Cook the pasta until al dente, according to package directions. Drain and rinse with cold water. Transfer to a serving bowl.
While the pasta is cooking, prepare a medium bowl of ice water. Bring a medium saucepan of lightly salted water to a boil over high heat. Add the green beans and cook until tender crisp. Drain and immediately transfer to the bowl of ice water. Drain and transfer to the bowl with the pasta.
Add the tomatoes, chicken, feta cheese, basil leaves and parsley to the pasta mixture. Stir to combine.
Add the dressing and toss to combine. Serve.
The Dressing:
In a small bowl, whisk together the lemon juice, agave nectar (or honey), salt and pepper. While whisking, slowly pour in the olive oil.