Service message is a specially formatted line of text in the build output which makes the
server
perform some
actions.
Here are just a few things you can do with their help:
If your reporting tool produces HTML reports, you can easily add a new tab to the Build Results page that will display the report.
REST API is another simple way you can interact with TeamCity.
Manage users, projects, builds or artifacts from your scripts, easily integrating TeamCity into your environment
Over 300 ready to use plugins are already available. If you still want to create a new one to make TeamCity even more powerful, use OpenAPI to implement it.
With Open API you can develop integration with version control systems, issue tracking systems, build tools, IDEs, notification programs and server health reports.