From 3b20b0a35bc45459d002ae4f85182d0eff7782ac Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?St=C3=A9phane=20Tailland?= <stephane@sttlab.eu>
Date: Sun, 23 Aug 2026 15:39:27 +0200
Subject: [PATCH] Revert stream-binding approach: merge GET into the single MCP
 route instead
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The second ai-mcp-proxy binding (added to fix the GET/SSE 502 loop)
created a second runtime plugin instance with the same tool config,
which ai-mcp-proxy's own duplicate-name detection caught: all three
tools (list-customers/get-customer/create-customer) fell back to
auto-generated names across both instances. Confirmed via dataplane
pod logs right after applying the previous fix.

Real fix: one KongRoute for all three MCP HTTP methods (GET/POST/
DELETE) instead of two, one ai-mcp-proxy binding instead of two.
ai-mcp-proxy already tolerates multi-method routes (same "skips
method selection" notice the existing POST+DELETE route already
produces) — extending to GET is the same class of thing, not new
risk, and there is now exactly one plugin instance so no duplicate
tool names.
---
 kong/mcp/pluginbindings.yaml | 31 -------------------------------
 kong/mcp/routes.yaml         | 35 ++++++++++++++---------------------
 2 files changed, 14 insertions(+), 52 deletions(-)

diff --git a/kong/mcp/pluginbindings.yaml b/kong/mcp/pluginbindings.yaml
index 9177773..0fa96a4 100644
--- a/kong/mcp/pluginbindings.yaml
+++ b/kong/mcp/pluginbindings.yaml
@@ -34,37 +34,6 @@ spec:
       kind: KongRoute
       name: ${NAME}-customers-mcp
 ---
-# Also bind to the GET/-stream route, not just the POST/DELETE one above.
-# Without this, GET requests never reach ai-mcp-proxy at all and fall
-# through to the KongService's own upstream target — which is
-# ${REST_HOSTNAME} (Kong's own external hostname, mcp/service.yaml), so an
-# unintercepted GET loops back into the Gateway and grows response headers
-# on every pass until nginx rejects it ("upstream sent too big header",
-# 502) — confirmed 2026-08-23 via customers dataplane pod logs (28
-# occurrences) while debugging a LibreChat connection failure specific to
-# customers-mcp. catalog-mcp has the identical gap (checked: its
-# ai-mcp-proxy-binding also targets only the non-stream route) but happens
-# to fail as a harmless 405 there instead of looping — not fixed here,
-# flagged in STATUS.md, don't assume catalog's GET stream actually works
-# just because nothing broke loudly.
-apiVersion: configuration.konghq.com/v1alpha1
-kind: KongPluginBinding
-metadata:
-  name: ${NAME}-customers-mcp-ai-mcp-proxy-stream-binding
-  namespace: ${NAMESPACE}
-spec:
-  controlPlaneRef:
-    type: konnectNamespacedRef
-    konnectNamespacedRef:
-      name: ${CONTROL_PLANE_REF_NAME}
-  pluginRef:
-    name: ${NAME}-customers-mcp-ai-mcp-proxy
-  targets:
-    routeRef:
-      group: configuration.konghq.com
-      kind: KongRoute
-      name: ${NAME}-customers-mcp-stream
----
 apiVersion: configuration.konghq.com/v1alpha1
 kind: KongPluginBinding
 metadata:
diff --git a/kong/mcp/routes.yaml b/kong/mcp/routes.yaml
index edb900d..83c268f 100644
--- a/kong/mcp/routes.yaml
+++ b/kong/mcp/routes.yaml
@@ -1,3 +1,16 @@
+# Single route for all three MCP HTTP methods (GET opens the SSE stream,
+# POST carries JSON-RPC, DELETE terminates the session) — deliberately NOT
+# split into two KongRoutes the way catalog-mcp does. ai-mcp-proxy is bound
+# once, to this one route (mcp/pluginbindings.yaml); a second route with
+# its own binding of the *same* KongPlugin creates a second runtime plugin
+# instance with the same tool names, and ai-mcp-proxy's cross-instance
+# duplicate-name detection then falls back to auto-generated tool names
+# for all of them ("Tool custom name 'list-customers' already exists in
+# both plugin X and Y") — found and reverted 2026-08-23, see STATUS.md.
+# ai-mcp-proxy already tolerates a route with multiple methods (logs a
+# harmless "skips method selection" notice, same as catalog-mcp's existing
+# POST+DELETE route already does) — extending to GET here is the same
+# class of thing, not new risk.
 apiVersion: configuration.konghq.com/v1alpha1
 kind: KongRoute
 metadata:
@@ -12,6 +25,7 @@ spec:
   hosts:
     - ${REST_HOSTNAME}
   methods:
+    - GET
     - POST
     - DELETE
   paths:
@@ -19,24 +33,3 @@ spec:
   strip_path: false
   tags:
     - customers
----
-apiVersion: configuration.konghq.com/v1alpha1
-kind: KongRoute
-metadata:
-  name: ${NAME}-customers-mcp-stream
-  namespace: ${NAMESPACE}
-spec:
-  serviceRef:
-    type: namespacedRef
-    namespacedRef:
-      name: ${NAME}-customers-mcp
-  name: customers-mcp-stream
-  hosts:
-    - ${REST_HOSTNAME}
-  methods:
-    - GET
-  paths:
-    - /customers-mcp
-  strip_path: false
-  tags:
-    - customers