How a sequence works

A sequence is an automated journey. A contact enters on a trigger, then walks a graph of steps — send, wait, tag, stop — at their own pace. Two contacts who entered a week apart are at two different places in the same sequence.

Trigger and enrollment

One trigger per sequence, of two kinds: a contact joins a list, or a contact is given a tag. Once enrolled, a contact is in_progress until they reach the end (completed) or leave the road (stopped). Those two are not the same thing, and the screen counts them separately:
  • completed — the journey went all the way, or reached an explicit end step;
  • stopped — the contact unsubscribed or was suppressed, observed at the moment a step tried to send.
Declining the sequence's topic also takes the contact out: the remaining steps never go out.

The steps

StepWhat it does
Send an emailCarries its own subject and content — it does not point at a template
WaitHolds the contact for a delay before the next step
Add a tag / Remove a tagActs on the contact instead of writing to them
End the sequenceA planned ending, counted as completed
WebhookCalls a URL of yours as the contact passes

Draft and published version

A sequence is versioned. You edit a draft; publishing freezes it, and a published version never changes again. That is what makes an automation trustworthy: a contact who entered last month is walking the graph as it was when they entered. Only one version runs at a time. Publishing a new one applies it to contacts who enter afterwards. A sequence is active or paused. Pausing stops new entries and holds the journeys in place.
Pausing does not free a slot. The plan ceiling counts every sequence you own, paused ones included — there is no archive to put one on. Delete one to make room.

What refuses

Publishing is refused when the graph does not hold together, and the message names the steps at fault. Two cases are worth knowing in advance:
  • a step containing {{topicOptOutUrl}} while the sequence carries no topic — the link would render empty and reach the recipient dead;
  • removing the topic from a sequence whose published version still contains that shortcode. Open a draft, remove it, publish — or keep a topic.
Deleting a tag that a sequence triggers on, or that one of its steps sets, is refused too.

What it implies elsewhere

A sequence sends under the same rules as a campaign, against the same balance and the same refusal rules. Its emails need an unsubscribe link exactly as a campaign's do. The whole journey can be built without a screen — create, add steps, wire them, publish, activate — through the Sequences API.