The phrase "agreed foundation" is correct and usable in written English.
It can be used to refer to a mutually accepted basis or starting point for discussion, collaboration, or agreement.
Example: "Before we proceed with the project, we need to establish an agreed foundation that outlines our goals and responsibilities."
Alternatives: "mutually accepted basis" or "consensus foundation".
By Sunday we will have agreed the foundation of our manifesto, and a plan for national renewal that is equal to the scale of our challenge.
That regulation is fully justifiable when it mitigates the harm that some private actors might otherwise inflict on others ought to be the minimally agreed upon foundation for a larger conversation about the proper limits and potential pitfalls of specific kinds of government regulation.
President Donald Trump's personal charitable foundation agreed to shut down Tuesday amid an ongoing civil suit alleging Trump illegally used assets from the foundation to settle disputes in his businesses and boost his political campaign.
After seeing photographs of Mr. Alfonso, the foundation agreed to take on his case.
Dr. Barry Smith, director of the Dreyfus foundation, agreed that its primary goal was to explore the drug's usefulness.
In recent months, the two sides seemed to reach a tentative agreement in which the foundation agreed to pay the Port Authority about $50 million over many years.
Urban Partnership Bank, a new institution composed of several big Wall Street banks and a private foundation, agreed to assume ShoreBank's deposits and nearly all its assets.
The foundation agreed to lease the castle to the German government for 20 years, for a rent of one euro, and handed over the keys in 2007.
She said they could then be released, in colored collars, if a Bucharest resident or her foundation agreed to be legally responsible for them.
Soon after, Mrs. Clinton agreed to keep foundation matters separate from official business, including a pledge to "not participate personally and substantially in any particular matter that has a direct and predictable effect upon" the foundation without a waiver.
