Is the channel token a pairing code?

No. The token authenticates API requests. QR and pairing codes are used to approve a linked device on the phone.

Does logged_in mean connected?

No. They are separate fields. Read connected and state too, and check connected_stale when it is present.

Does a 515 mean pairing failed?

The post-pair 515 asks the linked device to reconnect to complete login. The service handles that reconnect.

Can I link again after unlinking on the phone?

Yes. Request a new QR or pairing code and approve it on the phone. Automatic paths do not create a new pairing for you.

Guides

How WhatsApp linked devices work for APIs

HelloHop links your WhatsApp number as a companion device, like WhatsApp Web. You approve pairing on your phone, then your application uses a channel token to call the API. The linked session carries messages and events. A dropped connection and a phone-side logout are different states and need different recovery actions.

Facts (as of October 2026, API v1)

The console offers QR pairing and a pairing-code option.
GET /v1/sessions/{channel} reports connected, logged_in and state separately.
Post-pair stream code 515 requests a reconnect to complete login; it is not itself a failed pairing.
After a phone-side unlink, you can link again by QR or pairing code.

Pairing connects your phone account to a channel

Open the channel in the console and request a QR code or pairing code. Approve the link on the phone that owns the WhatsApp number. Pairing creates a linked device; the channel token authenticates your application to the REST API. Keep these roles separate when diagnosing a failed request.

Read connection state

curl

API=https://api.hellohop.app/v1
BASE="$API/sessions/$CHANNEL_ID"
AUTH="Authorization: Bearer $CHANNEL_TOKEN"

curl -s -X GET "$BASE" \
  -H "$AUTH"

The channel object reports state, connected and logged_in. A linked device can be disconnected, so logged_in alone is not proof of a live socket. If connected_stale is true, connected is the last known observation. Read last_error for the reported failure rather than guessing from a disconnect.

What the phone does

The phone owner approves pairing and can revoke the device from the phone. This guide does not promise a phone-offline duration or a device-count allowance. Use the current channel state to see what the API observes.

Connection changes and recovery

Signal	Meaning and action
PAIRING	Pairing is in progress. Complete the approval on your phone.
Post-pair 515	The service reconnects the paired device to complete login.
Routine socket disconnect	The service schedules a reconnect for the linked session. Check channel state before sending.
Phone-side logout or unlink	The device is cleared and the channel returns to NEW. Request a new QR or pairing code to link again.

Automatic recovery resumes linked devices; it does not approve new pairings on your behalf. You can link, unlink on the phone and link again. There is no extra cooldown or operator grant for that user action.

Questions

Is the channel token a pairing code?: No. The token authenticates API requests. QR and pairing codes are used to approve a linked device on the phone.
Does logged_in mean connected?: No. They are separate fields. Read connected and state too, and check connected_stale when it is present.
Does a 515 mean pairing failed?: The post-pair 515 asks the linked device to reconnect to complete login. The service handles that reconnect.
Can I link again after unlinking on the phone?: Yes. Request a new QR or pairing code and approve it on the phone. Automatic paths do not create a new pairing for you.

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HelloHop is an independent WhatsApp API for developers: send and receive messages, automate groups and communities, and get signed webhooks with a free sandbox. Not affiliated with WhatsApp or Meta. You link your own number.