Hi @mehm8128. Looking through your example, I see that you create the transport on every render. connect-query now takes into account the transport when generating keys so that's likely where it's breaking. There are a few ways to fix this:

1. Move the transport creation to the module level.

const baseTransport: ConnectTransportOptions = {
  baseUrl: "/api",
  useBinaryFormat: false,
};
const transport = createConnectTransport(baseTransport)
export const useGrpcClient = () => {
  ...

2. Add a special key to the transport so it can be serialized as a key.

const transport = addStaticKeyToTransport(createConnectTransport(baseTransport), 'grpc-transport'));

Generally, I'd recommend the option 1, since there's no magic string, but it depends on if your transport needs some runtime data. In this example, I don't see anything that would indicate it needed access to runtime data so this is the best option. Option 2 on the other hand, can be used to define exactly what you want to key to be. This means that if you want to trigger queries when something about the transport changes, you need to make sure that grpc-transport string changes along with it (doesn't matter what it is, as long as it changes).

Thank you so much!!!
Because my product uses runtime data to create transport unlike repro code, I decided to choose the second option at this time and it works well without occurring infinite loop!
I'll close this issue as solved 😄

I realized there's another option if the static key method is a little restrictive: You can memoize the transport using useMemo from react. Depends on the use case really. addStaticKeyToTransport works for SSR as well where useMemo does not. Glad it worked though.