The service has to accept the request again
Hundreds of business tasks have taught me how easily an agent can solve the problem next to the real one. A composite example makes the risk clear. After an update, a service runs on the developer's computer while the request still fails in the test environment. If I ask an agent to "sort out the configuration," it may tidy the files without fixing the request.
In that scenario, I would state the outcome differently. The service accepts the request in the test environment. The old connection format still works, and the error does not return. Now the place to check is obvious. A file change is only one step.
I would give the agent the error message, the working configuration, and one constraint: keep the old connection format working. It can look up anything else if the task calls for it.
Someone else checks the consequence
I would have a second agent check this composite scenario. It would open the test address and send the same request. The author expects success; a fresh pair of eyes is more likely to notice the mismatch.
That one check is enough. While the request still fails where the service will be used, a tidy file on a developer's computer has not solved the task.
How that experience shapes Arcanada
Arcanada is where I keep my long-running work with agents together. I began building it because two large ambitions had to coexist with paid work and supporting my family. Here the original request stays beside the change, which helps me catch a mismatch before I accept the result.
Whenever a change looks tidy, I ask one last question: does the service accept the right request where people will use it? If the request still fails, the task is not finished.