who is the script writer?
Greg Daniels and Michael Schur.
Parks and Recreation (season 1)
Daniels and Schur wrote the script for the pilot episode in mid-2008. 
what's the genre of parks and recreation (season 1)? Comedy. which are the main characters? Amy Poehler, Rashida Jones, Paul Schneider, Aziz Ansari, Nick Offerman, and Aubrey Plaza.
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Parks and Recreation (season 1) [SEP] Writing
The original script portrayed Leslie and Mark as slightly less likable than they appeared in the final draft. For example, in the premiere episode, Mark asks Ron to greenlight the park because he is inspired by Leslie's optimism and wants to help her. In the original script, Mark intervened because he was attracted to Ann and wanted an excuse to keep seeing her. The characters were made more likable in response to feedback the episode received from focus groups and press tour screenings. The first-season episodes were written and developed relatively quickly after each other, and Schur said the staff was treating the entire six-episode season as if it was one television pilot.