Key Takeaways
- Scenario 876 is barber Saturday chair OTP — not salon, calendar deposits, waitlists, studio door-codes, telehealth, vet, garage, driving, notary, implant, visa, physio, optician, or tattoo session.
- Chair OTP is P0. Walk-in ready is P1. Product merch waits.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free is 300 SMS lifetime, 1 device. Developer is 25,000 SMS per year.
- Starter is 2 devices; the shop spare still counts.
- A cancelled chair at 09:05 must kill the 09:20 OTP still queued.
- Pin OTP deviceIds. Newsletter never shares the chair radio.
Summary
Scenario 876 is the Saturday barber. Chair OTP first, walk-in ready second, product merch held until the last seat sits. Service pricing is based on device count and total SMS sent through the gateway. You need a working Android phone with a SIM and SMS credit from your mobile operator. Operator message costs are yours—we do not sell carrier SMS balance.
If the sale CSV left at 09:00 and the client is still at the door, you did not seat a chair. You advertised.
Not a CodeCanyon “barber SMS” pack. Device meters apply — Twilio vs Android SMS gateway.
Key takeaways
- Scenario 876 is barber Saturday chair OTP — not salon, calendar deposits, waitlists, studio door-codes, telehealth, vet, garage, driving, notary, implant, visa, physio, optician, or tattoo session.
- Chair OTP is P0. Walk-in ready is P1. Product merch waits.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Free is 300 SMS lifetime, 1 device. Developer is 25,000 SMS per year.
- Starter is 2 devices; the shop spare still counts.
- A cancelled chair at 09:05 must kill the 09:20 OTP still queued.
- Pin OTP deviceIds. Newsletter never shares the chair radio.
Related reading
OTP and 2FA SMS, appointment reminders, how an Android SMS gateway works, GOV.UK SIC activities.
Context
Walk-ins stack at 09:00. Clients reply from the pavement. Saturday still wants a product CSV.
Free (300 SMS lifetime) is a rehearsal shop. Developer is 25,000 SMS per year.
Core scenario guidance
Chair OTP is P0. Cancelled slots kill queued codes. Timezone is the shop city.
Chair OTP roles
| Role | When | Typical fail |
|---|---|---|
| Chair OTP (P0) | Client at the door | Queued behind Saturday sale |
| Walk-in ready (P1) | Chair free | Sent after the slot was cancelled |
| Product merch | Held until last chair seated | Released at 09:00 into OTP |
| Portal login OTP | Own pool, always | Dumped onto the chair SIM |
Cost and ownership
Priced by devices and SMS send volume. You use your own phone and operator SMS credit. The shop spare is a billed device. Codes burn airtime.
Name a Saturday 08:30–14:00 on-call, not only weekday reception.
Operations
08:50 canary both radios. Abort: hold merch, keep portal OTP, skip queued chair if cancelled. Do not “resend all walk-ins.”
Security and compliance
Short codes only. No card last-four plus full name in one SMS. Authenticate booking hooks. Merch is promotional.
Decision guide
Ship when 08:50 canary is green and cancelled slots kill OTP. Delay if phones lock Friday night. If handsets are forbidden, CPaaS for chair OTP.
Checklist
- Primary + shop spare paired.
- 08:50 canary.
- Cancel kills queued OTP.
- Chair isolated from merch.
- Portal OTP own pool.
- Airtime before Saturday.
- Battery exemptions both OEMs.
- Shop-city locale.
- Chair on-call named.
- Device cap includes spare.
Next steps
Review device and SMS volume pricing, device setup, SMS API documentation.
Deep dive: production hardening
Saturday cleaner pulling USB at 08:20 is an outage at 09:00. Watch DLR, not booking 200s.
Deep dive: scaling and failure modes
Multi-chair Saturdays add devices before inventing a hidden unlimited-handset SKU. Raise OEM ceilings; fair-use remains.
Deep dive: integration discipline
Idempotency on booking_id + kind (chair|walkin). MCP is a REST wrapper — live fields in Developer Center.
Priced by devices and SMS send volume. You use your own phone and operator SMS credit.
08:50 chair drill
Canary both radios. Cancel a dummy slot; confirm OTP dies. Hold merch during the wave.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- OTP and 2FA SMS on AndroidAuthentication flows
- multi-device and dual SIM routingCapacity and failover
- SMS delivery reports (DLR)Delivery status tracking
- SMS API documentationLive endpoint reference
