Key Takeaways
- mcp server agentic otp verification concepts: the agent must not see or mint customer OTP digits.
- Hash the challenge in your app. SMS is a delivery side effect via POST /messages — not a model completion.
- MCP is a REST wrapper you host. Not a first-party Cursor or Claude plugin from us.
- If you must notify ops via a tool, use a dedicated key, pinned deviceIds, and allowlisted destinations.
- Priced by devices and SMS send volume. You use your own phone and operator SMS credit. Tool calls that hit the radio still spend airtime.
- Docs own fields. Prompts do not.
OTP is a product path, not a chat
Search intent for mcp server agentic otp verification concepts is whether an agent should text login codes. Service pricing is based on device count and total SMS sent through the gateway. Default: no. Your app hashes the challenge; the SIM delivers. OTP verification. Concepts hub: what is MCP for SMS.
If the six digits appeared in the model context, you did not build agentic OTP. You built a chat log of other people’s logins.
Spec: modelcontextprotocol.io. Docs: docs.sms-gateway.app.
MCP wraps REST; we do not ship a plugin
No first-party Cursor or Claude OTP plugin. You host a process whose tools call POST /messages. Laravel OTP (product path).
| Piece | App | Agent |
|---|---|---|
| Code | CSPRNG + hash + TTL | Must never see plaintext |
| Send | Queued POST /messages | No send_otp tool on production keys |
| Verify | Compare hash on submit | Not “did the SMS look right?” |
| Radio | Pinned deviceId | Allowlist staff numbers only if used |
Digits never enter the model
Log message ids, not codes. Log retention.
What a tool may do
Staff canary send, DLR lookup, last-seen — with allowlists. Not send_otp_to_anyone. Setup walkthroughs live on sibling spokes; this page is the policy.
When an agent is the wrong sender
Customer login, password reset, high-value auth. Keep those off MCP send tools. Priced by devices and SMS send volume. You use your own phone and operator SMS credit.
Agentic OTP checklist
- Code generated and hashed in-app.
- No plaintext OTP in prompts or traces.
- MCP is a REST wrapper you host — not our plugin.
- Production send tools allowlisted or absent.
- OTP device pinned; docs win.
Next steps
Keep auth in the app; use MCP for ops. Cursor MCP concepts. Pricing.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- OTP and 2FA SMS on AndroidAuthentication flows
- SMS API documentationLive endpoint reference
- device and SMS volume pricingPlans and allowances
- Android SMS gateway product guideDefinition, product, and how to buy
