Choreographies have been proposed as decentralized and scalable solutions for composing web services. Nevertheless, inherent characteristics of SOA such as dynamicity, adaptiveness and governance issues make the automated testing of choreographies difficult. The goal of our research is to adapt the automated testing techniques used by the Agile Software Development community to the SOA context. To achieve that, we aim to develop software tools and a methodology to enable TDD (Test-Driven Development) of web service choreographies. In this paper, we present our first steps in that direction, a software prototype composed of ad hoc automated test case scripts for testing a choreography. Based on qualitative and quantitative assessments performed on our prototype, we derived the requirements and challenges for developing an automated testing framework for supporting TDD of web service choreographies.