diff --git a/tests/integration/_support/conformance.py b/tests/integration/_support/conformance.py
index 82317850081..ef0ae6ff66a 100644
--- a/tests/integration/_support/conformance.py
+++ b/tests/integration/_support/conformance.py
@@ -1,4 +1,5 @@
 import hashlib
+import json
 import os
 import queue
 import signal
@@ -115,7 +116,7 @@ def reference_server(root: Path, directory: Path, port: int) -> Iterator["McpPee
 
 
 @contextmanager
-def authenticated_endpoint(target: str, key: str) -> Iterator[str]:
+def authenticated_endpoint(target: str, key: str, alias: str) -> Iterator[str]:
     from integration._support.asgi import asgi_server
     from starlette.applications import Starlette
     from starlette.requests import Request
@@ -125,10 +126,13 @@ def authenticated_endpoint(target: str, key: str) -> Iterator[str]:
 
     async def forward(scope: Scope, receive: Receive, send: Send) -> None:
         request: Final = Request(scope, receive)
+        original: Final = await request.body()
+        body: Final = prefixed_request(original, alias)
         headers: Final = tuple(
-            (name, value) for name, value in request.headers.raw if name.lower() != b"authorization"
+            (name, value)
+            for name, value in request.headers.raw
+            if name.lower() != b"authorization" and (name.lower() != b"content-length" or body == original)
         ) + ((b"authorization", f"Bearer {key}".encode()),)
-        body: Final = await request.body()
         async with httpx.AsyncClient(timeout=35, trust_env=False) as client:
             async with client.stream(request.method, target, headers=headers, content=body) as response:
                 streamed: Final = StreamingResponse(response.aiter_raw(), status_code=response.status_code)
@@ -141,3 +145,16 @@ def authenticated_endpoint(target: str, key: str) -> Iterator[str]:
 
     with asgi_server(Starlette(routes=[Mount("/mcp", app=forward)])) as url:
         yield url + "/mcp/"
+
+
+def prefixed_request(body: bytes, alias: str) -> bytes:
+    try:
+        request: Final = json.loads(body)
+    except (ValueError, UnicodeDecodeError):
+        return body
+    if not isinstance(request, dict) or request.get("method") not in ("tools/call", "prompts/get"):
+        return body
+    params: Final = request.get("params")
+    if not isinstance(params, dict) or not isinstance(params.get("name"), str):
+        return body
+    return json.dumps({**request, "params": {**params, "name": f"{alias}-{params['name']}"}}).encode()
diff --git a/tests/integration/mcp/test_mcp_official_conformance.py b/tests/integration/mcp/test_mcp_official_conformance.py
index 0877fc9457e..c0375b4223e 100644
--- a/tests/integration/mcp/test_mcp_official_conformance.py
+++ b/tests/integration/mcp/test_mcp_official_conformance.py
@@ -19,7 +19,7 @@ def test_official_scenario_through_gateway(gateway: Gateway, tmp_path: Path, unu
         key: Final = scenario.key(object_permission={"mcp_servers": [identity]})
         direct: Final = run_scenario(root, reference.url, name, output / "direct")
         endpoint: Final = str(gateway.client.base_url).rstrip("/") + f"/{alias}/mcp"
-        with authenticated_endpoint(endpoint, key) as authenticated:
+        with authenticated_endpoint(endpoint, key, alias) as authenticated:
             proxied: Final = run_scenario(root, authenticated, name, output / "gateway")
         assert tuple(check.status for check in direct if check.id == name) == ("SUCCESS",)
         assert tuple(check.status for check in proxied if check.id == name) == ("SUCCESS",)
diff --git a/tests/unit/integration_support/test_conformance.py b/tests/unit/integration_support/test_conformance.py
index c7b0795479f..23d950938db 100644
--- a/tests/unit/integration_support/test_conformance.py
+++ b/tests/unit/integration_support/test_conformance.py
@@ -4,7 +4,7 @@ from pathlib import Path
 from typing import Final
 
 import pytest
-from tests.integration._support.conformance import read_checks, verify_archive
+from tests.integration._support.conformance import read_checks, verify_archive, prefixed_request
 from pydantic import ValidationError
 
 
@@ -97,3 +97,29 @@ def test_official_text_success_requires_the_reference_payload(tmp_path: Path) ->
         )
     )
     assert read_checks(tmp_path, "tools-call-simple-text")[0].status == "SUCCESS"
+
+
+@pytest.mark.parametrize("method", ("tools/call", "prompts/get"))
+def test_only_fixture_name_is_translated_to_advertised_name(method: str) -> None:
+    request: Final = {
+        "jsonrpc": "2.0",
+        "id": 4,
+        "method": method,
+        "params": {"name": "test_tool", "_meta": {"progressToken": "keep"}},
+    }
+    changed: Final = json.loads(prefixed_request(json.dumps(request).encode(), "official"))
+    assert changed == {**request, "params": {"name": "official-test_tool", "_meta": {"progressToken": "keep"}}}
+    assert "arguments" not in changed["params"]
+
+
+@pytest.mark.parametrize(
+    "body",
+    (
+        b"malformed JSON",
+        b"[]",
+        b'{"method":"initialize","params":{"protocolVersion":"2025-03-26"}}',
+        b'{"method":"tools/call","params":{"name":17}}',
+    ),
+)
+def test_name_integration_preserves_other_requests(body: bytes) -> None:
+    assert prefixed_request(body, "official") == body