Source credibility assessment examines expertise, editorial standards, transparency, evidence quality, corrections, conflicts of interest, publication date, and whether a source is primary or merely repeats another claim. Professional design and confident language do not establish authority by themselves.
Credibility is contextual rather than a permanent score for an entire domain. A reliable publisher can make mistakes, and a less familiar source can provide strong primary evidence, so assessment should connect each claim to the specific document and evidence that supports it.