9. A system comprising: one or more processors; and memory storing one or more applications that, when executed on the one or more processors, perform an operation comprising: receiving, at a computing system via a network, a request from a user to retrieve information from the website; determining, via the computing system, that no satisfactory script for retrieving the requested information from the website exists in a database; receiving, at the computing system via the network, an indication of a page type for a first web page of the website from the user; retrieving, via the network, the first web page via a network; identifying, via the computing system, a candidate script element previously defined for the page type based on a second web page; determining, via the computing system, a candidate similarity score that measures a similarity between a part of the first web page and a part of a second web page, wherein the candidate script element is configured to perform a function on the part of the second web page; determining the candidate similarity score meets a predefined threshold; and performing, via the candidate script element, the function on the part of the first web page based on the determination that the candidate similarity score meets the predefined threshold.
9. A system comprising: one or more processors; and memory storing one or more applications that, when executed on the one or more processors, perform an operation comprising: receiving, at a computing system via a network, a request from a user to retrieve information from the website; determining, via the computing system, that no satisfactory script for retrieving the requested information from the website exists in a database; receiving, at the computing system via the network, an indication of a page type for a first web page of the website from the user; retrieving, via the network, the first web page via a network; identifying, via the computing system, a candidate script element previously defined for the page type based on a second web page; determining, via the computing system, a candidate similarity score that measures a similarity between a part of the first web page and a part of a second web page, wherein the candidate script element is configured to perform a function on the part of the second web page; determining the candidate similarity score meets a predefined threshold; and performing, via the candidate script element, the function on the part of the first web page based on the determination that the candidate similarity score meets the predefined threshold. 16. The system of claim 9 , further comprising: identifying, via the computing system, an alternative script element previously defined for the page type based on a third web page; determining, via the computing system, an alternative similarity score that measures a similarity between the part of the first web page and a part of a third web page, wherein the alternative script element is configured to perform the function on the part of the third web page; determining, via the computing system, that the candidate similarity score exceeds the alternative similarity score; and adding the candidate script element instead of the alternative script element to a script for retrieving the requested information based on the determination that the candidate similarity score exceeds the alternative similarity score.