Channel tags "must be an array of non-empty strings."

[b1conrad]

Perhaps we could relax this a bit, by converting a singleton into an array containing it, on the one hand, and the values in an array into strings on the other hand?

[b1conrad]

Rationale would be to avoid the error case, which interrupts whatever flow was going on. A developer can always see that the newly created channel has unexpected tags, and fix the problem at her convenience. Perhaps an empty array could become a single "none" tag.