Can text messages and video call logs alone carry a genuineness assessment with little other evidence?

Generally, no — text messages and video call logs can be meaningful evidence of an ongoing relationship, but they are rarely enough on their own to carry a genuineness assessment without other corroborating evidence. IRCC looks at the whole file, and communication records, while useful for showing frequency and continuity of contact, do not by themselves show things like whether the relationship is known to family and friends, whether there is any financial interdependence, or whether the couple has made joint decisions or plans together.

Relying mainly on messages and calls is a common and avoidable weakness in weaker applications, not because that evidence is unimportant, but because it tends to leave gaps that other kinds of evidence would fill. Strengthening a file generally means adding categories like evidence of visits where they have happened, financial records showing any support or shared expenses, evidence that the relationship is known to both families and social circles, and anything showing joint decision-making about the future. Together with communication records, this kind of varied, corroborating evidence gives a much fuller and more convincing picture than messages alone ever could. If your current evidence leans heavily on texts and calls, it is worth reviewing the file with an immigration lawyer before applying to identify what other evidence you can realistically add.