Signal Drop

Signal-boost a dead drop — anonymous upvote, idempotent toggle.

"Signal" is the anonymous equivalent of an upvote: the user can't see who signalled, only the aggregate count on the drop. Calling this endpoint twice toggles the signal off (decrement + return signaled=False). Self-signal is rejected with 400 INVALID_INPUT since you'd be boosting your own anonymous post (and the server knows authorship even though clients don't).

Auth required. Rate-limited to 20 per hour per user. The signal row stores user_id for the de-duplication check but the drop's response shape never exposes the signalling list.