Loops Subscriber Agent
Handles every Loops unsubscribe, bounce and new contact the moment it fires: suppression checked first, the facts written onto the contact, and Slack pinged only for a customer domain going dead or a run of unsubscribes off one send.
On a Loops audience the contacts are usually your own users, which makes an unsubscribe and a bounce two completely different pieces of news. This agent picks up each audience event as it fires, checks suppression before doing anything at all, records what happened on the contact, and interrupts you only when the event carries weight: a customer domain that stopped accepting mail, or a run of departures off one send. There is no send tool and no delete, so the worst it can manage is a property you change back.
## What people use it for
- **A bounce that costs money** - Billing mail bouncing at a customer domain is a revenue problem wearing a deliverability costume. It reaches Slack with the plan, the renewal date, and who else at that domain still gets mail.
- **Departures you can read later** - Each one is recorded on the contact with the send and the list behind it, so a pattern following one email is visible in the audience instead of living inside a notification you scrolled past.
- **Suppression checked, never undone** - The first move on any event is reading the suppression state, and lifting one is not something it can do. Consent stays exactly where the person put it.
- **Quiet unless it matters** - Across a few thousand contacts most events are ordinary and get handled without a word. What reaches the channel is the customer domain and the unsubscribe run, which on a list this size is a few messages a month.
## Before you fork
**What has to be in place before it runs?**
A Loops API key able to read and update contacts and read suppressions, plus the Slack channel for signals worth interrupting. Then you write the audience rules: which property records each kind of event, which domains and plans deserve a ping, and the number of departures from a single send that you would call a run. Nothing at all happens until an event fires.
**Can it email a contact or remove one?**
No to both. There is no sending tool wired in, which means no contact ever receives anything from this agent, and deleting somebody, unsuppressing an address or shifting a person between mailing lists all sit outside what it can do. It writes the properties your rules name and it posts to Slack, and either of those you can reverse yourself in a minute.
**Is this overkill for three thousand contacts?**
That is roughly the size it was built for. Large list tooling thinks in bounce rates and cohorts, which is the wrong lens when a single address belongs to a customer you could name from memory. Cost follows events rather than how many contacts you hold, so a quiet week amounts to a few short runs, and a big announcement costs one run per departure it produces.
