Director's loan agreement advice

For T1 Ent extension, 1 of the criteria stated as the director's loan agreement, is there a specific requirement on the agreement to make it legal? e.g. witnessed or stamped?
Appreciate advice on this.



(iii) you must provide a legal agreement, between yourself (in the name that appears on your
application) and the company showing:
(1) the terms of the loan,
(2) any interest that is payable,
(3) the period of the loan, and
(4) that the loan is unsecured and subordinated in favour of third-party creditors.

A loan agreement does not need a witness or stamp to be legal. That document is between you and your company and must have all the required information HO wants