Get first paragraph (and only text) of a Wikipedia article returns not desired result

Question

I'm trying to retrieve the first paragraph of text for an article of Wikipedia, UNIX in this example, but it returns me a non-desired output.

For what I've been reading on the Wikipedia api and here on StackOverflow, this is the request URL to make the call:

http://en.wikipedia.org/w/api.php?format=php&action=query&titles=unix&redirects=1&prop=revisions&rvprop=content&rvsection=0&rvlimit=1

My expected output will be:

Unix (officially trademarked as UNIX, sometimes also written as Unix in small caps) is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, Michael Lesk and Joe Ossanna.[1] The Unix operating system was first developed in assembly language, but by 1973 had been almost entirely recoded in C, greatly facilitating its further development and porting to other hardware. Today's Unix system evolution is split into various branches, developed over time by AT&T as well as various commercial vendors, universities (such as University of California, Berkeley's BSD), and non-profit organizations.

My current result:

{{Use dmy dates|date=August 2012}}
{{Infobox OS
|name               = Unix
|logo               = 
|screenshot         = [[File:Unix history-simple.svg|250px]]
|caption            = Evolution of Unix and Unix-like systems
|website            = [http://www.unix.org unix.org]
|developer          = [[Ken Thompson (computer programmer)|Ken Thompson]], [[Dennis Ritchie]], [[Brian Kernighan]], [[Douglas McIlroy]], and [[Joe Ossanna]] at [[Bell Labs]]
|source_model       = Historically [[Closed source software|closed source]], now some Unix projects ([[Berkeley Software Distribution|BSD]] family and [[Illumos]]) are [[open source]]d.
|frequently_updated = yes <!-- Release version update? Don't edit this page, just click on the version number! -->
|programmed_in      = [[C (programming language)|C]] 
|kernel_type        = [[Monolithic Kernel|Monolithic]]
|ui                 = [[Command-line interface]] & [[Graphical user interface|Graphical]] ([[X Window System]])
|language           = English 
|family             = Unix
|released           = {{start date and age|df=yes|1969}}
|license            = [[Proprietary software|Proprietary]]
|working_state      = Current 
}}

'''Unix''' (officially trademarked as '''UNIX''', sometimes also written as '''<span style="font-variant: small-caps;">Unix</span>''' in small caps) is a [[Computer multitasking|multitasking]], [[multi-user]] computer [[operating system]] originally developed in 1969 by a group of [[American Telephone & Telegraph|AT&T]] employees at [[Bell Labs]], including [[Ken Thompson]], [[Dennis Ritchie]], [[Brian Kernighan]], [[Douglas McIlroy]], [[Michael Lesk]] and [[Joe Ossanna]].<ref name=" Ritchie">{{cite journal
  | last = Ritchie
  | first = D.M.
  | authorlink = 
  | coauthors = Thompson, K.
  | title = The UNIX Time-Sharing System
  | journal = Bell System Tech. J.
  | volume = 57
  | issue = 6
  | pages = 1905-1929
  | publisher = American Tel. & Tel.
  | location = USA
  | date = July 1978
  | url = http://www.alcatel-lucent.com/bstj/vol57-1978/articles/bstj57-6-1905.pdf
  | issn = 
  | doi = 
  | id = 
  | accessdate = December 9, 2012}}</ref>  The Unix operating system was first developed in [[assembly language]], but by 1973 had been almost entirely recoded in [[C (programming language)|C]], greatly facilitating its further development and [[Software portability|porting]] to other hardware. Today's Unix system evolution is split into various branches, developed over time by AT&T as well as various commercial vendors, universities (such as [[University of California, Berkeley]]'s [[BSD]]), and [[non-profit]] organizations.

[[The Open Group]], an industry standards consortium, owns the UNIX trademark. Only systems fully compliant with and certified according to the [[Single UNIX Specification]] are qualified to use the trademark; others might be called ''Unix system-like'' or ''[[Unix-like]]'', although the Open Group disapproves<ref>[http://www.unix.org/questions_answers/faq.html#7a  What is a "Unix-like" operating system?] Unix.org FAQ</ref> of this term.  However, the term ''Unix'' is often used informally to denote any operating system that closely resembles the trademarked system.

During the late 1970s and early 1980s, the influence of Unix in academic circles led to large-scale adoption of Unix (particularly of the [[Berkeley Software Distribution|BSD]] variant, originating from the [[University of California, Berkeley]]) by commercial startups, the most notable of which are [[Solaris (operating system)|Solaris]], [[HP-UX]], [[Sequent Computer Systems|Sequent]], and [[AIX operating system|AIX]], as well as [[Darwin (operating system)|Darwin]], which forms the core set of components upon which [[Apple Inc.|Apple]]'s [[OS X]], [[Apple TV]], and [[IOS (Apple)|iOS]] are based.<ref>{{cite web|url=http://marketshare.hitslink.com/operating-system-market-share.aspx?qprid=8&qpcustomd=0 |title=Operating system market share |publisher=Marketshare.hitslink.com |date= |accessdate=2012-08-22}}</ref><ref>{{cite web|url=http://developer.apple.com/library/mac/#documentation/MacOSX/Conceptual/OSX_Technology_Overview/SystemTechnology/SystemTechnology.html#//apple_ref/doc/uid/TP40001067-CH207-BCICAIFJ |title=Loading |publisher=Developer.apple.com |date= |accessdate=2012-08-22}}</ref> Today, in addition to certified Unix systems such as those already mentioned, [[Unix-like]] operating systems such as [[MINIX]], [[Linux]], and [[BSD]] descendants ([[FreeBSD]], [[NetBSD]], [[OpenBSD]], and [[DragonFly BSD]]) are commonly encountered. The term ''traditional Unix'' may be used to describe an operating system that has the characteristics of either [[Version 7 Unix]] or [[UNIX System V]]."

What is the correct way of retrieving an article?

Thanks in advance!

Answer 1

If you want plain text only, use TextExtracts: http://en.wikipedia.org/w/api.php?format=json&action=query&prop=extracts&explaintext=1&titles=Unix

This would produce: Unix is a multitasking, multi-user computer operating system that exists in many variants. The original Unix was developed at AT&T's Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. From the power user's or programmer's perspective, Unix systems are characterized by a modular design that is sometimes called the "Unix philosophy," meaning the OS provides a set of simple tools that each perform a limited, well-defined function, with a unified filesystem as the main means of communication and a shell scripting and command language to combine the tools to perform complex workflows.