Techniques are described for providing information about a current state that is modeled with multiple state attributes. In some situations, the providing of information includes receiving from first and second sources indications of ability to supply values for, respectively, an indicated one of the state attributes and another of the state attributes. In such situations, after receiving an indication of the indicated attribute from a first client, the providing of information further includes determining that the first source is available to supply a value for the indicated attribute, obtaining from the first source an indication of the value and information describing the indicated value, determining based at least in part on the descriptive information whether the indicated value is appropriate to be supplied to the client, and supplying the indicated value to the client when it is determined that the indicated value is appropriate.