A small bowl of sauce can change how a dish tastes, but “Thai dipping sauce” is not a single recipe. Restaurants may prepare their own versions or buy prepared products. If you are reading a menu, the sauce name gives you a starting point, not a complete ingredient list. If you run a restaurant, describe what is actually served with each dish.
Three names you may see
Nam chim kai is often translated as sweet chilli sauce. A Thailand Foundation article gives one preparation using vinegar, sugar, chilli and garlic, and notes that the sauce is served with more than chicken. Prik nam pla, also called nam pla prik, is a fish-sauce-and-chilli condiment. Nam jim jaew is another dipping sauce that may accompany grilled food; the Foundation's fish-sauce guide discusses both. These examples identify styles, not mandatory recipes.
Match the sauce to the dish actually served
One restaurant may bring a sauce automatically; another may offer it only on request. State whether a dish comes with a separate dip, a sauce already mixed in, or a choice of sauces. A photo should show the portion and bowl customers will normally receive. If a sauce is optional or costs extra, say so beside the dish rather than hiding the detail in a general note.
Check ingredients before dietary labels
Do not infer that a sauce is vegetarian, free of fish, or safe for a particular allergy from its colour or English name. Fish sauce is an obvious example to verify, but packaged sauces and house recipes also vary. Check the current recipe, ingredient labels and kitchen handling before answering a guest. When the kitchen cannot confirm, say that clearly instead of promising a safe substitution. This article is not a substitute for the restaurant's current ingredient information.
A short menu-description template
Write “Served with [the restaurant's sauce name]: [main taste and ingredients confirmed by the kitchen].” Add “on the side” when customers can choose how much to use. Keep spice wording tied to your own sauce, since chilli levels can differ. Review the Thai, English and Chinese descriptions together whenever the supplier or recipe changes. For the main dish, a clear multilingual menu should explain the food as well as translate its name.