Preheat the oven to 400ºF. Line a large baking sheet with parchment paper. In a large bowl, combine the zucchini, yellow squash, bell pepper, onion, olive oil, and a generous pinch of salt and pepper. Toss to coat. Spread out on the baking sheet in an even layer. Roast for 20-25 minutes until tender and brown in spots. Set aside.

Bring a large pot of salted water to a boil. Add the pasta and cook according to package directions. Drain, rinse with cold water, and drain again. Transfer to a large bowl. Add the roasted vegetables, tomatoes, and pesto. Stir gently to combine. Stir in the artichoke hearts. Season to taste with salt and pepper. Serve at room temperature or chilled.