In a large pot of boiling salted water, cook pasta until al dente, according to package instructions. Drain; return pasta to pot.
Meanwhile, season shrimp with salt and pepper. In a large nonstick skillet, heat 2 teaspoons oil over high heat. Add half the shrimp; cook until lightly browned on both sides and opaque throughout, 3 to 5 minutes. Transfer to a plate; repeat with remaining oil and shrimp (reduce heat if browning too quickly).
Reduce heat to medium; add capers, red-pepper flakes, and tomatoes. Cook, stirring occasionally, until tomatoes have softened and sauce has thickened, 10 to 15 minutes. Season with salt and pepper. Add sauce and shrimp to pasta; toss.