Reply to a hand-off

Answer the customer. This is the only endpoint that sends something to one of your customers, so it behaves differently from the rest of the API.

Credential: API token · Role: owner, admin or responder (reply)

The reply leaves the building

It is not “add a message to a thread”. It goes out on the channel the conversation started on — back to WhatsApp, Messenger or Instagram, or by email from the connected mailbox — and is mirrored into the linked Slack thread and appended to the Zendesk or HubSpot ticket. If the customer is in the widget, it signals that a human has arrived.

Warning

Authorship comes from the token, never the body. The message is attributed to the token’s owner, and the name your customer sees is that teammate’s profile name. There is no way to reply as someone else, and the audit trail names who answered.

Note

Text only, and attachments are refused rather than dropped. The body takes 1–10,000 characters. Sending attachments is a 400, not a silent omission — attaching a file needs an authenticated upload into your workspace’s own storage, so it stays a dashboard flow.

Side effects worth knowing

Replying also stamps the first-reply time, and auto-assigns the hand-off to you if nobody owns it yet.

It emits handoff.message.created — and, with resolve: true, handoff.status.changed. If you wire both an API reply path and a webhook consumer, you will receive your own reply back as an event. Dedupe on the event id.