Nexmo Numbers API
Browse all Nexmo APIs★ Only Publicly Available OpenAPI DocumentCommunicationsVoice TelephonyapiKey5 EndpointsREST
For Agents
Search Vonage's virtual number inventory, buy and cancel numbers, and configure their inbound SMS and voice webhooks programmatically.
Use for: I want to buy a US virtual number that supports SMS, Search for available toll-free numbers in the United Kingdom, List all the numbers my Nexmo account currently owns, Update the voice webhook URL for one of my numbers
Not supported: Does not send messages, place calls, or port existing numbers — use for virtual number provisioning and configuration only.
The Nexmo Numbers API lets developers search, buy, configure, and cancel virtual phone numbers across the countries Vonage supports. Each number can be wired to receive SMS or voice traffic and routed to a webhook, an application, or a SIP endpoint. The API exposes five operations covering inventory search, purchase, update, cancellation, and listing of currently owned numbers, and is the foundation that the SMS, Voice, and Messages APIs sit on top of.
Install Jentic One Beta
Connect the Numbers API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Numbers API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
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Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Numbers API.
Search Vonage's inventory for available virtual numbers by country and feature
Buy a virtual number in a specific country and assign it to your account
Update an owned number's inbound SMS and voice webhook configuration
Cancel a previously purchased number to stop monthly rental charges
List every virtual number currently owned by the account with status and capability
Use Cases
Patterns agents use Numbers API for, with concrete tasks.
★ Provisioning a new SMS sender
When an application needs a dedicated long-code or toll-free sender, the team calls /number/search to find available inventory in the target country, /number/buy to purchase it, and /number/update to wire the inbound webhook to their application. The whole provisioning flow takes three API calls and replaces a manual portal-based purchase.
Call GET /number/search?country=US&features=SMS, pick the first MSISDN, then POST /number/buy with country and msisdn
Inbound webhook reconfiguration
When a service migrates to a new domain or splits inbound SMS and voice handlers across services, operators call /number/update for each owned number to point moHttpUrl and voiceCallbackValue at the new endpoints. Doing this through the API rather than the portal keeps the configuration in version control and reproducible across environments.
POST /number/update with country, msisdn, and the new moHttpUrl pointing at https://api.example.com/inbound-sms
Number portfolio audit
Finance and operations teams call /account/numbers to list every number the account holds, including capabilities, country, and current webhook target. The output drives quarterly audits to cancel unused numbers, confirm two-region failover coverage, and reconcile the bill against the active inventory.
GET /account/numbers and group the response by country and feature to produce an inventory report
AI agent number provisioning via Jentic
An AI agent that orchestrates messaging campaigns can request a fresh sender programmatically through Jentic. The agent calls the search operation, picks an MSISDN that supports SMS in the target country, and executes the buy operation, all without ever holding the raw apiKey/apiSecret pair.
Search Jentic for 'buy a virtual phone number for sms', load /number/buy, and execute with country=US and the chosen msisdn
Key Endpoints
5 endpoints — the nexmo numbers api lets developers search, buy, configure, and cancel virtual phone numbers across the countries vonage supports.
METHOD
PATH
DESCRIPTION
GET
/account/numbers
List numbers owned by the account
GET
/number/search
Search available numbers in inventory
POST
/number/buy
Purchase a virtual number
POST
/number/update
Update webhook configuration on an owned number
POST
/number/cancel
Release a number and stop billing
GET
/account/numbers
List numbers owned by the account
GET
/number/search
Search available numbers in inventory
POST
/number/buy
Purchase a virtual number
POST
/number/update
Update webhook configuration on an owned number
POST
/number/cancel
Release a number and stop billing
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
Nexmo apiKey and apiSecret are stored encrypted in the Jentic vault. Agents receive scoped tokens, so the raw secret never enters the agent's prompt or logs.
Intent-based discovery
Agents search Jentic by intent (e.g. 'buy a virtual phone number for sms') and Jentic returns the matching POST /number/buy operation along with its input schema.
Time to first call
Direct integration: 1-2 days to handle search-buy-update flow plus webhook configuration. Through Jentic: under 30 minutes — search, load, execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Numbers API through Jentic.
What authentication does the Nexmo Numbers API use?
The Numbers API uses apiKey and apiSecret query parameters on every request to rest.nexmo.com. Through Jentic those credentials live in the encrypted vault, so an agent only ever sees a scoped access token and never the raw api_secret.
Can I search and buy a number in a single API call?
No — purchase is a two-step flow on purpose. First call GET /number/search with the country and feature filters, then call POST /number/buy with a specific msisdn from the result. Splitting the steps lets the application show inventory to a user before charging the account.
What are the rate limits for the Numbers API?
Vonage does not encode a numeric rate limit in the OpenAPI spec. The provisioning endpoints are not designed for high concurrency — bulk buys should be serialised, and /account/numbers should be cached rather than polled aggressively.
How do I update an inbound SMS webhook through Jentic?
Run pip install jentic, search for 'update inbound sms webhook for nexmo number', and Jentic returns POST /number/update. Execute with country, msisdn, and moHttpUrl set to your new endpoint, and Jentic returns the updated number record.
Can I get a refund for a number I just bought?
Calling POST /number/cancel stops the monthly rental immediately, but Vonage's commercial terms govern any pro-rata refund and that policy is not exposed via the API. Numbers purchased and cancelled in quick succession should be reconciled against your account's billing rules.
What features can I filter on when searching numbers?
The /number/search endpoint accepts a features query parameter that supports SMS, VOICE, and MMS, plus a type parameter for landline, mobile-lvn, and toll-free. Combine them with country and pattern to narrow inventory to exactly what your application needs.
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