Update README.rst to more accurately reflect the scope of the project

README.rst

@@ -10,31 +10,40 @@ Course Discovery Service  |Travis|_ |Coveralls|_
 .. |Codecov| image:: http://codecov.io/github/edx/course-discovery/coverage.svg?branch=master
 .. _Codecov: http://codecov.io/github/edx/course-discovery?branch=master
 
-The ``README.rst`` file should start with a brief description of the repository,
-which sets it in the context of other repositories under the ``edx``
-organization. It should make clear where this fits in to the overall edX
-codebase.
+The Course Discovery API an data aggregator with several purposes:
 
-Overview (please modify)
-------------------------
+1. Allow external parties to access data about Courses in an OpenEdX installation
+   from a single central location (no matter which the system of record for that
+   data is), in a way that can be secured and will not have operational impact
+   on the running OpenEdX installation.
+2. Allow other services inside an OpenEdX installation to consume a consolidated
+   source of course content for presentation to users (for instance, for
+   the purposes of course marketing and discoverability).
+3. Provide a facility for naming dynamic groups of courses (catalogs) for
+   use by other services in the system (such as coupon fulfillment and external
+   course discovery filtering).
 
-The ``README.rst`` file should then provide an overview of the code in this
-repository, including the main components and useful entry points for starting
-to understand the code in more detail.
+To aid in these goals, the Course Discovery Service will collect data from
+several systems internal to the OpenEdX installation. Initially, this will
+just be Otto (the Ecommerce service), and in the future will it will also include
+Studio, and in the edX.org implementation, our Drupal marketing site. The design
+intention is that additional systems should be cheap to add to the same framework.
 
+Overview
+--------
 
-Documentation (please modify)
------------------------------
+As a standard django application :module:`course_discovery.views` is a useful
+entry point, as it defines the APIs that this service will support.
 
-The ``README.rst`` should include a link to the developer documentation. This documentation should be hosted on
-Read the Docs. An example statement and link are below.
+Documentation
+-------------
 
-The docs for Course Discovery Service are on Read the Docs:  https://open-edx-course-discovery.readthedocs.org.
+The docs for Course Discovery Service will be on Read the Docs:  https://open-edx-course-discovery.readthedocs.org.
 
 License
 -------
 
-The code in this repository is licensed under LICENSE_TYPE unless
+The code in this repository is licensed under AGPL unless
 otherwise noted.
 
 Please see ``LICENSE.txt`` for details.