Threadline

Connecting Messenger

Threadline connects to Facebook Messenger through Meta's Messenger Platform, keyed by a Facebook Page rather than a phone number.

Keep Meta's dashboard and your Threadline panel open in two tabs. You will copy values back and forth.

In plain words

What this is. Connecting your Facebook Page to Threadline, so messages people send to the Page on Messenger arrive in your Inbox and the AI can answer them.

What you will end up with. Three values copied from Meta into Threadline (your Page ID, a Page access token and the app secret), and two values copied from Threadline into Meta (a callback URL and a verify token).

What you need. A Facebook Page you manage. The app must be able to connect to it, so sign in to Meta with an account that has a role on that Page.

For what a channel is and how to manage one afterwards, see Channels.

1. Create your Meta app and add the Messenger use case

Everything below happens inside a Meta developer app, so this comes first.

  • No Meta app yet? Follow Create your Meta app and, on the use cases step, tick Engage with customers on Messenger from Meta. You can tick WhatsApp and Instagram on the same app, so you only do this once.
  • Already have an app (for example from WhatsApp or Instagram)? Open its Dashboard, click Add use cases, and add Engage with customers on Messenger from Meta.

When the app exists, its Dashboard lists "Customize the Engage with customers on Messenger from Meta use case". That is where the next step starts.

2. Connect your Facebook Page

  1. In your Meta app, open Use cases in the left menu and click Customize next to Engage with customers on Messenger from Meta.
  2. In the left menu of that page, open Messenger API Settings.
  3. Find the box 2. Generate access tokens. It says "No FB pages yet". Click Connect.
  4. Sign in with Facebook and choose the Page (or Pages) you want customers to message. Finish the prompts.

The left menu of this use case also has Permissions and features, API integration helper, Instagram settings and Webhooks. You only need Messenger API Settings here.

3. Copy the Page ID and generate the token

After connecting, the box lists your Pages. Each row shows:

  • the Page name with its Page ID (the small blue number under the name). Copy it.
  • a Token column with a Generate button. Click it and copy the token.

Use the copy of the Page ID and token for the same Page.

Generate tokens carefully. A token generated here is tied to that Page. Make a note of which Page it belongs to, and do not mix them up if you connected several. For a token that does not expire, make a System User token. See Make the token permanent and grant it your Page instead of a WhatsApp number.

4. Copy the App secret

In the app's left menu, open App settings → Basic and click Show next to App secret. Copy it. It is the same value you used for WhatsApp, because it belongs to the app. See Create your Meta app.

5. Create the channel in Threadline

  1. In Threadline, go to Channels and click Connect a channel.
  2. Fill in the dialog:
    • Channel type: Messenger
    • Name: for example "Messenger Support"
    • Assistant: pick one now, or later from the channel's card
    • Facebook Page ID (step 3)
    • Access token (step 3)
    • App secret (step 4)
  3. Click Connect.

6. Copy the Callback URL and Verify token

Threadline opens the channel's page. In Finish setup in Meta's dashboard, copy the Callback URL and the Verify token.

The Callback URL must be your real, public HTTPS address. A http://localhost address cannot be reached by Meta.

7. Register the webhook in Meta

  1. Back in Meta, open Use cases → Customize for Messenger, then Messenger API Settings.
  2. In 1. Configure webhooks, paste the Callback URL and Verify token from Threadline.
  3. Click Verify and save. Meta checks your address once. It only works over HTTPS with a matching verify token.
  4. In 2. Generate access tokens, find your Page and click Add Subscriptions. Tick messages (and messaging_postbacks if offered) and save. Until you do, the row says "No fields subscribed" and no messages arrive.

Verification fails? Same causes as WhatsApp: no HTTPS yet, a Verify token copied with extra spaces, or a Site URL mismatch. See Troubleshooting.

8. Test it

Send your Page a message on Messenger from another Facebook account. It should appear in Threadline's Inbox within a few seconds and, if a knowledge base is linked, get an AI reply. Messenger fully supports outbound images, unlike Instagram.

Testing before your app is published? Meta only delivers messages from people who have a role on the app.

  • Add the sender as a tester. In the Meta dashboard open App roles → Roles and add them, then ask them to accept the invite at developers.facebook.com. Otherwise Meta silently drops their messages.
  • Going live needs App Review. The page's box 3. Complete App Review shows a Request permission button for pages_messaging. Messaging real customers requires it to be approved, and the app must be published.

Comment to DM: answer comments automatically

When someone comments a word on one of your Page posts, you can reply in public and send them a private message with the details. The private message opens a normal conversation that the AI and your team continue.

Set it up

  1. Add the comment permissions in your Meta app: pages_messaging for the private message and pages_manage_engagement for the public reply. Meta reviews these before they work for other people's accounts (App Review).
  2. In the Meta dashboard, subscribe the webhook to the feed field.
  3. In Automations, start from Comment keyword → DM. Choose the word to look for and, if you like, the posts it applies to.
  4. The flow has two steps: Reply to the comment (one of several versions is picked at random) and Send a private message to the commenter.

Rules from Meta that the steps follow

  • One private message per comment, within 7 days of it. After that the step stops with a clear reason.
  • The private message is plain text. Once the person answers, you can write back as usual within 24 hours of their answer.
  • Your own comments and replies are ignored, so an automation never answers itself.
  • Under one post, at most 500 automated replies an hour are sent, to stay inside Meta's limits.

Comments appear on the contact's page under Comments on your posts.

Other differences from WhatsApp

  WhatsApp Messenger
Pre-approved templates Yes (Meta review required) No — Threadline sends template replies as plain text on this channel instead.
Text message limit 4096 characters 2000 characters
Typing indicator Supported Supported
Outbound images Supported Supported (a caption, if any, is sent as a separate follow-up message rather than attached to the image itself).