The remaining paragraphs of Article 5 are very important and can differ with each treaty.
For instance, in the treaty with Bangladesh, paragraphs 3 and 4 expand on what will, and will not be considered to be a PE. Details such as a warehouse for storage will not be considered to be a PE but an employee with the ability to sign contracts will likely cause the business to have a PE.
There is often also a paragraph excluding a business from having a PE simply because they have an agent in the country. Another standard exclusion ensures that owning a subsidiary located in the other country will not cause you to have a PE.
You always need to look at this article for ‘special’ circumstances. Such as the Canada-US treaty which includes a rule on services where an individual is in the other country for more than 183 days or the Canada-Barbados treaty which includes rules on insurance risks and premiums.