Place the whole-wheat spaghetti in a large saucepan and add the water so the pasta is submerged.
Add the halved or quartered cherry tomatoes, sliced pitted olives, rinsed capers, anchovy fillets, minced garlic, minced parsley, olive oil, salt, and freshly cracked black pepper to the pan.
Cover the pan and bring to a medium heat, then cook uncovered or partially covered as needed to keep the spaghetti mostly submerged and stir gently occasionally to prevent sticking.
Cook for about 13–15 minutes, stirring once or twice, until the spaghetti is al dente and the sauce has thickened and reduced.
Taste and adjust seasoning if needed, then serve immediately to preserve the pasta's al dente texture.
