5. A system comprising: one or more computers; and a computer-readable medium coupled to the one or more computers having instructions stored thereon which, when executed by the one or more computers, cause the one or more computers to perform operations comprising: receiving a search query input and identification of a context file from a third-party content provider, wherein the third-party content provider is configured to receive the search query input from a client device and is configured to determine the identification of the context file based on the search query inputs; processing the context file to identify one or more commands for processing the search query input and one or more commands for processing search results wherein one or more of the commands for processing the search query input each specifies a respective precondition for evaluation of another of the commands for processing the search query input; processing the search query input according to the one or more commands for processing the search query input to produce one or more context processed search queries; obtaining a plurality of search results responsive to the context processed search queries; processing the search results according to the one or more commands for processing search results to produce a plurality of context processed search results; analyzing, for each of one or more of the context processed search results, whether a corresponding entry in an annotation file refers to spam; and removing from the plurality of context processed search results one or more of the context processed search results that each have a corresponding entry in the annotation file that refers to spam to create a plurality of modified search results; and providing the modified search results to the client device.
5. A system comprising: one or more computers; and a computer-readable medium coupled to the one or more computers having instructions stored thereon which, when executed by the one or more computers, cause the one or more computers to perform operations comprising: receiving a search query input and identification of a context file from a third-party content provider, wherein the third-party content provider is configured to receive the search query input from a client device and is configured to determine the identification of the context file based on the search query inputs; processing the context file to identify one or more commands for processing the search query input and one or more commands for processing search results wherein one or more of the commands for processing the search query input each specifies a respective precondition for evaluation of another of the commands for processing the search query input; processing the search query input according to the one or more commands for processing the search query input to produce one or more context processed search queries; obtaining a plurality of search results responsive to the context processed search queries; processing the search results according to the one or more commands for processing search results to produce a plurality of context processed search results; analyzing, for each of one or more of the context processed search results, whether a corresponding entry in an annotation file refers to spam; and removing from the plurality of context processed search results one or more of the context processed search results that each have a corresponding entry in the annotation file that refers to spam to create a plurality of modified search results; and providing the modified search results to the client device. 6. The system of claim 5 , wherein the context file refers to one or more related context files, and wherein processing the search query input according to the one or more commands for processing the search query input further comprises; processing the search query input according to one or more additional commands for processing the search query input in the one or more related context files.