Requests results in an alternative format
Values: atom, rss, json, json-in-script
Notes: Only used when alt=json-in-script
Define the ranking order for sorting queries
Values: relevancy, modification_time, name(type):value, 
Notes: The Ranking Language reference explains what you can do with this language and defines the language syntax.
Example: ...&orderby=price(float USD)
Limit repetitive results by placing a cap on similar items
Values: attribute, url, customerid, content, [expression]
The syntax is a comma-separated list of crowding criteria and maxvalue pairs: (i.e. &crowdby=crowding:maxvalue,crowding:maxvalue,...). The totalResults for the feed will still reflect the number of results that would have been available had crowding not been imposed.
Crowding criteria, read more
* Show each item's color a max of 2 times: ...&crowdby=color(text):2
* Show only 3 items originating from each url: ...&crowdby=url:3
Query results are returned in increasing or decreasing order.
Values: ascending, descending
Notes: If sortorder is specified but orderby is not, the results will be sorted by relevancy in the specified order.
Example: ...&orderby=price(float USD)&sortorder=ascending
Refines the query results
Values: true, false
The purpose of this mechanism is to restrict search results to items that reuse a certain number of attributes we consider to be essential for a given item type. This may improve the quality of certain search results, especially for queries that have many matching items.
On the other hand, setting refine=true might lead to items getting dropped that actually match the specified query. This is, in particular, bad for the customer-specific items feed, because it can give the impression that some attributes are missing, when in fact they simply do not meet the undocumented quality assumptions that this parameter introduces.
Because of this, refine=false by default. It should be enabled to improve quality of broad queries.
[item type: recipes][label:asian]
gets rewritten to:
[item type: recipes][cooking time][main ingredient][label:asian]