What was the intended purpose of the federalist papers?

The complete purpose of the Federalist Essays was to obtain public assistance for the then proposed constitution and to demonstrate their station and to influence the opinion of the reader.

The Federalist Papers are a series of 85 articles, which gave assistance to the Constitution of the United States. These 85 articles were drafted by  John Jay, Alexander Hamilton, and James Madison under the pen name "Publius". These articles act as the description of the newly proposed laws under the constitution to the people of U.S, in the hope of encouraging them to sanction the new constitution in the upcoming convention. These papers are considered as the most important source for translating and understanding the original purpose of the Constitution.

it foreshadows the theme of the paragraph and hints the topic that will be discussed in the paragraph!