What does the error message 404 Not Found mean when it says tcpSlaveAgentListener is invalid?

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The error message "404 Not Found" means that the requested resource or page could not be found on the server. In the case of "tcpSlaveAgentListener is invalid," this could indicate that the listener plugin for the Jenkins continuous integration tool is missing or not properly configured. This could result in the Jenkins slave agent failing to connect to the master, which could cause build failures or other issues with the CI/CD pipeline. Further investigation and troubleshooting are needed to resolve the issue.