Providing user confidence information to third-party systems

An online services system includes a mechanism for providing user confidence information to an external data consumer, and for determining user contribution quality. Using stored information about user actions and interactions, user confidence is evaluated for one or more parameters associated with the validity of the user's account and/or quality of the user's contributions to the online services system. Confidence values are assigned to each parameter, and the values are exposed to external data consumers. Using stored information, user actions and interactions are correlated with contribution quality to produce a metric indicative of user contribution quality. Users with low quality parameter metrics may have their contributions shown to a smaller audience or have a lower prominence in a news feed.