No, they did not. The Articles are not that long a document, and you can read them here pretty quickly. You will notice that they go into the most detail about waging war together, and that was the purpose: they were written when the states found themselves at war with Britain, and they needed an agreement about how that was to be done. So, cooperation, friendship, no states making war without the agreement of all the United States.

But that friendship and cooperation did not apply to places that were not yet states. Vermont was one of these, and claimed by three states: New Hampshire, New York , and Massachusetts. This became a real muddle after the French and Indian War. When the French lost control of the area, in 1764 what's now Vermont was given to New York- despite the fact that New Hampshire had already laid claim to much of it and even founded towns. Residents who thought themselves part of New Hampshire were informed that they needed to pay taxes to New York. This created resentment. By 1770, it was armed resentment, by Ethan Allen and the Green Mountain Boys, but though Vermont residents would write a constitution in the same year the Articles of Confederation were written, in 1777, Vermont was not included in the United States:

The dispute was ignored during the Revolutionary War, but came back immediately afterwards. During the Articles of Confederation period, Vermont's petitions to join the United States were blocked by New Hampshire and New York. Some Vermonters made noises about extending their turf to the east bank of the Hudson, and George Clinton, the governor of New York, assiduously tried to enforce New York claims. In 1784 there was some military gesturing and militia-mustering-and-marching that some have called a Border War, but it really never rose to the level of bloody destructive conflict. After negotiations finally in 1791 Vermont joined the new United States under the constitution.

EDIT: There were a number of disputes in the colonial period emanating from the British practice of granting territory for new states without knowing anything about the geography, or doing a preliminary survey. The 17th c. saw border conflict between Pennsylvania and Maryland, Maryland and Virginia, Pennsylvania and Delaware. There were many more that had to be resolved over claims on the new territories, following the Revolutionary War, not just that between Vermont and New York. Many were settled under the Articles.. You can see a map here . Some important acts by the Continental Congress under the Articles period specified how new territories were to be surveyed and how new states were to be created from it and admitted, so border disputes between the new states became much more manageable.