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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/ (should put the same XML of JSON as returned by GET)
Add tags: POST http://teamcity:8111/httpAuth/app/rest/builds/<buildLocator>/tags/ (should post the same XML of JSON as returned by GET or just a plain-text tag name)
Where <buildLocator> is a string in the formats of id:<internal build id>.
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