The Workers Party has said its presence in any future talks would make a difference to the outcome of political negotiations.
The party is fielding eight candidates in the assembly election on 26 November.
In its manifesto, the Workers Party said that if it succeeded in getting any candidates elected this would "provide a voice for socialists, democrats and anyone fed up with the failed policies of the past".
It said the Agreement needed a breath of fresh air, which it intended to provide through an open and transparent talks process.
The party manifesto called for an "all-out assault on sectarianism and racism", a stronger anti-poverty strategy and free personal care and travel for the elderly.
The Workers Party also said it was opposed to water charges, university fees and the trend towards a greater role for the private sector in the provision of public services.
The other main points of the Workers Party manifesto include:
Talks to be conducted between all parties elected to the assembly
Members of the assembly to be free to designate themselves as they wish
A major shake-up of the Civic Forum to mobilise civic society
Party general secretary John Lowry said: "The Agreement is in serious trouble. The Workers Party believe that the Agreement, despite all its flaws, still represents the best way forward for the people of Northern Ireland."