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APIs
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The TOOLS4CITIES front-end applications such as CITYlayers, Workflow Launcher, and RETROfitter can run Workflows by connecting to the APIs of CITYtwin.
These APIs provide web end-points for requesting information or running simulations / calculations by providing them data.
Currently, CITYtwin consists of the following APIs

.. toctree::
   :maxdepth: 1
   :caption: Contents

   hubapi/index
   abcacceleratorapi/index