besides from that, the way to list the build tools would be:

build-tools-25.0.0

To recap:

android:
  components:
    - tools
    - platform-tools
    - tools
    - build-tools-25.0.0
    - android-25

There's some more information available at travis-ci/travis-ci#6040 (comment)

Thanks @MariadeAnton! I have finally have Travis running on API 25. 👍

Since this has not been fixed, just using command line:

install:
  - echo y | android update sdk -u -a -t tools
  - echo y | android update sdk -u -a -t platform-tools
  - echo y | android update sdk -u -a -t build-tools-25.0.2
  - echo y | android update sdk -u -a -t android-25
  - echo y | android update sdk -u -a -t extra-google-m2repository
  - echo y | android update sdk -u -a -t extra-android-m2repository

Thanks for contributing to this issue. As it has been 90 days since the last activity, we are automatically closing the issue. This is often because the request was already solved in some way and it just wasn't updated or it's no longer applicable. If that's not the case, please do feel free to either reopen this issue or open a new one. We'll gladly take a look again! You can read more here: https://blog.travis-ci.com/2018-03-09-closing-old-issues