModel):
     model_config = ConfigDict(frozen=True)
     tag: Literal["caller_rejected"] = "caller_rejected"
     code: str
-    description: Optional[str] = None
-    error_uri: Optional[str] = None
+    description: str | None = None
+    error_uri: str | None = None
 
 
 class GatewayCredentialsRejected(BaseModel):