NumLookupAPI
★ Only Publicly Available OpenAPI DocumentData EnrichmentContact EnrichmentapiKey2 EndpointsREST
For Agents
Validate and enrich a phone number with carrier, line type, and country information from a single GET call.
Use for: Validate a phone number and return its country and carrier, Check whether a phone number is a mobile or VoIP line, Get the country code for an international phone number, Find out if a submitted contact's phone is reachable
Not supported: Does not send SMS, place calls, or perform identity verification — use for phone-number validation and carrier enrichment only.
Jentic publishes the only available OpenAPI specification for NumLookupAPI, keeping it validated and agent-ready. NumLookupAPI is a phone-number validation and enrichment service that returns carrier, line type, country, and location data for numbers across 230+ countries. The API exposes a single validation endpoint plus a status check, designed for low-latency lookups at form submission or during contact enrichment. It is used by lead-quality teams, KYC pipelines, and SMS senders that need to filter invalid or expensive routes before sending.
Install Jentic One Beta
Connect the NumLookupAPI to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the NumLookupAPI, 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.
1
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 NumLookupAPI API.
Validate a phone number and return its carrier and line type
Identify the country of origin for an international phone number
Filter form submissions for invalid or non-mobile phone numbers
Detect VoIP and landline numbers before sending SMS
Confirm the API is healthy via the status endpoint
Enrich CRM contact records with validated phone metadata
Use Cases
Patterns agents use NumLookupAPI API for, with concrete tasks.
★ Form Validation at Lead Capture
Marketing forms call GET /v1/validate/{phone_number} when a user submits a phone number to confirm it is real and reachable. Invalid or VoIP entries are flagged before the lead lands in the CRM, reducing wasted SDR time and SMS spend. Integration is a single GET call with the API key.
Call GET /v1/validate/{phone_number} for the submitted number and reject the lead if valid is false
SMS Routing Optimisation
SMS senders look up line type before queuing a campaign so VoIP and landline numbers do not consume mobile-only routes. The carrier and line-type fields returned by /v1/validate let the sender route or skip messages and save on per-message charges.
Call GET /v1/validate/{phone_number} for each recipient and filter out line types other than mobile before sending SMS
Agent-Driven Contact Enrichment
An AI agent enriching new CRM contacts validates each phone number through Jentic before saving. The agent searches for 'validate phone number', loads the GET /v1/validate/{phone_number} schema, and writes the carrier and country back to the contact record.
Search Jentic for 'validate a phone number', load the schema for GET /v1/validate/{phone_number}, and execute for each new lead
Key Endpoints
2 endpoints — jentic publishes the only available openapi specification for numlookupapi, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
GET
/v1/validate/{phone_number}
Validate and enrich a phone number
GET
/v1/status
Check API status
GET
/v1/validate/{phone_number}
Validate and enrich a phone number
GET
/v1/status
Check API status
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
NumLookupAPI keys are stored encrypted in the Jentic vault. Agents call the validation endpoint with scoped tokens, so the raw key never appears in prompts or logs.
Intent-based discovery
Agents search Jentic with intents like 'validate a phone number' or 'detect VoIP line' and Jentic returns the matching NumLookupAPI operation with its schema.
Time to first call
Direct NumLookupAPI integration: a few hours for auth and parsing. Through Jentic: under 15 minutes — search, load, execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using NumLookupAPI API through Jentic.
Why is there no official OpenAPI spec for NumLookupAPI?
NumLookupAPI does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call NumLookupAPI 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 NumLookupAPI use?
The spec declares an apiKey scheme. Through Jentic the API key is stored encrypted in the vault and injected at execution, so the agent never holds the raw key in its prompt or logs.
Can I detect whether a number is a mobile or VoIP line?
Yes. The response from GET /v1/validate/{phone_number} includes the line type field, which lets you distinguish mobile, landline, and VoIP numbers before routing SMS or making a call.
How do I validate a phone number through Jentic?
Search Jentic for 'validate a phone number', load the schema for GET /v1/validate/{phone_number}, and execute with the number you want to check. Jentic returns the parsed validation payload with carrier and country.
What are the rate limits for NumLookupAPI?
Rate limits are not declared in the OpenAPI spec. NumLookupAPI applies plan-based monthly request limits in production; check your dashboard for the quota that applies to your key and tier.
How do I check that the NumLookupAPI service is healthy?
Call GET /v1/status to confirm the service is responsive. Use this in scheduled health checks or as a cheap pre-flight before running a high-volume validation batch.
GET STARTED