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Answers "can I onboard another connection right now?" before you take the order. Everything is scoped to the token's workspace — there is no way to ask about another one. `slots.available` is what `POST /connections` can still consume with an active licence; `slots.nextExpiry` is the date you must renew before, so a slot never expires underneath a customer who already paid. `connections.needsReconnect` counts numbers waiting for their owner to scan a fresh QR (the same state that fires the `connection.disconnected` webhook). **A slot is capacity, not a phone number** and not something you bind to a customer: it attaches when a number actually pairs, and deleting a connection returns its slot to the pool carrying whatever time is left on it, ready for the next number you connect. Map WASync's connection `id` (a stable cuid, echoed by every REST response and by `connection_id` on every webhook) to your own customer record — we mint the id, you map it. Do not try to track slots per customer; track connections.