User Authentication pay per use.
Your agents autonomously verify users via SMS, handle one-time passwords, and manage transactional messaging — without you touching a vendor account. Billed per verification.
Built for teams that need identity verification without the vendor overhead.
Four shapes of customer who benefit most. If you recognize your workflow, the per-verification model is in your favor.
Verification as just another tool call.
MCP discovery and pay-per-call payment let an autonomous agent self-onboard at runtime. The agent sends the OTP, polls for the user's code, and confirms identity — no human-managed Twilio account anywhere in the loop. The flow unblocks itself once verified.
Gate actions behind a verified phone number.
Wallets, marketplaces, and SaaS products add phone verification to sensitive actions through one endpoint. Per-verification billing maps cleanly to per-user patterns — traffic bursts during high-activity periods scale linearly instead of hitting a monthly plan ceiling.
Reduce fake accounts without adding friction.
Verify a new user's phone number before granting access. OTP delivery in under ten seconds globally means legitimate users barely notice the step. No number provisioning, no carrier warm-up period — verification works on the first call.
Step-up authentication before high-value actions.
Require an OTP confirmation before executing flagged or high-value transactions. Step-up authentication without re-architecting the identity layer — the existing flow adds one verification call, the transaction only proceeds on success.
Stop wiring up Twilio for every project.
Connect a wallet, hit the endpoint, and your first OTP lands on a real phone in seconds. If you don't verify for a month, you don't pay for the month. No vendor account to create, no API keys to rotate, no shared secret in your agent logs. That's the entire deal.
- Global SMS coverage
- No vendor account
- MCP + pay-per-call native
- Per-verification billing
The honest answers.
If something below doesn't cover your case, ping us — we answer directly, no SDR funnel.
What verification methods are supported?
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SMS one-time passwords (OTP) and transactional messaging — password resets, login alerts, and confirmation messages. The same endpoint handles all three shapes: send an OTP, verify a code the user entered, or dispatch a one-way transactional message.
Do I need a Twilio, Vonage, or other SMS vendor account?
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No. The gateway manages the SMS infrastructure entirely. You never sign up with Twilio, Vonage, or any carrier-level provider. Authentication is per-request via pay-per-call — connect a wallet, sign the request, send the verification.
How does the OTP flow work?
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Two calls. First, POST to /verifications with the user's phone number — the gateway sends a 6-digit code via SMS. Second, when the user enters the code, POST to /verifications/check to confirm it. The check endpoint is free and rate-limited. Billed only on the first call.
Can an autonomous AI agent run the full OTP flow without human intervention?
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Yes — that's a primary design point. The agent sends the OTP to the user's phone, the user enters the code into whatever UI the agent is driving, and the agent verifies the code autonomously. MCP discovery and pay-per-call payment mean the agent self-onboards without a human creating an account.
How is billing calculated?
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Per verification attempt — one charge when the send endpoint is called, regardless of whether the user enters the correct code. Transactional messages are billed per dispatch. Idle periods cost nothing.
What countries are supported for SMS delivery?
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180+ countries. Coverage includes all major markets in North America, Europe, Asia-Pacific, Latin America, and Africa. No number provisioning or carrier warm-up is needed — delivery is available on the first call.