Communications

An index and topic collection covering Communications Platform as a Service (CPaaS) and messaging-and-voice infrastructure APIs. This network gathers providers offering programmable SMS, MMS, voice, video, transactional and marketing email, chat, push notifications, in-app messaging, and deliverability services. It includes leading CPaaS platforms (Twilio, Vonage, MessageBird/Bird, Sinch, Plivo, Bandwidth, Telnyx, Infobip), transactional email providers (SendGrid, Mailgun, Postmark, Resend, SparkPost, Mailjet, MailerSend, Mailtrap), video and real-time platforms (Agora, Daily.co, LiveKit, Zoom, Dolby), push and in-app messaging (OneSignal, Pusher, Ably, PubNub, Sendbird, Airship, CleverTap), and notification orchestration layers (Courier, Knock, Customer.io, Braze, Iterable). It is distinct from the Bots topic, which covers conversational scripting and chatbot frameworks.

Communications is profiled on the APIs.io network. Tagged areas include CPaaS, SMS, MMS, Voice, and Email.

The Communications catalog on APIs.io includes 1 JSON-LD context.

Communications’ developer surface includes developer portal and 1 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

8.7/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-10-17 · rubric v0.24.0

0 APIs 8 Features 7 Use Cases

CPaaS SMS MMS Voice Email Push Notifications Video Chat Messaging Deliverability

Kin Score

Kin Score How this is scored →
scored 2026-10-17 · rubric v0.24.0

Composite quality — 8.7/100 · minimal

Contract Quality 3.1 / 21

Developer Ergonomics 1.6 / 17

Access Clarity 0.0 / 17

Operational Transparency 0.6 / 11

Contract Governance 0.0 / 10

Discoverability 4.1 / 9

Regulatory Posture 0.6 / 15

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Regulatory Posture applies to this provider. Its tags matched the Telecommunications regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/communications: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Features 8

Notable capabilities this provider offers.

Programmable SMS, MMS, and Voice

CPaaS providers expose programmable APIs for sending and receiving SMS and MMS messages, placing and routing voice calls, and managing phone number inventory across the global P...

Transactional and Marketing Email

Email APIs handle high-volume transactional sends, marketing campaigns, template rendering, list management, and deliverability monitoring through ESP infrastructure.

Real-Time Video and Audio

Video and real-time platforms expose APIs and SDKs for embedding live video calls, broadcasts, conferences, and low-latency audio rooms into applications.

Push Notifications and In-App Messaging

Push providers deliver native iOS and Android push notifications, web push, and in-app messages at scale across FCM, APNs, and proprietary delivery infrastructure.

Realtime Chat and Pub/Sub

Realtime APIs provide WebSocket-based pub/sub channels, chat rooms, presence, and message history for collaborative and social applications.

Notification Orchestration and Multi-Channel Delivery

Orchestration platforms unify SMS, email, push, chat, and in-app channels behind a single API with templating, preference management, and routing logic.

Deliverability and Reputation Management

Deliverability tooling covers IP warmup, SPF/DKIM/DMARC, bounce and spam handling, suppression lists, and engagement-based sender reputation analytics.

Number Provisioning and Verification

Communications APIs manage phone number purchase, porting, regulatory compliance, and verification flows like one-time passwords and silent network auth.

Scroll for all 8

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Communications Context

10 classes · 21 properties

JSON-LD

JSON Schema 2

Standalone JSON Schema definitions for this provider's data models.

DeliveryReceipt

12 properties

JSON SCHEMA

Message

16 properties

JSON SCHEMA

JSON Structure 2

JSON Structure definitions describing this provider's data shapes.

Communications Delivery Receipt Structure

12 properties

JSON STRUCTURE

Communications Message Structure

16 properties

JSON STRUCTURE

Examples 2

Example request and response payloads for these APIs.

Communications Delivery Receipt Example

10 fields

EXAMPLE

Communications Message Example

13 fields

EXAMPLE

Use Cases 7

What developers build with this provider.

Two-Factor Authentication and OTP Delivery

Applications use SMS, voice, and email APIs to deliver one-time passcodes and verification messages for login, signup, and high-risk action confirmation.

Transactional Notifications

Platforms send order confirmations, shipping updates, password resets, and account alerts through email, SMS, and push APIs as part of core product workflows.

Customer Engagement Campaigns

Marketing teams orchestrate multi-channel email, SMS, and push campaigns using providers like Braze, Iterable, Customer.io, and Klaviyo to drive retention and lifecycle messaging.

Live Video and Audio Embeds

Telehealth, education, and collaboration apps embed branded live video and audio experiences using Daily.co, Agora, LiveKit, Zoom SDKs, and Dolby.

Contact Center and Programmable Voice

Support and sales teams build programmable IVRs, click-to-call, call tracking, and conversational voice flows on Twilio, Vonage, Dialpad, and RingCentral.

Realtime Chat and Social Features

Apps add direct messaging, group chat, presence, and live commenting using Sendbird, Stream, PubNub, Ably, and Pusher.

Operational and Incident Alerting

Engineering and SRE teams page on-call staff and broadcast incident status via SMS, voice, push, and email through Knock, Courier, and CPaaS providers.

Scroll for all 7

Integrations 9

Pre-built integrations with other platforms and tools.

Twilio

Leading CPaaS provider offering programmable SMS, MMS, voice, video, email (via SendGrid), and verification APIs at global scale.

Vonage

CPaaS platform covering SMS, voice, video, verify, and conversation APIs across messaging channels including WhatsApp and Viber.

SendGrid

Transactional and marketing email API owned by Twilio, handling high-volume sends, templates, and deliverability.

MessageBird

Omnichannel CPaaS provider (Bird) offering SMS, voice, email, WhatsApp, and conversational messaging APIs across global carriers.

Sinch

Global CPaaS platform delivering SMS, voice, email (Mailgun, Mailjet), verification, and conversational messaging APIs.

OneSignal

Push notification, in-app messaging, email, and SMS platform with a unified messaging API used by mobile and web applications.

Sendbird

In-app chat, messaging, and calls API powering customer support and social experiences inside mobile and web applications.

Daily.co

WebRTC-based video and audio API for embedding live calls, broadcasts, and recording into web and mobile applications.

Mailgun

Transactional email and email validation API focused on deliverability for developers and high-volume senders.

Scroll for all 9

Resources

Get Started 1

Portal, sign-up, and the first successful call

Portal

Portal

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Source (apis.yml)

aid: communications
name: Communications
description: An index and topic collection covering Communications Platform as a Service (CPaaS) and messaging-and-voice infrastructure
  APIs. This network gathers providers offering programmable SMS, MMS, voice, video, transactional and marketing email, chat,
  push notifications, in-app messaging, and deliverability services. It includes leading CPaaS platforms (Twilio, Vonage,
  MessageBird/Bird, Sinch, Plivo, Bandwidth, Telnyx, Infobip), transactional email providers (SendGrid, Mailgun, Postmark,
  Resend, SparkPost, Mailjet, MailerSend, Mailtrap), video and real-time platforms (Agora, Daily.co, LiveKit, Zoom, Dolby),
  push and in-app messaging (OneSignal, Pusher, Ably, PubNub, Sendbird, Airship, CleverTap), and notification orchestration
  layers (Courier, Knock, Customer.io, Braze, Iterable). It is distinct from the Bots topic, which covers conversational scripting
  and chatbot frameworks.
type: Index
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
- CPaaS
- SMS
- MMS
- Voice
- Email
- Push Notifications
- Video
- Chat
- Messaging
- Deliverability
url: https://raw.githubusercontent.com/api-evangelist/communications/refs/heads/main/apis.yml
created: '2026-05-19'
modified: '2026-05-19'
specificationVersion: '0.19'
apis: []
network:
- name: Ably
  url: https://raw.githubusercontent.com/api-evangelist/ably/refs/heads/main/apis.yml
- name: Aircall
  url: https://raw.githubusercontent.com/api-evangelist/aircall/refs/heads/main/apis.yml
- name: Airship
  url: https://raw.githubusercontent.com/api-evangelist/airship/refs/heads/main/apis.yml
- name: Amazon Pinpoint
  url: https://raw.githubusercontent.com/api-evangelist/amazon-pinpoint/refs/heads/main/apis.yml
- name: Amazon SES
  url: https://raw.githubusercontent.com/api-evangelist/amazon-ses/refs/heads/main/apis.yml
- name: Amazon SNS
  url: https://raw.githubusercontent.com/api-evangelist/amazon-sns/refs/heads/main/apis.yml
- name: api.video
  url: https://raw.githubusercontent.com/api-evangelist/api-video/refs/heads/main/apis.yml
- name: Bandwidth
  url: https://raw.githubusercontent.com/api-evangelist/bandwidth/refs/heads/main/apis.yml
- name: Braze
  url: https://raw.githubusercontent.com/api-evangelist/braze/refs/heads/main/apis.yml
- name: CallRail
  url: https://raw.githubusercontent.com/api-evangelist/callrail/refs/heads/main/apis.yml
- name: CleverTap
  url: https://raw.githubusercontent.com/api-evangelist/clevertap/refs/heads/main/apis.yml
- name: ClickSend SMS
  url: https://raw.githubusercontent.com/api-evangelist/clicksend-sms/refs/heads/main/apis.yml
- name: Courier
  url: https://raw.githubusercontent.com/api-evangelist/courier/refs/heads/main/apis.yml
- name: Crisp
  url: https://raw.githubusercontent.com/api-evangelist/crisp/refs/heads/main/apis.yml
- name: Customer.io
  url: https://raw.githubusercontent.com/api-evangelist/customer-io/refs/heads/main/apis.yml
- name: Daily.co
  url: https://raw.githubusercontent.com/api-evangelist/daily-co/refs/heads/main/apis.yml
- name: Dialpad
  url: https://raw.githubusercontent.com/api-evangelist/dialpad/refs/heads/main/apis.yml
- name: Dolby
  url: https://raw.githubusercontent.com/api-evangelist/dolby/refs/heads/main/apis.yml
- name: Iterable
  url: https://raw.githubusercontent.com/api-evangelist/iterable/refs/heads/main/apis.yml
- name: JustCall
  url: https://raw.githubusercontent.com/api-evangelist/justcall/refs/heads/main/apis.yml
- name: Klaviyo
  url: https://raw.githubusercontent.com/api-evangelist/klaviyo/refs/heads/main/apis.yml
- name: Knock
  url: https://raw.githubusercontent.com/api-evangelist/knock/refs/heads/main/apis.yml
- name: LiveKit
  url: https://raw.githubusercontent.com/api-evangelist/livekit/refs/heads/main/apis.yml
- name: Loops
  url: https://raw.githubusercontent.com/api-evangelist/loops/refs/heads/main/apis.yml
- name: Mailchimp
  url: https://raw.githubusercontent.com/api-evangelist/mailchimp/refs/heads/main/apis.yml
- name: MailerLite
  url: https://raw.githubusercontent.com/api-evangelist/mailerlite/refs/heads/main/apis.yml
- name: MailerSend
  url: https://raw.githubusercontent.com/api-evangelist/mailersend/refs/heads/main/apis.yml
- name: Mailgun
  url: https://raw.githubusercontent.com/api-evangelist/mailgun/refs/heads/main/apis.yml
- name: Mailjet
  url: https://raw.githubusercontent.com/api-evangelist/mailjet/refs/heads/main/apis.yml
- name: Mailtrap
  url: https://raw.githubusercontent.com/api-evangelist/mailtrap/refs/heads/main/apis.yml
- name: MessageBird
  url: https://raw.githubusercontent.com/api-evangelist/messagebird/refs/heads/main/apis.yml
- name: Mux
  url: https://raw.githubusercontent.com/api-evangelist/mux/refs/heads/main/apis.yml
- name: OneSignal
  url: https://raw.githubusercontent.com/api-evangelist/onesignal/refs/heads/main/apis.yml
- name: Plivo
  url: https://raw.githubusercontent.com/api-evangelist/plivo/refs/heads/main/apis.yml
- name: Postmark
  url: https://raw.githubusercontent.com/api-evangelist/postmark/refs/heads/main/apis.yml
- name: PubNub
  url: https://raw.githubusercontent.com/api-evangelist/pubnub/refs/heads/main/apis.yml
- name: Pusher
  url: https://raw.githubusercontent.com/api-evangelist/pusher/refs/heads/main/apis.yml
- name: Resend
  url: https://raw.githubusercontent.com/api-evangelist/resend/refs/heads/main/apis.yml
- name: RingCentral
  url: https://raw.githubusercontent.com/api-evangelist/ringcentral/refs/heads/main/apis.yml
- name: Sendbird
  url: https://raw.githubusercontent.com/api-evangelist/sendbird/refs/heads/main/apis.yml
- name: SendGrid
  url: https://raw.githubusercontent.com/api-evangelist/sendgrid/refs/heads/main/apis.yml
- name: Sinch
  url: https://raw.githubusercontent.com/api-evangelist/sinch/refs/heads/main/apis.yml
- name: Stream
  url: https://raw.githubusercontent.com/api-evangelist/stream-io/refs/heads/main/apis.yml
- name: Telesign
  url: https://raw.githubusercontent.com/api-evangelist/telesign/refs/heads/main/apis.yml
- name: Telnyx
  url: https://raw.githubusercontent.com/api-evangelist/telnyx/refs/heads/main/apis.yml
- name: Twilio
  url: https://raw.githubusercontent.com/api-evangelist/twilio/refs/heads/main/apis.yml
- name: Vonage
  url: https://raw.githubusercontent.com/api-evangelist/vonage/refs/heads/main/apis.yml
- name: Zoom
  url: https://raw.githubusercontent.com/api-evangelist/zoom/refs/heads/main/apis.yml
common:
- type: Portal
  url: https://apievangelist.com
- type: GitHubOrganization
  url: https://github.com/api-evangelist
- type: Features
  data:
  - name: Programmable SMS, MMS, and Voice
    description: CPaaS providers expose programmable APIs for sending and receiving SMS and MMS messages, placing and routing
      voice calls, and managing phone number inventory across the global PSTN.
  - name: Transactional and Marketing Email
    description: Email APIs handle high-volume transactional sends, marketing campaigns, template rendering, list management,
      and deliverability monitoring through ESP infrastructure.
  - name: Real-Time Video and Audio
    description: Video and real-time platforms expose APIs and SDKs for embedding live video calls, broadcasts, conferences,
      and low-latency audio rooms into applications.
  - name: Push Notifications and In-App Messaging
    description: Push providers deliver native iOS and Android push notifications, web push, and in-app messages at scale
      across FCM, APNs, and proprietary delivery infrastructure.
  - name: Realtime Chat and Pub/Sub
    description: Realtime APIs provide WebSocket-based pub/sub channels, chat rooms, presence, and message history for collaborative
      and social applications.
  - name: Notification Orchestration and Multi-Channel Delivery
    description: Orchestration platforms unify SMS, email, push, chat, and in-app channels behind a single API with templating,
      preference management, and routing logic.
  - name: Deliverability and Reputation Management
    description: Deliverability tooling covers IP warmup, SPF/DKIM/DMARC, bounce and spam handling, suppression lists, and
      engagement-based sender reputation analytics.
  - name: Number Provisioning and Verification
    description: Communications APIs manage phone number purchase, porting, regulatory compliance, and verification flows
      like one-time passwords and silent network auth.
- type: UseCases
  data:
  - name: Two-Factor Authentication and OTP Delivery
    description: Applications use SMS, voice, and email APIs to deliver one-time passcodes and verification messages for login,
      signup, and high-risk action confirmation.
  - name: Transactional Notifications
    description: Platforms send order confirmations, shipping updates, password resets, and account alerts through email,
      SMS, and push APIs as part of core product workflows.
  - name: Customer Engagement Campaigns
    description: Marketing teams orchestrate multi-channel email, SMS, and push campaigns using providers like Braze, Iterable,
      Customer.io, and Klaviyo to drive retention and lifecycle messaging.
  - name: Live Video and Audio Embeds
    description: Telehealth, education, and collaboration apps embed branded live video and audio experiences using Daily.co,
      Agora, LiveKit, Zoom SDKs, and Dolby.
  - name: Contact Center and Programmable Voice
    description: Support and sales teams build programmable IVRs, click-to-call, call tracking, and conversational voice flows
      on Twilio, Vonage, Dialpad, and RingCentral.
  - name: Realtime Chat and Social Features
    description: Apps add direct messaging, group chat, presence, and live commenting using Sendbird, Stream, PubNub, Ably,
      and Pusher.
  - name: Operational and Incident Alerting
    description: Engineering and SRE teams page on-call staff and broadcast incident status via SMS, voice, push, and email
      through Knock, Courier, and CPaaS providers.
- type: Integrations
  data:
  - name: Twilio
    description: Leading CPaaS provider offering programmable SMS, MMS, voice, video, email (via SendGrid), and verification
      APIs at global scale.
  - name: Vonage
    description: CPaaS platform covering SMS, voice, video, verify, and conversation APIs across messaging channels including
      WhatsApp and Viber.
  - name: SendGrid
    description: Transactional and marketing email API owned by Twilio, handling high-volume sends, templates, and deliverability.
  - name: MessageBird
    description: Omnichannel CPaaS provider (Bird) offering SMS, voice, email, WhatsApp, and conversational messaging APIs
      across global carriers.
  - name: Sinch
    description: Global CPaaS platform delivering SMS, voice, email (Mailgun, Mailjet), verification, and conversational messaging
      APIs.
  - name: OneSignal
    description: Push notification, in-app messaging, email, and SMS platform with a unified messaging API used by mobile
      and web applications.
  - name: Sendbird
    description: In-app chat, messaging, and calls API powering customer support and social experiences inside mobile and
      web applications.
  - name: Daily.co
    description: WebRTC-based video and audio API for embedding live calls, broadcasts, and recording into web and mobile
      applications.
  - name: Mailgun
    description: Transactional email and email validation API focused on deliverability for developers and high-volume senders.
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
humanURL: https://apievangelist.com

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