Key Takeaways
- list_devices MCP tool failures are empty arrays, stale last-seen, and agents treating a listing as permission to blast.
- The tool wraps the devices REST resource. Confirm names in Developer Center. Not a first-party plugin.
- Last-seen “online” at 17:00 is not overnight health. Doze still applies.
- Free is 1 device. Starter’s 2 is the usual OTP + spare pair.
- You bring phones and airtime. Platform pricing is devices plus volume.
MCP Server for Android SMS Gateway: List_devices MCP tool — failure modes is inventory, not routing. Multi-device · Laravel deviceIds · build overview failures. Live fields: Developer Center. Spec: MCP.
Devices and send volume. You fund every SIM.
A list is a snapshot. Last-seen is already aging while the model talks.
list_devices is a read, not a send grant
Agents that chain list → send_bulk without a gate are a campaign button. Rate limits and safety.
Showing a device id is not proof it can send at 03:00. It is proof the control plane still has a row.
List tool failure table
| Symptom | Likely cause | Check |
|---|---|---|
| Empty array | Wrong account key / never paired | Setup |
| Missing spare phone | Second device unpaired | Panel, not the prompt |
| last-seen hours ago | Doze, Wi-Fi, charger | Overnight |
| Tool timeout | Hung GET | Http timeout on the wrapper |
| Agent picks id 0 | Hallucinated schema | Developer Center ids |
Empty list vs stale last-seen
Empty is pairing. Stale is ops. Logging should record last-seen, not “online: true” inferred by the model. MCP audit.
Wrong id in the next send
OTP on the campaign chassis is a product incident. Pin deviceIds in the send tool from config, not from “whichever the list returned first.”
Shared vs owned
Some account roles see devices they cannot USSD or fully control. If a tool lists a phone the key cannot send through, the next POST fails — that is authorization, not a puzzle to bypass. App install.
Next steps
Call list_devices, compare to the panel, canary the id you intend. 300 lifetime SMS on Free will not cover two production radios.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- SMS API documentationLive endpoint reference
- device and SMS volume pricingPlans and allowances
- Android SMS gateway product guideDefinition, product, and how to buy
- download the Android gateway appGet the APK
