How to set an AI phone system inside your own CRM

Every few days a partner asks us the same question with a different CRM in it. A property manager running tenants out of a home-grown back office. A recruiting agency on a niche ATS. An insurance broker whose "CRM" is an Airtable base with 40 fields nobody else would understand. None of them want to leave that tool. They just want to make phone calls.

That used to mean one of two bad options: keep the phone system in another tab and copy notes across by hand, or build telephony yourself, tough, ah?. But don't worry, this article is about a third option, and about exactly how it works.

Why custom CRMs are the hardest place to put a phone

Native integrations are built for the mass market. They know what a HubSpot contact or a Salesforce lead looks like, and they write calls to it. Your CRM does not have leads. It has tenants, job sites, loan files, candidates, policies. The call belongs on one of those, next to the fields that make your business yours.

So the choice has always been between a phone system that does not know your data, and a phone system you have to build. Building one is a bigger project than it looks from the outside.

Three ways in: the dialer, webhooks and the API

Every Allo integration with a custom CRM is built from the same three pieces. Each one answers a different question.

The embedded dialer, our newest piece

The embedded dialer puts the full Allo dialer inside your app with a single iframe. Your team signs in to Allo inside it once, and from then on calls start and ring right where they work. It talks to your page in both directions through postMessage.

Tip

One step before it works

Embedding is switched on per domain. Email [email protected] with the domains your CRM runs on, then drop in the iframe.

Webhooks: the part that makes it AI native

The dialer tells your page what is happening. Webhooks tell your server what happened, with everything the AI produced. The one that matters most is call.completed, sent about 30 seconds after the call hangs up, with the summary, the full transcript, the recording URL, the tags, the result and any fields the AI receptionist collected.

There are 22 event types in total, from call.received (which already carries the matching person, company and deals) to sms.received, tag.added and thread comments. Every delivery is signed, retried up to 8 times over about 27.5 hours, and can be replayed after an outage.

The API: when your CRM gives the orders

The REST API is how your CRM makes Allo do things. The endpoints custom CRMs use the most:

• Load the power dialer from any list in your CRM, for yourself or for a teammate, with names and companies attached.
• Send a text from the team's Allo number, so it lands in the same thread as the calls.
• Search every call and text by keyword across transcripts, summaries and messages.
• Read and add tags so your CRM filters and Allo filters stay the same.
• Write summary templates so the AI summary follows your fields, not a generic format.
• Configure the AI receptionist per line: prompt, knowledge, business hours, transfer rules.

One call, end to end

Here is what a single outbound call looks like when both channels are wired. The browser events drive the screen while the call is live. The webhooks carry the result to your database once it is over.

1. 01The rep clicks a number in your CRM Your page sends dial with the number. The embedded dialer opens with the call ready, on the rep's own Allo line.
2. 02The call starts The dialer fires outgoing_call to your page and Allo fires call.triggered to your server. Use whichever is closer to the thing you want to update.
3. 03The prospect picks up call_answered in the browser. Show the talk track for this deal stage, or start your own timer.
4. 04The rep hangs up call_ended in the browser. Ask for the outcome now, while the rep still remembers it.
5. 05About 30 seconds later call.completed reaches your server with the summary, transcript, recording and tags. Your handler writes them to the record, in your schema.

1. 01

   The code: the embed

   <iframe id="allo" src="https://web.withallo.com?variant=dialer" allow="microphone; autoplay" style="width: 376px; height: 640px; border: 0;" ></iframe> <script> const ALLO = "https://web.withallo.com"; const dialer = document.getElementById("allo").contentWindow; // 1. Every phone number in your CRM becomes a call button document.querySelectorAll("[data-phone]").forEach((el) => { el.addEventListener("click", () => { dialer.postMessage( { source: "allo-host", type: "dial", payload: { phone_number: el.dataset.phone } }, ALLO ); }); }); // 2. Your CRM reacts to what happens on the call window.addEventListener("message", ({ origin, data }) => { if (origin !== ALLO || data?.source !== "allo-dialer") return; switch (data.type) { case "incoming_call": openCallerRecord(data.payload); break; // screen pop case "outgoing_call": markRecord("on a call"); break; case "call_ended": askForOutcome(); break; } }); </script>

2. 02

   The code: writing the call into your CRM

   // POST /webhooks/allo (subscribed to call.completed and sms.received) app.post("/webhooks/allo", express.raw({ type: "application/json" }), async (req, res) => { // 1. Verify the webhook-signature header first (see the Allo docs) // 2. Deduplicate on the webhook-id header: delivery is at least once res.sendStatus(200); // answer within 20 seconds, work in the background const { topic, data } = JSON.parse(req.body); if (topic !== "call.completed") return; const number = data.type === "INBOUND" ? data.from_number : data.to; const record = await crm.findByPhone(number); // your lookup, your schema await crm.addActivity(record.id, { kind: "call", direction: data.type, // INBOUND or OUTBOUND outcome: data.result, // ANSWERED, VOICEMAIL, TRANSFERRED_AI... duration: data.length, // "4m 22s" summary: data.summary, // the AI summary tags: data.tags, recording: data.recording_url, transcript: data.concatenated_transcript, rep: data.user_email, collected: data.data_collected, // fields the AI receptionist gathered }); });

3. 03

   The code: a "call this list" button

   Any filtered view in your CRM can become a calling session. One request to append numbers to a rep's power dialer queue, and they dial back to back from the embedded dialer. curl -X POST https://api.withallo.com/v2/api/dialing-queues/current/numbers \ -H "Authorization: Api-Key YOUR_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "email": "[email protected]", "numbers": [ { "number": "+14155550142", "name": "Dana", "last_name": "Whitfield", "company": "Harborline" }, { "number": "+14155550187", "name": "Marcus", "last_name": "Bell", "company": "Bell & Sons Roofing" } ] }'

What lands on the record

This is the part your team will actually feel. The rep does not type notes. The record fills itself, and it fills itself with what your business needs, because you decide where each field goes.

1iframe to embed the dialer

~30s from hang-up to summary on your server

22webhook event types

8automatic retries per delivery

The top 10 CRMs, and where the custom part starts

Most teams are not on a fully custom CRM. They are on a big one they bent into shape with custom objects, extra apps and an internal tool or two on the side. Here is how Allo meets the ten most used CRMs, and when to reach past the native sync.

Less common CRMs Allo already syncs with natively

Before you write a line of code, check this list. Plenty of the niche CRMs partners ask about are already native: connect them in a few clicks and calls log themselves, with the AI summary and the recording. See the full list in the integrations overview.

The CRMs teams build themselves

Then there is the long tail, and it is where most of the partner questions come from. Four recipes we see again and again:

Note

Native sync is right when

Your CRM is on the integrations list Calls belong on standard contacts and deals You want it running today with no code

Note

API + embedded dialer is right when

Your CRM is home-grown, vertical or not listed Calls belong on your own objects You want the phone inside your screen, not next to it

Tip

Building a CRM for other people?

If you sell vertical software or a CRM, the Allo reseller program is built for you: embed Allo in your product, bundle it with your offer and bill it at your own price.

Where to start this week

1. 01Email [email protected] with the domains your CRM runs on, to switch on the embedded dialer.
2. 02Paste the iframe on your record page and wire the dial event to your phone fields.
3. 03Create an API key in Allo settings and subscribe a webhook to call.completed.
4. 04Map the summary, tags and recording to your own fields. That mapping is the whole integration.
5. 05Add one button that loads a filtered list into the power dialer. Your reps will ask for more.

Which CRM are you using?

Seriously, tell us. Every niche CRM we hear about makes the next integration easier, and the most requested ones become native. Send the name to [email protected], or book a demo and we will sketch your setup with you, on a call, obviously.