The indefinite pronouns under investigation need to be classified separately, given that one (viz. ãge 'someone') consists of a synchronically indivisible form, while the other is generic-noun-based (ãgu/kwɔlki koyz 'something', composed of an indefinite quantifier and the generic noun koyz 'thing'). This bipartite system reflects the input provided by (modern) Standard Portuguese, in which the former special indefinite for inanimate referents algo 'something' is considered archaic and pragmatically highly marked, being substituted by the generic-noun-based construction alguma coisa (and also qualquer coisa) 'something'.
Source: Cardoso 2009: 232