anchor.diff:  
   - the first time an item is added to ImpactStory (through the [web interface](http://impactstory.org), the javascript embed code, or the REST api)
   - while-you-wait when someone clicks the "update" button on the web interface
  -- regularly, behind-the-scenes, for **sponsored items**
  -
  -With an api key you can "sponsor" various items to keep them up-to-date with fresh metrics.  
  +- regularly, behind-the-scenes, for **active items**
  +
  +With an api key you can **activate** items to keep them up-to-date with fresh metrics.  
   These fresh metrics are made openly available to anyone who requests metrics for that item.
   Open dissemination for the win!
   
  -We only guarantee an item requested through the API will have fresh metrics if that item has been sponsored.
  -Items are sponsored by adding them to the ImpactStory database through a [POST /item](#post_item) API call.
  -
  -Up to 1000 items can be sponsored for free by each API key.  Sponsoring more than 1000 items will have an annual fee to provide sustainability for our nonprofit service.
  +We only guarantee an item requested through the API will have fresh metrics if that item has been activated.
  +
  +Items are activated by adding them to the ImpactStory database through a [POST /item](#post_item) API call.
  +
  +Up to 1000 items can be activated for free by each API key.  Activating more than 1000 items will have an annual fee to provide sustainability for our nonprofit service (waivers available in some cases).
   
   To request an ImpactStory API key, send an email to [team@impactstory.org](mailto:team@impactstory.org).
   
   ## rate limits
   
  -We do not impose rate limits at the moment, but we recommend delaying for a few seconds between each request.  It often takes us 5-10 seconds to collect metrics on an item, due to the latency of our external metrics providers.
  +We do not impose rate limits at the moment, but we recommend delaying for a few seconds between each request.  It often takes us 5-10 seconds to collect metrics on an item the first time, due to the latency of our external metrics providers.
   
   ## data licenses
   
   - All data in the ImpactStory API is released under as open a data licence as the primary data providers permit it to be.  We plan to inventory these licenses but haven't got an updated list at the moment, so please check with the primary data providers.
  +- Some providers allow us to show their metrics in our webapp but restrict its dissemination through our api.  Scopus citation data is available through our web application but not through the API.  CiteULike data is available through the API only in certain circumstances.
   - Native ImpactStory data in the API (if there is any?) is released under a [CC0 waiver](http://creativecommons.org/publicdomain/zero/1.0/).  
  -- Scopus citation data is available through our web application but not through the API.
   
   ## contact info
   
  
positive.code: [CORS](http://en.wikipedia.org/wiki/Cross-origin_resource_sharing) is enabled.
  
  
  ## keys, fresh metrics, and sponsored items
  
  ImpactStory gathers metrics on any type of scholarly object with a url (or doi, or pubmed id, or github id, ...).  Because we cover such a large span of scholarly resources (and do not yet have the resources of Google), we only gather metrics on items once they have been specifically requested.
  
  
negative.code: add an item
  <a id="post_item"></a>
  Add an item to the ImpactStory system using the given namespace and id.  
  Returns `201` even if the item is already in the database, because this call also registers the item as **active** under the supplied API Key (see top of this page for more information).
  
  After POSTing an item, the item data can be obtained through [GET /item](#get_item) calls.
  --
  