according to Vinzent, Hegesippus invented the label "the Just" for James:
In his History of the Church from the beginning of the fourth century, Eusebius gives a few details about Hegesippus: H wrote in the seventies or eighties of the second century and was a convert from the Hebrews, probably of Samaritan background. Hegesippus, indeed, displays some considerable Samaritan knowledge, but combines it with a high esteem for the Jewish origins of the churches, especially the ones from Jerusalem. But he is equally bold in criticizing Judaic Pharisaism and Sadduceism, and also Samaritan Christianity. Moreover, he sees Samaritan Christianity as paving the way for Marcion’s teaching and the separation between Judaism and Christianity. To Hegesippus the parting of the ways between Judaism and Christianity was an inner-Hebrew dispute between a Pharisaic and a Pharisaic-Samaritan Christianity. In clear counter-position to Marcion, whose message he sees as a kind of Samaritan rejection of the Jews and their temple, Hegesippus reconnects the Church’s beginnings firmly with Jerusalem and the Temple, and roots the young community deeply in the wider family of Jesus and his brother James.
Against, but also partly aknowledging Marcion, Hegesippus paints James as ‘the Just’ who was announced by the prophets, carries all the Marcionite ascetic ideals (no wine, a vegetarian, no cutting of hair, no perfumes, no bathing) and makes people believe in the resurrection and judgement. He is portrayed like a Jewish-Christian alternative to the Pauline Marcion: Jesus’ earthly family counts against Paul’s visionary authority of the Risen Christ.
(Markus Vinzent, Christ’s resurrection in Early Christianity and the Making of the New Testament, Ashgate 2011, p.99-100, my bold)
But the only support for an anti-demiurgist origin of James is the fact that he was honoured by Naassenes, notoriously haters of YHWH