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Hosted MCP for SMS OTP and transactional SMS agents

Robase · 2026-09-20

An AI coding agent can send a real OTP if it can call the same prepaid API your backend already uses. Robase now exposes that path as hosted MCP — a Model Context Protocol server over Streamable HTTP — so Cursor, Claude, ChatGPT-style agents, or your own bot can send and verify SMS OTP and transactional SMS without a custom integration layer.

This is the same workspace, the same credits, and the same error.type values as REST. It is not a second product and not a marketplace listing. Setup lives in the AI agents guide. The marketing overview is on /mcp.

What hosted MCP is

MCP is a standard way for a host (an editor, a chat app, or a bot runtime) to discover tools and call them. Robase’s server speaks Streamable HTTP at https://api.robase.dev/mcp.

You authenticate with a Bearer token, the same family of keys as REST:

  • Workspace API keys start with robe_
  • Agent keys start with robe_agent_

Create an Agent key under Dashboard → API keys. Same workspace scope as a standard key. Revoke it there to stop the next tool call — there is no auth cache.

Every send still spends prepaid credits. Hosts that support tool approval should require approval on send_otp and send_sms until you turn that off.

How to connect

  • URL — https://api.robase.dev/mcp
  • Transport — Streamable HTTP
  • Auth — Authorization: Bearer robe_… or robe_agent_…

In Cursor: Settings → MCP → add the URL and the Bearer header. MCP Inspector works the same way. Other hosts that speak Streamable HTTP take the same URL and header — we do not list storefronts or claim a Cursor App Store listing.

Idempotency-Key is set automatically (UUID) on every POST tool if the caller omits it.

Phase 1 tools

Phase 1 is six tools. Each maps to the same REST path as the AI agents guide.

  • get_pricing — GET /v1/pricing. No side effect. Call this for destinations; treat listed:true as marketed markets.
  • send_otp — POST /v1/otp/send. Spends credits.
  • verify_otp — POST /v1/otp/verify. Consumes an attempt.
  • get_otp — GET /v1/otp/{id}. No side effect. The code is never returned.
  • send_sms — POST /v1/sms/send. Spends credits; antispam may block and refund.
  • get_sms — GET /v1/sms/{id}. No side effect.

There are no payment, top-up, team, KYB upload, webhook CRUD, or admin tools. On insufficient_credits, a human tops up under Billing. Daily credit cap for agent keys is unlimited by default, same as REST — a host-side limit of 50–100 credits/day is a reasonable extra control and is not enforced by Robase in Phase 1.

REST clients stay Node.js (@robasedev/sdk), Go (github.com/mantissatech/robase-sdk-go), and PHP (robase/sdk). There is no Python SDK. MCP does not replace those packages; it is another way to call the same six operations.

Claim-safe rules for agents

Copy this into a system prompt, or use the sample on the AI agents guide. It matches the MCP instructions field.

  • Call get_pricing. Treat listed:true as marketed markets. The live listed set is NG, GH, KE, ZA, GB, BJ, CI, US.
  • Do not invent delivery percentages, SLAs, or extra countries.
  • Prefer OTP-shaped tests: Your Robase test OTP is 123456. Do not send Hello or Good morning — those may be blocked and refunded.
  • Match failures on error.type. Handle insufficient_credits, account_temporarily_restricted, kyc_required, and sms.blocked.
  • Never paste API keys into chat.

Credits and priced markets

1 credit = ₦6. Signup trial is 10 credits (₦60) — that is not the US message price. A United States destination is 100 credits (₦600).

Published priced markets are Nigeria, Ghana, Kenya, South Africa, the United Kingdom, Benin, Ivory Coast, and the United States. Nigeria, Ghana, Kenya, South Africa, Benin, and Ivory Coast use multi-provider routing with automatic failover; the UK and US routes are currently single-provider. Other destinations are on request. We do not publish a delivery-rate percentage.

The same prepaid wallet covers OTP and transactional SMS, whether the send came from REST or from MCP.

What to do next

  1. Create an account at https://robase.dev/signup. New workspaces get the 10-credit trial.
  2. Create an Agent key at https://robase.dev/app (Dashboard → API keys).
  3. Point the host at https://api.robase.dev/mcp with Authorization: Bearer robe_agent_….
  4. Send an OTP-shaped test, not a greeting.

The full connect steps, tool list, and sample prompt are in the AI agents guide. Product surface and FAQ: hosted MCP. REST OTP and SMS remain on the OTP API and SMS API pages.