diff --git a/docs/doctoring/gateway-route-proof-not-cli-rendering-20260930.md b/docs/doctoring/gateway-route-proof-not-cli-rendering-20260930.md
new file mode 100644
index 0000000000..a09925febf
--- /dev/null
+++ b/docs/doctoring/gateway-route-proof-not-cli-rendering-20260930.md
@@ -0,0 +1,28 @@
+# Gateway route proof and CLI rendering
+
+The executed route test introduced in `9c6d05374` correctly observes the
+installed OpenCode CLI's request URL, but its negative case additionally
+required `not found` to appear in CLI output before fixture cleanup. On a busy
+host the expected `/chat/completions` request and gateway 404 occurred without
+that display text. A full run therefore failed with 5,176 other tests passing,
+while the same two CLI tests separately passed in 47.70 seconds.
+
+The fixture intentionally stops the CLI after observing a request; that is
+transport evidence, not a terminal CLI error-rendering receipt. No production
+request timeout, provider retry, review verdict, or sanitizer is changed.
+
+The repair records HTTP statuses only after the stub writes its response.
+The real installed CLI must still request `/v1/chat/completions` for the shipped
+configuration and `/chat/completions` for the bare-origin regression. Those
+requests must respectively receive a sent 200 and 404 response. Delayed or
+redacted CLI text is no longer confused with the network path. The stub retains
+the pinned gateway's error body; this does not require production logs to expose
+raw provider errors.
+
+Before repair: the unchanged negative case failed at the display-text assertion.
+After repair: both real CLI cases passed in 40.56 seconds. The complete suite
+and current-head hosted evidence remain separate acceptance steps.
+
+This is an inherited test-reliability repair, separated from the Noema
+input-modality catalog change. It is not a security-finding exception or proof
+that any provider HTTP 400 incident has been resolved.
diff --git a/tests/test_opencode_gateway_route_integration.py b/tests/test_opencode_gateway_route_integration.py
index 3893914c0e..c1560872c7 100644
--- a/tests/test_opencode_gateway_route_integration.py
+++ b/tests/test_opencode_gateway_route_integration.py
@@ -8,9 +8,10 @@
 
 These tests run the installed OpenCode CLI against a stub that answers exactly
 like the vendored gateway — the served route succeeds, every other route 404s
-with the gateway's own wording — and record which path the CLI asked for. The
-tracked ``opencode.jsonc`` provider block is the input, so the proof follows
-the shipped config instead of a copy of it.
+with the gateway's own wording — and record the requested path and sent status.
+The tracked ``opencode.jsonc`` provider block is the input, so the proof follows
+the shipped config instead of a copy of it. CLI error rendering is not a
+transport receipt and can lag the response on a busy host.
 
 They skip when no ``opencode`` binary is present (CI images for the quality
 workflows do not install it); local execution is the evidence.
@@ -52,6 +53,7 @@ class _GatewayStub(BaseHTTPRequestHandler):
     """Answer like the vendored gateway: one served route, 404 elsewhere."""
 
     requested_paths: list[str] = []
+    responses: list[tuple[str, int]] = []
 
     def do_POST(self) -> None:  # noqa: N802 - BaseHTTPRequestHandler API
         """Record the requested path and answer as the gateway would."""
@@ -92,6 +94,7 @@ def _send(self, status: int, payload: dict) -> None:
         self.send_header("content-length", str(len(body)))
         self.end_headers()
         self.wfile.write(body)
+        type(self).responses.append((self.path, status))
 
     def log_message(self, *args: object) -> None:
         """Silence the default stderr access log."""
@@ -101,6 +104,7 @@ def log_message(self, *args: object) -> None:
 def gateway_stub_fixture():
     """Serve the gateway stub on a loopback port for one test."""
     _GatewayStub.requested_paths = []
+    _GatewayStub.responses = []
     server = HTTPServer(("127.0.0.1", 0), _GatewayStub)
     thread = threading.Thread(target=server.serve_forever, daemon=True)
     thread.start()
@@ -190,15 +194,15 @@ def test_tracked_config_requests_the_gateway_served_route(gateway_stub, tmp_path
     _run_opencode(tmp_path, base_url, origin, requested_paths)
     assert requested_paths, "the CLI issued no request to the gateway stub"
     assert requested_paths[0] == GATEWAY_SERVED_ROUTE
+    assert _GatewayStub.responses[0] == (GATEWAY_SERVED_ROUTE, 200)
 
 
 def test_bare_origin_reproduces_the_route_not_found_outage(gateway_stub, tmp_path) -> None:
-    """Dropping /v1 must reproduce the unserved path and the gateway wording."""
+    """Dropping /v1 must request an unserved path for which the stub sends 404."""
     origin, requested_paths = gateway_stub
     bare = "{env:CONTEXTUAL_ORCHESTRATOR_BASE_URL}"
-    stdout, stderr = _run_opencode(tmp_path, bare, origin, requested_paths)
+    _run_opencode(tmp_path, bare, origin, requested_paths)
     assert requested_paths, "the CLI issued no request to the gateway stub"
     assert requested_paths[0] == "/chat/completions"
     assert requested_paths[0] != GATEWAY_SERVED_ROUTE
-    combined = f"{stdout}\n{stderr}".casefold()
-    assert GATEWAY_ROUTE_NOT_FOUND_MESSAGE in combined
+    assert _GatewayStub.responses[0] == ("/chat/completions", 404)