> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tuco.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Limits & Constraints

> The technical limits that shape how Tuco sends — line activation time, first-message rules, per-line caps, ban behavior, A2P for Android, and what Tuco can't do.

**Tuco sends real iMessage from real Apple hardware, so it inherits Apple's rules — these are the hard constraints to plan around.** This page is a quick operational reference; each row links to the detailed doc. For the full plain-English rundown of *why* each limit exists, see [tuco.ai/limitations](https://tuco.ai/limitations).

## The constraints at a glance

| Constraint                         | What it means                                                                                                                                                                | Details                                                      |
| ---------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------ |
| **Line activation takes \~48h**    | A new line runs on a real Apple device + carrier eSIM that the carrier must activate first. Budget 48h+ from order to first message.                                         | —                                                            |
| **First-message rules**            | On the first-ever message to a contact, links aren't clickable and you can't send an attachment/voice note. Send a plain text first; once they reply, everything works.      | [Send messages](/features/send-messages)                     |
| **Per-line sending caps**          | Default **50 new-contact sends/day**, **150 total sends/day** per line, and **\~7 first-touch sends/hour** so a line never bursts. All three can be raised on request.       | [Rate limits](/features/rate-limits)                         |
| **Bans are a switch, not a score** | A small, absolute number of "Report Junk" taps can **permanently** ban a line — regardless of your send rate. Only message people who opted in.                              | [Line health](/troubleshooting/line-health-and-restrictions) |
| **No number porting**              | Tuco can't port in your existing number, and a banned number can't be recovered — only replaced with a new one. Don't print a line on business cards.                        | —                                                            |
| **Android needs A2P**              | iPhone contacts get iMessage; Android contacts get SMS from an **A2P 10DLC-registered** number you bring and register. Or send to iPhone-only and skip A2P.                  | [Compliance](/guides/imessage-compliance-tcpa)               |
| **Availability checks are capped** | Tuco can check **\~70 numbers/line/day** for iMessage support — enough for routing new leads, not for scanning a large list.                                                 | [Check availability](/guides/check-imessage-availability)    |
| **One line = one identity**        | Reps can share a line for outbound calls, but the contact card and forwarding are fixed per line — no per-rep identity switching.                                            | —                                                            |
| **No FaceTime audio yet**          | On the roadmap, not live. You can still call out on the same number.                                                                                                         | —                                                            |
| **No HIPAA**                       | Apple won't sign a BAA for iMessage, so Tuco **can't** be HIPAA compliant. Never send protected health information (PHI). Booking/reminders are fine; medical detail is not. | —                                                            |

## A few that trip people up

### iMessage doesn't blast

The per-line caps exist because iMessage rewards personal, opt-in sending and punishes volume. Tuco is a **speed-to-lead** tool — reach people the moment they raise their hand (form fills, ad opt-ins, hot inbound). To scale, add lines; don't push one line harder. See [line health & restrictions](/troubleshooting/line-health-and-restrictions).

### Bans and replacements

If a line is banned, you get a free replacement on the first occurrence (later replacements may carry a fee). A banned number can't be recovered — only replaced. Treat every line as a working sender that could one day need swapping, not a forever number.

### No PHI, ever

Because Apple won't sign a BAA, no service built on iMessage — Tuco included — can be HIPAA compliant. Clinics and medspas can use Tuco for booking and reminders, but never for diagnoses, records, or any medical detail.

## Frequently asked questions

<AccordionGroup>
  <Accordion title="How many iMessages can I send per day?">
    Per line, the default is 50 new-contact sends and 150 total sends per day, paced to \~7 first-touch sends per hour so a line never bursts. All three can be raised on request, and adding lines multiplies your capacity. See [rate limits](/features/rate-limits).
  </Accordion>

  <Accordion title="Can Tuco blast a big cold list?">
    No — by design. iMessage penalizes high-volume cold sending with permanent bans, so Tuco caps each line and is built for personalized, opt-in, speed-to-lead outreach. See [line health](/troubleshooting/line-health-and-restrictions).
  </Accordion>

  <Accordion title="Can I bring my own phone number?">
    No. Tuco can't port in an existing number. You get a new number, and if a line is ever banned it's replaced with another new number (the old one can't be recovered).
  </Accordion>

  <Accordion title="Is Tuco HIPAA compliant?">
    No, and it never can be — Apple won't sign a BAA for iMessage. Don't send protected health information. Appointment booking and reminders are fine; medical detail is not.
  </Accordion>

  <Accordion title="How do I reach Android users?">
    Android contacts receive SMS from an A2P 10DLC-registered number that you bring and register (brand + campaign). Or message iPhone contacts only and skip A2P entirely.
  </Accordion>
</AccordionGroup>

<Card title="Rate limits & sending caps" icon="gauge" href="/features/rate-limits">
  The exact per-line daily and hourly caps, and how to raise them.
</Card>