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Get tags: GET http://teamcity:8111/httpAuth/app/rest/builds/<buildLocator>/tags/
Replace tags: PUT http://teamcity:8111/httpAuth/app/rest/builds/<buildLocator>/tags/
(put the same XML of JSON or JSON as returned by GET)
Add tags: POST http://teamcity:8111/httpAuth/app/rest/builds/<buildLocator>/tags/
(post the same XML of or JSON as returned by GET or just a plain-text tag name)
(<buildLocator>
here should match a single build only)
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