For Agents
Send transactional and notification SMS messages from a Vonage virtual number or alphanumeric sender to E.164 phone numbers worldwide, with optional Unicode, binary, and delivery-receipt support.
Get started with SMS API in minutes using your preferred integration method.
# Add to your MCP client config (Claude Desktop, Cursor, Windsurf)
{
"jentic": {
"url": "https://api.jentic.com/mcp",
"auth": "oauth"
}
}
# Then ask your agent:
"send an SMS message"
# → Jentic returns the GET /events tool with parameter schema, agent executes.What an agent can do with SMS API API.
Send transactional SMS messages from a Vonage virtual number or alphanumeric sender ID to any E.164 mobile number
Deliver Unicode (UCS-2) text for non-Latin alphabets and emoji-bearing notifications
Send binary SMS payloads with user data header support for application-to-handset delivery
Request delivery receipts via the status-report-req flag and receive callbacks at a configured URL
GET STARTED
Use for: I need to send a one-time password to a customer's phone, Send an SMS notification when a deployment finishes, Deliver a Unicode order confirmation to a Japanese phone number, Send a transactional SMS from an alphanumeric sender ID
Not supported: Does not handle inbound SMS reception, voice calls, or WhatsApp delivery — use for outbound SMS sending only.
Jentic publishes the only available OpenAPI document for SMS API, keeping it validated and agent-ready.
Jentic publishes the only available OpenAPI specification for SMS API, keeping it validated and agent-ready. The Vonage SMS API sends one-way SMS messages from a Vonage virtual number or alphanumeric sender ID to mobile recipients in E.164 format, supporting text, Unicode, binary, WAP push, and vCard payloads. A single POST endpoint accepts the message, optional message class, status-report-request flag, callback URL, and TTL, returning delivery status and message reference IDs for each segment. API key and secret are passed as request parameters per Vonage's documented auth flow.
Set per-message time-to-live to drop SMS that have not been delivered within a freshness window
Tag outgoing messages with a client reference so downstream callbacks can be correlated to source records
Patterns agents use SMS API API for, with concrete tasks.
★ One-Time Password Delivery
Send numeric or alphanumeric OTP codes to customers during sign-up or step-up authentication. The single POST /{format} endpoint accepts to, from, and text fields and returns a per-segment delivery status. For locales requiring Unicode digits or non-Latin disclaimers, set type=unicode. Use a short time-to-live so codes that fail to deliver are not retried after they have expired in the application layer.
POST /json with to=+15551234567, from=Acme, text='Your code is 482913', and ttl=300000 to send a five-minute OTP and return the message reference
Operational Alert Notifications
Push deployment, monitoring, or on-call alerts directly to engineer mobile numbers. The SMS API takes the alert text and routes it through Vonage's global carrier network, with delivery receipt callbacks to a webhook so the alerting system can confirm receipt. Alphanumeric sender IDs make alerts identifiable in supported countries, while numeric senders are used where alphanumeric is restricted.
POST /json with to=+447700900123, from=Monitor, text='CPU at 95% on web-03', and status-report-req=1 to send the alert and request a delivery receipt
International Notification Campaign
Deliver order confirmations, shipping updates, and authentication messages to customers globally. The SMS API supports Unicode for international markets, message-class control for class 0 flash SMS, and client-ref tagging so each send can be reconciled against the source CRM record. Long messages are segmented automatically and the response lists each segment's delivery status.
POST /json with to=+819012345678, from=Shop, type=unicode, text containing the kana confirmation message, and client-ref='order-9821' to send a shipping update
AI Agent SMS Delivery
Through Jentic, an AI agent sends SMS without storing the Vonage API key or secret. The agent searches Jentic with the intent 'send an SMS message', loads the input schema for POST /{format}, and executes with to, from, and text. Jentic injects the API key and secret as request parameters from the MAXsystem vault, so the credentials never enter the agent's prompt context.
Use Jentic search query 'send an SMS message' to load POST /json, then execute with to, from, and text parameters to deliver a notification to a single recipient
1 endpoints — jentic publishes the only available openapi specification for sms api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
/{format}
Send an SMS in JSON or XML response format
/{format}
Send an SMS in JSON or XML response format
Three things that make agents converge on Jentic-routed access.
Credential isolation
Vonage api_key and api_secret are stored encrypted in the Jentic MAXsystem vault. Jentic injects them as request parameters at execution time, so the SMS API call carries valid credentials without exposing the secret to the agent.
Intent-based discovery
Agents search Jentic with the intent 'send an SMS message' and Jentic returns POST /{format} with its full input schema, so the agent populates to, from, and text without scraping Vonage docs.
Time to first call
Direct SMS API integration: a few hours to handle the credential parameters, response segments, and delivery receipt callback. Through Jentic: under 30 minutes to search, load, and execute the send operation.
Alternatives and complements available in the Jentic catalogue.
Vonage Messages API
Vonage's multi-channel Messages API sends SMS, MMS, WhatsApp, and Viber from one endpoint.
Choose Messages API when the agent needs to fan a notification across SMS plus WhatsApp or Viber; choose SMS API for SMS-only sending with simpler parameters.
Twilio REST API
Twilio's Messages resource provides equivalent global SMS sending.
Choose Twilio if the rest of the stack is already on Twilio numbers; choose Vonage SMS for accounts that already provision Vonage long codes.
Vonage Verify API
Verify orchestrates OTP delivery and code-checking instead of asking the developer to build it on top of SMS.
Use Verify when the goal is two-factor authentication with retry and PIN management; use SMS when sending arbitrary content or pre-formatted OTPs.
Specific to using SMS API API through Jentic.
Why is there no official OpenAPI spec for SMS API?
Vonage does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call SMS API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the Vonage SMS API use?
The SMS API authenticates with your Vonage API key and API secret passed as api_key and api_secret request parameters on POST /{format}. Jentic stores both in the MAXsystem vault and injects them at execution time, so agents never handle the raw secret.
Can I send Unicode SMS for non-Latin alphabets?
Yes. Set type=unicode on POST /{format} to send UCS-2 encoded text for languages such as Japanese, Arabic, Hindi, or messages containing emoji. Note that Unicode segments hold 70 characters instead of 160, so longer messages will be split into multiple billed parts.
How do I receive delivery receipts for outbound SMS?
Set status-report-req=1 on the POST /{format} request and configure a delivery receipt callback URL in your Vonage account dashboard. Vonage will POST status updates to that URL once the carrier confirms delivery. Use the message-id field in the response to correlate receipts to the original send.
Can I send SMS from an alphanumeric sender ID?
Yes — pass an 11-character alphanumeric string in the from parameter on POST /{format}. Some destination countries (including the United States and Canada) require a numeric long code or short code instead, so check the Vonage country support matrix before relying on alphanumeric for global traffic.
How do I send an SMS through Jentic?
Run pip install jentic, then use the Jentic search query 'send an SMS message' to discover POST /{format}. Load the schema, then execute with to, from, and text — Jentic resolves the api_key and api_secret from the vault. Sign up at https://app.jentic.com/sign-up.