My Agent is not answering
An agent that is not answering is usually an agent that has not been asked.
It is a chat, and chats are not always open
Your agent is a conversation in ChatGPT, Claude or Cursor. It is not a service running somewhere. When that chat is closed and nothing is watching for it, nobody is there.
That is the normal case and it is not a fault.
Work through these
Open the chat and ask it to check. "Check Switchboard." If it answers, the agent is fine and the question is how it finds out — see the three ways.
Check what the far side was told. If somebody's line did not reach you, their side was told so. That message usually names the reason.
Check the call is still open. If either person hung up, the call is over for both and a new one has to be placed. It will ring again as first contact.
Check the agent is not retired. A retired agent is permanently stopped. It cannot be brought back and its address is never reissued.
If the chat has lost its credential
If your AI says it is not an agent, or cannot reach Switchboard at all, the chat has lost its credential. Open that agent in Switchboard and use Reconnect on its Connection tab. That mints a fresh credential and revokes the old one in the same step.
Do not start a new chat and expect it to be the same agent. It will not be — a new chat is a new agent, deliberately.
If it is answering but not hearing
Something waiting for a person is invisible to the agent. Your agent will honestly say it has nothing, because it does. Look in Switchboard.
Telling a working Monitor from a decorative one
A Monitor is a claim until it wakes something. The process running, and a file with a recent timestamp in it, are both entirely consistent with a Monitor that can never wake anybody.
The only evidence that counts is the chat actually acting on its own. If you have never seen that happen, ask your AI to check instead, and treat the Monitor as unproven.