Nexmo Conversion API
Browse all Nexmo APIs52
AI ReadinessFoundational (C-)52/100
Community OpenAPI document · agent-readyCommunicationsSms MessagingapiKey2 EndpointsREST
Know of an official OpenAPI document? Contribute it →
For Agents
Report SMS and voice 2FA conversion outcomes back to Nexmo so the platform can tune routing and reliability for future verification traffic.
Use for: I want to report a successful SMS 2FA verification back to Nexmo, Send conversion data for a voice OTP that the user completed, Confirm that a verification SMS message-id resulted in a real conversion, Mark a Nexmo voice call as not converted when the code was never entered
Not supported: Does not send messages, verify codes, or manage phone numbers - use for posting 2FA conversion outcomes back to Nexmo only.
The Nexmo Conversion API lets developers report back to Vonage whether a 2FA SMS or voice verification message was actually delivered and acted on by the recipient. Feeding this conversion signal back into the Nexmo platform helps optimise carrier routes, improve future delivery reliability, and surface fraudulent traffic patterns. The API exposes two simple POST endpoints, one for SMS and one for voice, each accepting a message-id, a delivered flag, and an optional timestamp.
Install Jentic One Beta
Connect the Nexmo Conversion API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Nexmo Conversion 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.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fnexmo.com%2Fnexmo-conversion-api" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fnexmo.com%2Fnexmo-conversion-api" | 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 Nexmo Conversion API.
Report whether a 2FA SMS code was successfully entered by the end user
Report whether a 2FA voice call code was successfully entered by the end user
Attach a delivery timestamp to each conversion record for accurate latency tracking
Tag SMS message-ids returned by the SMS API with conversion status to improve routing
Tag voice call-ids returned by the Voice API with conversion status to improve routing
Use Cases
Patterns agents use Nexmo Conversion API for, with concrete tasks.
★ 2FA SMS conversion feedback
When an application sends a 2FA code via the Nexmo SMS API, the Conversion API closes the loop by reporting whether the user actually entered the code. Posting a delivered=true or delivered=false flag against the original message-id lets Nexmo learn which carrier routes deliver real conversions versus silent failures, which directly improves future deliverability.
POST /sms with message-id from a previously sent verification SMS and delivered=true once the user submits the correct code
Voice OTP conversion tracking
Applications that deliver one-time passwords by automated voice call can report whether the recipient successfully entered the spoken code. The /voice endpoint accepts the call-id returned by the Voice API along with a delivered flag, allowing Nexmo to discriminate between answered-and-converted, answered-but-abandoned, and undelivered call outcomes.
POST /voice with the call-id from a Voice API verification call, delivered=true, and the timestamp the user completed the code
Routing optimisation feedback loop
Operations and trust teams send batch conversion updates back to Nexmo at the end of each verification session so the platform can recalculate carrier-route quality. Reporting both successful and failed conversions, rather than only successes, gives the routing engine balanced signal and reduces silent failure rates over time.
Loop through yesterday's verification messages and POST /sms or /voice for each with the appropriate delivered flag and timestamp
AI agent posting verification outcomes via Jentic
An AI agent that orchestrates a sign-up flow can call the Nexmo Conversion API through Jentic immediately after the user completes verification. Jentic handles the API key and secret, so the agent simply searches for the conversion operation, supplies the message-id and delivered flag, and Jentic executes the POST against api.nexmo.com/conversions.
Search Jentic for 'report sms 2fa conversion to nexmo', load the /sms operation, and execute with message-id=MESSAGE_ID and delivered=true
Key Endpoints
2 endpoints — the nexmo conversion api lets developers report back to vonage whether a 2fa sms or voice verification message was actually delivered and acted on by the recipient.
METHOD
PATH
DESCRIPTION
POST
/sms
Report SMS 2FA conversion outcome
POST
/voice
Report voice OTP conversion outcome
POST
/sms
Report SMS 2FA conversion outcome
POST
/voice
Report voice OTP conversion outcome
Jentic AI Readiness Score
This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.
N
Nexmo Conversion API
- Foundational (C-)52/100
100
Foundational Compliance75
Developer Experience & Jentic Compatibility56
AI-Readiness & Agent Experience94
Agent Usability15
Security100
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.0
Show dimension breakdown
100
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: A+Signals: 4
99%
Lint Results
Aggregated quality score from linter diagnostics, weighted by severity.
100%
Resolution Completeness
Percentage of `$ref` references that resolve successfully.
100%
Specification Validity
Checks whether the API description parses successfully and conforms to its declared specification (e.g., OpenAPI).
100%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
75
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: A-Signals: 4
50%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
50%
Response Coverage
Percentage of operations with complete response definitions (success, client error, server error).
100%
Tooling Readiness
Health of API ingestion, bundling, and resolution within Jentic pipelines.
56
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: CSignals: 4
75%
Description Coverage
Coverage of descriptions across API elements.
0%
Error Standardization
Coverage of RFC 9457 Problem Details for error responses.
100%
OperationId Quality
Coverage, uniqueness, and casing consistency of operationIds for AI inference.
50%
Summary Coverage
Coverage of summaries across operations/tags/info.
94
Agent Usability
Functional utility, complexity comfort, and AI orchestration readiness.
Grade: A+Signals: 1
94%
Complexity Comfort
Agent comfort level based on API operational and structural complexity.
15
Security
Trust, risk posture, and security compliance.
Grade: FSignals: 1
15%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
100
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: A+Signals: 1
100%
Descriptive Richness
Clarity and depth of descriptions across API elements.
Score it yourself
Every API in the directory is allowlisted, so you can re-score it with no key required.
npx @jentic/api-scorecard-cli score <openapi-url>Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Nexmo Conversion API by hand means appending your api_key and api_secret to every query string and targeting the api.nexmo.com/conversions host for each conversion post. Through Jentic you install once, import the Conversion API from the API Directory, store the api_key and api_secret once, and your agent calls it.
Permission scoping
The Conversion API carries the message id in the request body, so scoping is by operation rather than by resource: limit the agent to the operations it needs, such as posting an SMS conversion or a voice conversion. You credit it only with the conversion-reporting calls it requires, and nothing beyond that set runs.
Credential isolation
Your Nexmo api_key and api_secret are stored once, encrypted, by your own Jentic One instance and injected at execution time. They never enter the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'report an SMS 2FA conversion', and Jentic returns the matching POST /sms or POST /voice operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Nexmo Conversion API through Jentic.
What authentication does the Nexmo Conversion API use?
The Conversion API uses Nexmo's standard apiKey and apiSecret query parameters, with optional apiSig for signed requests. Through Jentic these credentials live in the encrypted vault, so the agent only sees a scoped token and never the raw api_key or api_secret.
Can I report both SMS and voice conversions with the same API?
Yes. POST /sms accepts message-ids returned by the Nexmo SMS API and POST /voice accepts call-ids returned by the Nexmo Voice API. Both endpoints share the same delivered flag and timestamp parameters, so a single integration covers both verification channels.
What are the rate limits for the Nexmo Conversion API?
Vonage does not publish a hard per-second rate limit for the Conversion API and the OpenAPI spec does not encode one. In practice the endpoint is designed to absorb post-hoc batch reporting, so spreading conversion posts over the same window in which messages were sent is the safest pattern.
How do I report a converted SMS through Jentic?
Run pip install jentic, search for 'report sms 2fa conversion to nexmo', load the POST /sms operation, and execute with message-id, delivered=true, and an optional timestamp. Jentic injects the apiKey credentials and returns the Nexmo response.
Is the Nexmo Conversion API free?
Reporting conversion data does not incur a per-call charge from Vonage; the cost sits with the underlying SMS or voice verification message you originally sent. Only customers already using the Nexmo SMS or Voice APIs would have message-ids to report against.
Should I report failed conversions as well as successful ones?
Yes. Sending only delivered=true skews the routing engine because Nexmo cannot distinguish silent failures from messages you simply never followed up on. Posting delivered=false for OTPs that were never entered gives the platform balanced signal.
Can I limit what my agent is allowed to do with the Nexmo Conversion API?
Yes. Because Jentic One is self-hosted, you set the rules that decide which operations and credentials your agent may use. The Conversion API scopes by operation rather than resource, so you can grant the agent only the calls it needs, such as posting an SMS conversion to POST /sms or a voice conversion to POST /voice, and withhold either endpoint. Anything outside the operations you credit it with does not run.
GET STARTED