Issues with Github/Context7 sample MCPRoute

[rajakumar17]

I am trying out Envoy AIGW with minikube setup. I followed the prerequisites, installation and basic usage instructions and was able to verify chat completion api.

However, the Basic MCPRoute sample failed to work. I tried with both github and Context7 mcp server backends.

The following are the config for context7 mcp

apiVersion: aigateway.envoyproxy.io/v1alpha1
kind: MCPRoute
metadata:
  name: mcp-route
  namespace: default
spec:
  parentRefs:
    - name: envoy-ai-gateway-basic
      kind: Gateway
      group: gateway.networking.k8s.io
  path: "/mcp-c7" # Clients connect to http://gateway-address/mcp
  backendRefs:
    - name: context7
      kind: Backend
      group: gateway.envoyproxy.io
      path: "/mcp"
---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: Backend
metadata:
  name: context7
  namespace: default
spec:
  endpoints:
    - fqdn:
        hostname: mcp.context7.com
        port: 443
---

Invoking using postman mcp client, gave me the following errors in the envoy proxy

Note

envoy {":authority":"localhost","bytes_received":193,"bytes_sent":167,"connection_termination_details":null,"downstream_local_address":"10.1.0.39:10080","downstream_remote_address":"192.168.65.3:61900","duration":0,"method":"POST","protocol":"HTTP/1.1","requested_server_name":null,"response_code":503,"response_code_details":"upstream_reset_before_response_started{remote_connection_failure|delayed_connect_error:_Connection_refused}","response_flags":"UF","route_name":"httproute/default/ai-eg-mcp-main-mcp-route/rule/0/match/0/*","start_time":"2026-02-11T08:42:28.980Z", "upstream_cluster": "httproute/default/ai-eg-mcp-main-mcp-route/rule/0", "upstream_host":"127.0.0.1:9856", "upstream_local_address":null, "upstream_transport_failure_reason":"delayed_connect_error:_Connection_refused","user-agent":"PostmanClient/11.81.3 (AppId=042fb535-814d-4ade-8a35-a6c49ba6bf85)"," x-envoy-origin-path":"/mcp-c7","x-envoy-upstream-service-time":null,"x-forwarded-for":"192.168.65.3","x-request-id":"89d97a60-af1c-408c-8cda-19ffefb459cf"}

I am clueless on what I am missing, which causes the 503 error. Any help will be greatly appreciated.

[Dericko681]

Hi @rajakumar17 Did u intentionally add the -c7 to the path in

spec:
  parentRefs:
    - name: envoy-ai-gateway-basic
      kind: Gateway
      group: gateway.networking.k8s.io
  path: "/mcp-c7"

?

[rajakumar17]

Yes, I did as I had another mcp route configured for github separately

[Dericko681]

i'm not sure we sync understanding
if u are still facing this issue can u remove the -c7 and test with just /mcp? i'm not sure that is where to specify diff mcp routes

[rajakumar17]

Changed it to mcp, still the same error.

[rajakumar17]

Not able to understand what this "upstream_host":"127.0.0.1:9856" points to?

[Dericko681]

It seems you are facing some upstream issues with envoy. Envoy is routing to "upstream_host":"127.0.0.1:9856" meanwhile your upstream host is set to mcp.context7.com

I am running your setup with the BackendTLSPolicy below and it works, testing with the npx inspector for mcp

apiVersion: gateway.networking.k8s.io/v1
kind: BackendTLSPolicy
metadata:
  name: context7-tls
  namespace: converse-llm
spec:
  targetRefs:
    - group: gateway.envoyproxy.io
      kind: Backend
      name: context7
  validation:
    wellKnownCACertificates: "System"
    hostname: mcp.context7.com

Redo it in a clean cluster,
If you are still facing this issue pls document a clear way to duplicate this
thanks