From 56ef1ed00311b94368c45b24f2839ef2fb761a83 Mon Sep 17 00:00:00 2001
From: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
Date: Tue, 5 May 2026 20:11:25 +0000
Subject: [PATCH] Align preview HTTP method order with
 register_tools_from_openapi

The preview endpoint and register_tools_from_openapi both use
order-dependent collision disambiguation (_2, _3 suffixes). When the
iteration order differs, two operations on the same path with sanitized
names that collide get different suffixes in preview vs registration,
so the dashboard shows names that don't match what actually got
registered.

Also adds a regression test that fails on the swapped order.

Co-authored-by: Mateo Wang <mateo-berri@users.noreply.github.com>
---
 .../mcp_server/rest_endpoints.py              |  2 +-
 .../mcp_server/test_rest_endpoints.py         | 90 +++++++++++++++++++
 2 files changed, 91 insertions(+), 1 deletion(-)

diff --git a/litellm/proxy/_experimental/mcp_server/rest_endpoints.py b/litellm/proxy/_experimental/mcp_server/rest_endpoints.py
index 806bb132392..829863d2dbb 100644
--- a/litellm/proxy/_experimental/mcp_server/rest_endpoints.py
+++ b/litellm/proxy/_experimental/mcp_server/rest_endpoints.py
@@ -990,7 +990,7 @@ if MCP_AVAILABLE:
             tools: List[dict] = []
             used_names: set = set()
             for path, path_item in paths.items():
-                for method in ("get", "post", "put", "patch", "delete"):
+                for method in ("get", "post", "put", "delete", "patch"):
                     operation = path_item.get(method)
                     if operation is None:
                         continue
diff --git a/tests/test_litellm/proxy/_experimental/mcp_server/test_rest_endpoints.py b/tests/test_litellm/proxy/_experimental/mcp_server/test_rest_endpoints.py
index 68787d7a668..f4feac68fcc 100644
--- a/tests/test_litellm/proxy/_experimental/mcp_server/test_rest_endpoints.py
+++ b/tests/test_litellm/proxy/_experimental/mcp_server/test_rest_endpoints.py
@@ -1447,3 +1447,93 @@ class TestPreviewOpenAPITools:
             ), f"preview tool name {name!r} violates ^[a-zA-Z0-9_-]+$"
         assert "actions_download-job-logs-for-workflow-run" in names
         assert "pulls_list-files" in names
+
+    async def test_preview_method_order_matches_registration(self, monkeypatch):
+        """Preview must iterate HTTP methods in the same order as
+        register_tools_from_openapi, otherwise collision-disambiguation
+        suffixes (_2, _3, ...) get assigned to different operations and the
+        dashboard shows names that differ from what's actually registered.
+        """
+        from litellm.proxy._experimental.mcp_server import (
+            openapi_to_mcp_generator,
+        )
+
+        spec = {
+            "paths": {
+                "/items/{id}": {
+                    "delete": {
+                        "operationId": "items/delete",
+                        "summary": "Delete item",
+                    },
+                    "patch": {
+                        "operationId": "items.delete",
+                        "summary": "Soft-delete item",
+                    },
+                }
+            }
+        }
+
+        async def fake_load_spec(spec_path):  # noqa: ANN001
+            return spec
+
+        monkeypatch.setattr(
+            openapi_to_mcp_generator,
+            "load_openapi_spec_async",
+            fake_load_spec,
+            raising=False,
+        )
+
+        payload = NewMCPServerRequest(
+            server_name="collision_openapi_mcp",
+            spec_path="https://example.invalid/openapi.json",
+            transport="http",
+        )
+        request = _build_request()
+        from litellm.proxy._types import LitellmUserRoles
+
+        result = await rest_endpoints.test_tools_list(
+            request,
+            payload,
+            user_api_key_dict=UserAPIKeyAuth(user_role=LitellmUserRoles.PROXY_ADMIN),
+        )
+        assert result.get("error") is None, result
+        preview_summary_to_name = {t["description"]: t["name"] for t in result["tools"]}
+
+        registered_summary_to_name: dict = {}
+
+        def fake_create_tool_function(
+            path, method, operation, base_url
+        ):  # noqa: ANN001
+            def _f():
+                return None
+
+            return _f
+
+        monkeypatch.setattr(
+            openapi_to_mcp_generator,
+            "create_tool_function",
+            fake_create_tool_function,
+        )
+
+        class _StubRegistry:
+            def register_tool(
+                self, name, description, input_schema, handler
+            ):  # noqa: ANN001
+                registered_summary_to_name[description] = name
+
+        monkeypatch.setattr(
+            openapi_to_mcp_generator,
+            "global_mcp_tool_registry",
+            _StubRegistry(),
+        )
+
+        openapi_to_mcp_generator.register_tools_from_openapi(
+            spec, base_url="https://example.invalid"
+        )
+
+        assert preview_summary_to_name == registered_summary_to_name, (
+            f"preview {preview_summary_to_name} != "
+            f"registered {registered_summary_to_name} — method iteration "
+            "order is out of sync, so collision suffixes (_2, _3, ...) "
+            "land on different operations"
+        )