The scariest failure isn't the loud one. It's the one where everything looks fine.

Why let an AI answer?

When I’m under a desk at a client’s office with a screwdriver in my hand, I can’t take a call. Voicemail works, but most people hate leaving one. What I wanted:

Once the number lived at Telnyx, that became possible. Telnyx has a feature called Call Control: every time a call comes in, Telnyx asks your server what to do with it, and your server answers with commands like “answer,” “transfer” or “hang up.” My texting server already handled Telnyx’s texting webhooks. Now it handles calls too.

The rules

Here’s what happens when you call my business number today:

1. On my VIP list? Family and the people I most need to hear from (31 right now) ring straight through to my phones, showing their real caller ID, just like a normal call.
2. Blocked? The call ends. Spammers don’t get an AI to chat with.
3. Everyone else gets an AI receptionist. It says up front that it’s an AI and that the call is recorded, then takes the message: who you are, what you need, how to reach you.
4. I get a summary in Telegram right away, plus a digest every morning at 7:30.

At night (10 PM to 7 AM), only family and urgent VIPs ring through. Everyone else gets the AI. I can change any of it from Telegram with commands like /vip, /block and /night, with no app or website needed.

Want to see the whole route a call takes? The diagram on the section front page has a “Someone calls” button.

The three silent days

The move from “my office phone system answers my number” to “my server answers my number” happened on the night of September 21. The AI part worked. Calls got answered and messages showed up in Telegram.

What nobody noticed: the old path had been doing two jobs the new one didn’t.

• The VIP list stopped ringing through. My family and best clients were getting the AI too.
• The voicemail safety net was gone. If the AI couldn’t start, the call just ended. If my server was down, there was nothing behind it at all.

Nothing errored. Nothing alerted. The calls looked handled. It took three days before a full review of the phone setup on September 24 turned it up.

The fix

On September 25 I told Leo to fix all of it, and it went in that night:

• VIP ring-through is back, transferring the call to my office phone system so it rings my phones. That surfaced a sneaky gotcha. By default, a Telnyx transfer shows the number that was dialed as the caller ID, not the person calling. My phone system saw “my number calling my number,” didn’t recognize a VIP, and sent my VIPs to voicemail. The transfer now passes along the real caller’s number.
• If the AI can’t start, the call goes to my regular phone system and voicemail instead of hanging up.
• If my server is down, Telnyx falls back to a small backup responder on the office phone system, so a call always lands somewhere.
• Spending caps on outbound calls, so a bug can’t run up a bill.
• A monitor that checks the whole call path every five minutes and pings my Telegram the moment anything drifts from how it should be.

That round shipped with 100 of 100 tests passing. The monitor is the part I care about most. The three silent days weren’t caused by bad code. They were caused by a change with nothing watching it.

What it costs

In the last 30 days, the AI receptionist answered about 155 calls across all my lines, for a total of $10.55. That’s about seven cents a call to never get interrupted by an extended-warranty robot again.