An agent intermittently "loses" a tool. It reads a sensor fine ten times, then

flatly claims the value is unavailable — for a path you can see returning data in

the upstream server's own UI. Restart the session and it works again, for a

while. The cause isn't the tool and isn't the server: it's a raise_for_status()

in the HTTP client turning a perfectly normal 404 ("not published") into a