One Unified Inbox for Expandi. Every reply answered in under 5 minutes.
Expandi runs LinkedIn campaigns across multiple sender accounts. Underfive takes it from there. Every LinkedIn reply from every sender and client lands in one Unified Inbox, where AI inbox agents write a human-like response, send it from the same LinkedIn profile, follow up, and book the meeting on your calendar.
- 50 free replies
- No credit card
- One webhook URL for every sender
Reply via Expandi 
Read & classified
Interested · drafted in 48s 
Expandi gets the reply. Your Unified Inbox wins the meeting.
Expandi already collects LinkedIn replies in its inbox. The expensive gap is the hours between a prospect replying and someone on your team finding it, reading it, and writing back. Underfive closes that gap with one inbox across every sender and client, and agents that answer in minutes.
Reply time, around the clock
Every reply to an Expandi campaign gets a human-like response in under five minutes. Nights, weekends, and holidays included.
More likely to qualify the lead
Harvard Business Review found that firms contacting a lead within an hour were nearly seven times more likely to qualify it, meaning they reached a real decision maker, than firms that waited an hour longer (Oldroyd, McElheran and Elkington, HBR, March 2011). That window is the whole product.
Every sender. Same webhook.
Your Expandi API key and Secret key go into Underfive once. Underfive gives you one webhook URL, and you paste that same URL into each LinkedIn sender in Expandi. About a minute per sender.
Connected in three steps
Two account keys, one webhook URL pasted per LinkedIn sender. No changes to your campaigns.
Connect Expandi with your account keys, then add the webhook to each sender
Expandi gives you two credentials at the account level: an API key and a Secret key. Paste both into Underfive under Integrations. The integration does not work with only one. Underfive then gives you a webhook URL. Expandi webhooks live on each LinkedIn sender account, so open each sender in Expandi, paste the same Underfive webhook URL into its webhook settings, and enable the reply event. Repeat for every sender you want the inbox agents to cover.
- Both the Expandi API key and Secret key are required, added once at account level
- One Underfive webhook URL, pasted into each LinkedIn sender in Expandi
- Campaigns, sender accounts, and sequences are untouched
Integrations · Add tool Choose your senders and teach your inbox agents how you sell
Pick which LinkedIn sender accounts the inbox agents should reply for. Train them per sender or once for the whole workspace. Upload your offer, FAQs, pricing, and objection handling, connect Google Calendar or Outlook, then decide which reply categories send automatically and which wait for a human.
- Sender-level scopes: agents reply only for the LinkedIn senders you select
- Knowledge base per sender or per workspace
- Auto-send or Require Approval, per category
Replies are answered, followed up, and booked
When a prospect replies on LinkedIn, Expandi sends the conversation from that sender to your Unified Inbox. An inbox agent reads it, classifies it, writes a response in your voice, and sends it back through Expandi as a DM from the same LinkedIn profile. Interested prospects get a meeting on your calendar.
- Sent from the LinkedIn profile that received the reply, so the conversation stays with the same person
- Smart follow-ups when a thread goes quiet
- Every conversation in one Unified Inbox across senders and clients
Unified Inbox- Meeting bookedJordan MeyerThursday at 10:30 works. Talk then.Meeting booked
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Replied · autoEmily TranCan you send over a case study first?Replied · auto -
Follow-up · Apr 2Omar HaddadWe're mid-contract until Q2, circle back then?Follow-up · Apr 2 -
Needs approvalLena SchulzWho else at your company should I loop in?Needs approval
Already on Expandi? You are a few minutes away.
Sign up, add your API key and Secret key, paste the webhook URL into each LinkedIn sender, and the first reply that lands gets handled. Nothing changes in your campaigns or sender setup.
What happens to each kind of reply
Your inbox agents classify every LinkedIn DM reply before they act. You decide which categories auto-send and which wait for a human.
Interested
Answers, proposes times, and books the meeting on your calendar.
Pricing question
Replies with the pricing guidance from your knowledge base and moves toward a call.
Product question
Answers from your FAQs and offer details, in your tone of voice.
Objection
Handles the objection using your playbook and keeps the thread alive.
Not right now
Acknowledges, then schedules a follow-up for the timeframe they gave.
Referral
Thanks them and continues the conversation with the person they named.
Not interested
Closes politely and stops the thread. No more follow-ups.
Uncategorized
Goes to the approval queue so a human decides. Nothing is sent blind.
Categories and their behaviour are yours to edit per workspace. Nothing is sent without a category you approved.
Pick the senders. One inbox for all of them.
Expandi agencies run many LinkedIn senders for many clients. Underfive uses sender-level agent scopes, so you choose exactly which LinkedIn sender accounts the inbox agents reply for, give each one its own training or share one playbook, and see every client's replies in one view.
Sender-level scopes
Select the LinkedIn senders the inbox agents should act for. A sender without the webhook, or one you leave unselected, is untouched, so a client who wants manual replies keeps them.
Train per sender or per workspace
Give each LinkedIn sender its own voice, offer, and calendar, or train the agent once at workspace level and apply it to every selected sender.
One workspace per client
Connect each client's Expandi account to its own Underfive workspace with its own API key and Secret key. Agents, knowledge, approvals, and Slack channel stay separate per client.
A workspace per client
Team members are unlimited on every plan and workspaces are unlimited on Agency, so adding a client or a sender never adds a per-seat fee on the reply side.
Two tools. One job each.
Expandi owns LinkedIn automation and campaign sequencing. The Underfive Unified Inbox owns everything after the reply lands.
| Capability | Expandi | Underfive |
|---|---|---|
| Multi-account LinkedIn automation | — | |
| Campaign sequencing, connection requests, lead lists | — | |
| LinkedIn inbox per Expandi account | ||
| One Unified Inbox across every sender, client, and tool | — | |
| Writes a human-like reply to each LinkedIn response | — | |
| Replies within 5 minutes, 24/7 | — | |
| Negotiates times and books the meeting | — | |
| Follows up when a thread goes quiet | — | |
| Approval queue with Slack notifications | — |
Expandi integration FAQ
Everything people ask before connecting.
Does Underfive set up the Expandi webhook for me?
Not yet. Expandi webhooks are configured per LinkedIn sender inside Expandi. Underfive shows you one webhook URL for your workspace, and you paste that same URL into the webhook settings of each LinkedIn sender you want covered, then enable the reply event. It takes about a minute per sender.
Where do I find my Expandi API key and Secret key?
Both live at the account level in your Expandi settings. Copy the API key and the Secret key and paste both into Underfive under Integrations. The integration does not work with only one of them.
Do I need a different webhook URL for each sender?
No. Underfive gives you one webhook URL per workspace. Paste the same URL into every LinkedIn sender in that Expandi account. When you add a new sender later, paste it there too.
Does Underfive reply from my LinkedIn profiles?
Yes. Replies are sent through Expandi as LinkedIn DMs from the same LinkedIn profile that received the reply, so the prospect sees one continuous conversation with the same person.
Will this change my Expandi campaigns?
No. Campaigns, sequences, sender accounts, and connection requests keep running exactly as they do today. Underfive only acts on replies from senders that have the webhook.
Expandi already has an inbox. What does Underfive add?
The Expandi inbox collects LinkedIn replies inside one Expandi account. Underfive brings replies from every Expandi account, every sender, and every other tool into one Unified Inbox, and its inbox agents actually write and send the response, follow up, and book the meeting. With sender-level scopes you choose which senders the agents reply for.
Can I review replies before they go out?
Yes. Each reply category can be set to auto-send or require approval. Replies that need approval wait in your Underfive queue, and you can approve them from the app, from Slack, or through the Underfive MCP connector.
I run several clients on Expandi. How does that work?
Create one Underfive workspace per client Expandi account and connect each with its own API key and Secret key. Paste that workspace's webhook URL into each of the client's LinkedIn senders, select the senders, and train agents per sender or per workspace. Team members are unlimited on every plan, workspaces are unlimited on Agency, and the Unified Inbox shows every client in one place.
What does it cost?
Start with 50 free replies and no credit card. After that, plans are priced by agent credits. See the pricing page for current plans.
Stop leaving Expandi replies unanswered.
Connect in under five minutes. Your first 50 replies are free, and nothing changes in your campaigns.
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