At the vast majority of Austin restaurants, food determines the rating outright.

But occasionally service and ambience can tip the scales in favor of an extra star.

That's what happened recently with Carmelo's Ristorante Italiano, the classic Italian spot that has become a mainstay of downtown dining.

The dishes were high three-star, but the service and atmosphere pushed the overall experience up a notch.

Service, in particular, showed a significant improvement over my last review.

Not only were the waiters exceptionally attentive, but they carried out several deft touches. At a distance, they polished plates and silverware before bringing them to the table, eliminating unsightly smudges. After pouring the water, a server returned with a bowl of sliced lemons to ask if we would like some in the water.

In a further effort to make the restaurant feel special, Carmelo's is serving a complimentary starter (as only a few top restaurants do): a plate with several small, tasty meatballs in tomato sauce.

Also, the basket of warm bread was served with a noticeably higher grade of olive oil than many restaurants are using.

All of that is in keeping with the classy ambience offered by the historic setting, a stone structure built at a hotel in the 1870s that immediately sets the place apart on approach. (There is also free valet parking, an important perk in downtown Austin.)

Inside, the lights were soft, an accordion player provided the background music and an alluring arrangement of desserts near the entrance set the tone for the upcoming meal.

One appetizer featured an artichoke bottom ($12) mounded with lump crab meat that was mixed with a few almonds (providing a textural contrast with the tasty crab) and served piping hot.

The mussels and clams ($11) were served with a spicy marinara sauce -- one of three options, along with a cream sauce and mild tomato sauce -- that gave a zesty thrust to the tender shellfish.

In the pollo ricotta Marsala ($21), a boneless chicken breast was stuffed with ricotta and prosciutto, sliced in medallions and served with a Marsala wine sauce over a bed of fusilli with colorful mixed vegetables at each end of the oval plate. The chicken was an appealing union of flavors, with the slightly sweet sauce offset by the salty proscuitto of the filling.

The veal piccata ($21) featured thin slices of scaloppine that were sauteed with lemon juice and capers in a tasty and tender version of one of the most traditional Italian dishes. The meat was accompanied by roasted potatoes and mixed vegetables.

For dessert, a three-tiered pastry cart -- filled with luscious-looking confections -- was wheeled to the table for diners' scrutiny.

The crème brûlée cheesecake ($6.50) was rich and creamy (although we failed to detect the pronounced caramel flavor that we assumed gave it its name).

The wonderful toscanella ($6.50) was made with a pastry crust, rounded on the ends, that was filled with a thick, sweetened cream flavored with vanilla and Grand Marnier and topped with shaved chocolate.

That lovely ending was in key with everything that had come before. Throughout the last course, a server returned with a silver coffee pot to refill our cups each time the contents diminished by half. His actions emphasized that Carmelo's isn't just about food. It values the full experience.