Ranked by the provider's API Evangelist rating — the Kin Score is scored per provider, not per API, so every API of a provider shares its band. How the rating works →

Exemplar 13 Complete, well-documented, and agent-ready

Customer.io Track APIThe Customer.io Track API allows developers to send behavioral data and customer profile information into C...89.3 Salesforce Interaction Service APIThe Salesforce Interaction Service API enables automation and customization of the Bring Your Own Channel (...87.5 Salesforce Messaging APIOperations for creating and tracking email and SMS message sends, including triggered sends and transaction...87.5 HubSpot Engagement Communications APIThe communications API allows you to log WhatsApp, LinkedIn, or SMS messages to CRM record timelines. You c...87.1 Elation Health Messaging APISecure direct messaging83.7 Ada Conversations APIRead and manage conversations handled by the Ada AI Agent across all supported channels.83.2 Transactional Messaging APISpecialized API for sending triggered, transactional messages including order confirmations, password reset...82.6 Appwrite Messaging APIThe Messaging service allows you to send messages to any provider type (SMTP, push notification, SMS, etc.)...80.5 Microsoft Azure Event Grid APIAzure Event Grid is a fully managed event routing service that enables developers to build event-driven arc...73.3 Orange Business Messaging Pro Cameroon APICameroon-specific A2P messaging platform for enterprise SMS, USSD, and rich messaging deliveries to Orange ...70.1 Orange Business SMS Middle East and Africa APIA2P SMS delivery API for Orange Middle East and Africa footprint. Supports transactional, OTP, and marketin...70.1 Service Cloud Live Agent APIReal-time chat with customers over the Live Agent REST surface. Superseded for new builds by Messaging for ...68.6 HERE Stream API v2HERE Stream API v2 — 7 operation(s) across 6 path(s), OpenAPI 3.0.1 version 2.1.2, harvested verbatim from ...68.4

Strong 42 Solid coverage with minor gaps

Facebook Messenger Platform APIBuild conversational experiences on the Messenger platform. The Messenger Platform API enables businesses t...65.7 Facebook WhatsApp Business Platform APISend and receive messages, manage business profiles, and automate customer communications through the Whats...65.7 Slack Incoming Webhooks APISlack Incoming Webhooks provide a simple way to post messages from external sources into Slack. Creating an...65.6 Instagram Messaging APIThe Messenger API support for Instagram consolidates Instagram and Facebook Page messaging into a unified p...65.4 Cloudflare Email Routing APIThe Cloudflare Email Routing API enables developers to create and manage custom email addresses and routing...65.1 Swisscom Receive SMS APIInbound SMS API that exposes message inboxes so applications can receive texts from customers and build two...64.9 Swisscom Text Messaging (SMS) APIApplication-to-person SMS sending over the Swisscom messaging infrastructure with onward delivery to 260+ o...64.9 CleverTap Campaign APIProgrammatically create and manage push, email, SMS, web, and in-app campaigns and retrieve message status ...64.1 Weave Messaging APITwo-way SMS/text messaging with patients.64.1 Dify Chat Messages APIOperations related to chat messages and interactions. 3 operation(s) from the Dify Service API.64.0 Dify Conversations APIOperations related to managing conversations. 6 operation(s) from the Dify Service API.64.0 Unified.to messaging APIThe messaging API from Unified.to — 5 operation(s) for messaging.63.8 Dotdigital Messaging APIThe Messaging API from Dotdigital — 2 operation(s) for messaging.62.8 KPN Email-to-SMS APIConverts inbound email into SMS messages delivered over the KPN network. Documented on the KPN Developer po...62.4 KPN SMS Campaigns APISend and schedule bulk SMS campaigns over the KPN network. Documented on the KPN Developer portal; no publi...62.4 Sprout Social APIThe Sprout Social Public API provides programmatic access to publishing, analytics, messaging, listening, a...62.0 Zendesk Sunshine Conversations APIThe Zendesk Sunshine Conversations API is a messaging platform that lets you unify messages from every chan...61.1 ServiceNow Email APIThe ServiceNow Email API provides REST endpoints for sending email messages from the Now Platform. It allow...60.7 Nash Messaging APIMessaging60.2 OCI Email Delivery APIREST APIs for sending high-volume and application-generated emails through Oracle Cloud Infrastructure, wit...60.2 OCI Notifications APIPublish and subscribe messaging service for setting up communication channels using topics and subscription...60.2 OCI Queue APIServerless messaging service for decoupling application components with reliable message delivery, supporti...60.2 OCI Streaming APIManaged messaging service for ingesting and consuming high-volume data streams in real time, compatible wit...60.2 IBM Cloud Event NotificationsRoute event notifications from IBM Cloud services to communication channels such as email, SMS, webhooks, a...60.0 IBM Event StreamsFully managed Apache Kafka service for high-throughput event streaming, event ingestion, and event stream d...60.0 Wunderkind Text Message APIRESTful endpoints for delivering text messages from platforms external to the Wunderkind ecosystem (ESP, CD...59.7 Azure Event Hubs Messaging APIEvent-driven messaging API for publishing and consuming events via AMQP 1.0, Kafka, and HTTPS protocols. Su...58.6 Community messaging APIThe messaging API from Community — 1 operation(s) for messaging.58.2 Genesys Messaging APIMessaging58.1 Amazon Q Developer in Chat Applications APIAPI for Amazon Q Developer in chat applications, which enables integration of Amazon Q Developer capabiliti...57.6 Pabbly Chatflow APIREST API for Pabbly Chatflow, a WhatsApp Business messaging platform. 33 documented operations covering 18 ...57.5 Red Hat Streams for Apache Kafka Bridge APIHTTP bridge API for producing and consuming messages to Apache Kafka topics without requiring a native Kafk...57.5 Instagram Messaging APISend and receive messages on Instagram using the Messenger Platform, enabling customer service and automate...56.7 Messenger Platform APIBuild messaging experiences on Facebook Messenger including chatbots, rich media messages, and customer ser...56.7 WhatsApp Business Management APIManage WhatsApp Business accounts, phone numbers, message templates, and business profiles programmatically.56.7 WhatsApp Cloud APISend and receive messages, manage phone numbers, and build messaging experiences on WhatsApp using Meta's c...56.7 RingCentral SMS APIThe SMS API from RingCentral — 2 operation(s) for sms.56.3 RingCentral Voicemail APIThe RingCentral Voicemail API enables retrieval, playback, and management of voicemail messages, including ...56.3 Lichess Messaging APIPrivate messages with other players. 55.9 Leanplum Messaging APIThe Messaging API from Leanplum — 3 operation(s) for messaging.55.5 Apple Push Notification Service (APNs)Send push notifications to iOS, macOS, watchOS, and tvOS devices.55.1 Route Mobile Messaging APISend template messages (marketing, utility, authentication) and session messages (text, media, interactive,...54.7

Developing 85 Usable, with meaningful gaps to close

Entergram API54.1 Zoho CliqThe Zoho Cliq REST API v2 allows developers to extend their web applications by programmatically managing c...54.1 Zoho MailThe Zoho Mail REST API allows developers to fetch email conversations and integrate Zoho Mail into applicat...54.1 Microsoft Teams Bot Framework APIAPI for building conversational bots that interact with users in Microsoft Teams through the Bot Framework.54.0 Whoosh Programmable Messaging APIWhoosh! is Totogi's Application-to-Person (A2P) messaging API, launched in September 2023 and positioned as...54.0 CloudGuard Inventory - AWS Application Integration APIAWS application-integration inventory - SNS topics, SQS queues and related messaging services.53.7 Zoom Mail APIThe Zoom Mail API enables developers to programmatically access and manage mailbox data including draft man...53.3 Zoom Team Chat APIThe Zoom Team Chat API enables developers to integrate messaging into applications and automate workflows w...53.3 Artera Messaging API (MAPI)Artera's outbound SMS API, marketed to health systems and Artera Marketplace vendors as the SendMessage API...52.8 Optus SMS Suite HTTPS APILegacy GET-based HTTPS interface for SMS integration, covering message sending, delivery receipts, and inbo...52.6 Optus SMS Suite MMS MM7 APIImplementation of the 3GPP MM7 SOAP protocol for sending and receiving MMS, carrying text, image, audio, vi...52.6 Optus SMS Suite REST Email APICompanion REST API to the SMS gateway for scheduling and sending plain-text transactional email over a sepa...52.6 Optus SMS Suite SMPP APIDirect SMSC connectivity over SMPP 3.3 and 3.4 with mandatory TLS, offering high-throughput binary messagin...52.6 Optus SMS Suite SOAP APIWSDL-described SOAP interface for SMS integration supporting custom source addressing, message classificati...52.6 Emotive Messaging APIThe Messaging API from Emotive — 1 operation(s) for messaging.52.1 Telia Bulk Messaging SMPP APISMPP v3.4-style binary protocol interface into the Telia Company Bulk Messaging Platform, reached over TLS ...51.9 Telia Bulk Messaging SMS Callback APIThe webhook half of Telia's Bulk Messaging REST surface. Customers must implement a Receive SMS (mobile ori...51.9 Telia Bulk Messaging SMS REST APIJSON REST API for submitting mobile-terminated SMS through the Telia Company Bulk Messaging Platform, with ...51.9 WeChat Mini Programs Server APIBackend HTTPS/JSON APIs that Mini Program operators call from their own servers to authenticate user sessio...51.9 WeChat Official Accounts APIHTTPS/JSON APIs for WeChat Official Accounts (Subscription Accounts and Service Accounts) — the publishing ...51.9 WeChat Work (WeCom) APIServer API for Enterprise WeChat / WeCom — Tencent's enterprise collaboration suite. All calls are HTTPS/JS...51.9 LSEG Messenger Bot SDKSDK for building intelligent, compliant messaging bots within the LSEG Messenger platform. Enables sending,...51.8 Messenger Side by Side APIAPI allowing external applications to connect with and pass information into LSEG Messenger. Requires user ...51.8 WhatsApp Flows APIAPI for creating structured, interactive forms and multi-step flows within WhatsApp conversations, enabling...51.4 WhatsApp On-Premises APIThe self-hosted version of the WhatsApp Business API that allowed businesses to run the API on their own in...51.4 MuleSoft Anypoint MQ APIThe Anypoint MQ API provides a cloud messaging service built on the Anypoint Platform for asynchronous mess...51.3 TPG Telecom Messaging Hub Contacts APIContacts Management API for the Vodafone Business Messaging Hub, providing CRUD over contacts, lists and cu...51.3 TPG Telecom Messaging Hub REST APIThe SMS/MMS REST API of the Vodafone Business Messaging Hub, listed on the product page as "Access to our R...51.3 Twitch Chat APIManage chat settings, emotes, badges, and announcements51.2 Vonage Conversations APIBuild multi-channel conversation experiences with threading across SMS, voice, and messaging channels. Mana...51.0 Gmail APISend and read email, manage drafts and labels, and handle mailbox settings.50.6 Google Chat APIBuild bots and integrations for Google Chat.50.6 Oracle Transactional Event Queues (TxEventQ)Kafka-compatible event streaming and message queuing built into Oracle Database.50.6 Hostaway Messaging APIUnified guest messaging across Airbnb, Vrbo, Booking.com, Expedia, email, SMS, and WhatsApp. Resources incl...50.5 phone-com-apiPhone.com v4 ("Phoenix") JSON REST API for managing accounts, extensions, devices, phone numbers, call rout...50.5 MoMo Business Page OpenAPIServer-to-server API for operating a MoMo Business Page: list and read managed pages, update page detail, i...50.4 Azure Service BusAzure Service Bus is a fully managed enterprise message broker with message queues and publish-subscribe to...50.3 ManyChat Sending APISend Dynamic Block content and trigger automations for a subscriber across Messenger, Instagram and WhatsAp...50.2 SAP Event Mesh APIMessaging APIs for event-driven architecture supporting AMQP, MQTT, and REST protocols.49.3 Google Chat APIThe Google Chat API enables developers to build Chat apps that bring services and resources into Google Cha...48.4 GP Connect Send Document FHIR APISend a PDF consultation summary or clinical document to a patient's registered GP practice. Used when a pat...47.5 StackOne Unified Messaging APIStackOne Unified Messaging API standardizes communication workflows across platforms, with consistent data ...46.9 Telegram Messaging APIMethods for sending messages and media46.8 IronMQ v3IronMQ is a high-performance hosted message queue that lets you pass messages and events between processes ...46.3 SAP Event Mesh APIThe SAP Event Mesh API provides access to the event brokering service within SAP Business Technology Platfo...46.2 SAP Integration Suite Advanced Event Mesh APIThe SAP Integration Suite Advanced Event Mesh (AEM) REST API provides management capabilities for event bro...46.2 Apache Kafka Messaging APIThe core Kafka messaging protocol for producing and consuming records to/from topics using the native Kafka...45.9 CommsHarbor APIREST/HTTP API (OpenAPI 3.1) for transactional email, deliverability, sending domains, permission-based mark...45.6 Workday Integration Messaging APIThe Messaging API from Workday Integration — 2 operation(s) for messaging.45.4 Cisco Webex APIREST API for Webex collaboration platform enabling messaging, meeting management, device control, and admin...45.3 Spring WebFlux WebSocketReactive WebSocket support for full-duplex, bidirectional communication in WebFlux applications. Provides W...45.3 TIBCO Messaging APIEnterprise messaging API supporting EMS (Enterprise Message Service) and FTL (Fast Transport Layer).44.7 AsyncAPI SpecificationThe AsyncAPI Specification is an open standard for describing asynchronous and event-driven APIs. It provid...44.4 SJTU Open APIThe university's own REST API platform (开放API), operated by the SJTU Network and Information Center at api....43.8 Trellix Data Exchange Layer (DXL) APIMessaging fabric API that enables real-time communication between security tools and data sharing across th...43.6 TU Berlin Matrix Homeserver (Client-Server API)TU Berlin runs its own Matrix homeserver for institutional messaging, with an Element web client at chat.tu...43.2 Telesign Messaging APISend and track SMS messages43.1 Message Exchange for Social Care and Health (MESH) APIExchange messages and data files between NHS organisations using MESH, the national messaging infrastructur...42.6 Bird Messaging APISend and receive messages across channels.42.5 NATS Messaging APIAsynchronous messaging API supporting core pub-sub, request-reply, queue groups, and JetStream persistent m...42.5 Jupyter Kernel Messaging ProtocolWebSocket-based messaging protocol for communication between Jupyter clients and computational kernels. Sup...42.3 Rokid Sprite Enterprise OpenAPIThe Rokid Glass3 / Sprite Enterprise cloud API. Device registration lookup and real-time telemetry, message...42.2 Plivo Message APISend and retrieve SMS, MMS, and WhatsApp messages.41.9 Plivo Powerpack APIThe Plivo Powerpack API creates and manages Powerpacks — pools of numbers that distribute outbound messagin...41.9 Sarj AI Developer API Messaging APIThe messaging API from Sarj AI Developer API — 8 operation(s) for messaging.41.5 Roblox Engine API Messaging APICross-server messaging service41.4 Signal Android SDKSignal-Android is the open-source Android client for the Signal encrypted messaging platform. It provides t...41.3 Signal Desktop SDKSignal-Desktop is the open-source desktop client for the Signal encrypted messaging platform, built with El...41.3 Signal iOS SDKSignal-iOS is the open-source iOS client for the Signal encrypted messaging platform. It delivers end-to-en...41.3 Signal Protocol SpecificationsThe Signal Protocol Specifications define the core cryptographic protocols that underpin Signal's end-to-en...41.3 China Mobile Internet Capability Open Platform中国移动互联网能力开放平台 at dev.10086.cn is the operator's application-facing capability marketplace, describing itsel...41.2 Chatfuel Broadcasting APIProgrammatically send messages and trigger flows/blocks to a specific bot user on Messenger, Instagram, or ...40.7 Chatwoot Client APIThe Client API is designed for building custom messaging interfaces for end users. Authenticates using inbo...40.7 Submittable Messaging APIMessage attachments.40.5 Whippy Messaging APISend SMS / MMS, email, and fax messages.40.5 Chatfuel Broadcasting APIHTTP API for sending any block or flow from a bot to a user via a POST request, including targeting users b...40.4 Pusher Channels APIPub/sub channels over WebSocket (client) and HTTP (server publish). Public, private, and presence channels ...40.1 SleekFlow Messaging APISend messages, files, and internal notes; check conversation windows.40.1 Veterans Affairs Messaging APIThe Messaging API from Veterans Affairs — 20 operation(s) for messaging.40.1 Kno2 Messaging APISEND surface - draft, populate, attach, and send messages.39.9 CloudEvents AMQP Protocol BindingThe AMQP protocol binding for CloudEvents defines how events are mapped to OASIS AMQP 1.0 messages. In stru...39.6 CloudEvents Kafka Protocol BindingThe Kafka protocol binding for CloudEvents defines how events are mapped to Apache Kafka messages. It speci...39.6 CloudEvents NATS Protocol BindingThe NATS protocol binding for CloudEvents defines how events are mapped to NATS messages. It enables CloudE...39.6 McAfee Data Exchange Layer (DXL) APIMessaging fabric for real-time security data exchange and integration.39.4 IBM MQ JMS APIJava Message Service API for IBM MQ.39.3

Thin 77 Limited public surface area

Burner APIOAuth 2.0 REST API for programmatic access to Burner line management, messaging (SMS/MMS) and configuration...39.2 Backendless Messaging APIPublish-subscribe messaging, push notifications, and email.39.0 KrakenD Async AgentThe KrakenD Async Agent enables event-driven API consumption by connecting KrakenD to message brokers and e...39.0 Lodgify Messaging APIGuest conversation threads and messages.38.5 The Interaction Company Of California Messaging APISend messages to Poke programmatically.38.3 Appgain Notify APIThe messaging send service. A single POST /{projectId}/send endpoint whose channel is selected by the top-l...38.2 Appgain OmniChannel Messaging APIREST API for sending multi-channel campaigns (rich push notifications, email, SMS, web push), creating smar...38.2 FedNow ISO 20022 Message SpecificationsThe core scheme messaging surface of the FedNow Service. FedNow is ISO 20022 native and defines message typ...38.2 Smoobu Messaging APIReservation messages and unified inbox threads.38.0 Casey's StoreMessagingApiAllows services running in a Casey's store to receive messages from external sources. Registers store agent...37.9 Roblox Open Cloud Messaging ServiceThe Messaging Service Open Cloud API publishes messages to a topic that running game servers can subscribe ...37.5 Atom Customers APIREST service for managing the customer (cliente) records behind Atom's WhatsApp conversations. The provider...37.3 Atom WhatsApp Templates APIREST service for sending pre-approved WhatsApp template messages from an account's official WhatsApp number...37.3 Botpress Chat APIWebhook-based REST API for sending and receiving chat messages with deployed Botpress bots. Endpoint patter...37.2 FAU Matrix HomeserverFAU operates a Matrix homeserver — Synapse 1.159.0 at matrix.fau.de — with a hosted Element web client at c...37.1 Application Research Messaging APIMessaging portable resource operations36.4 Mattermost REST APIREST API v4 for managing users, teams, channels, posts, threads, files, integrations, plugins, webhooks, sl...36.2 Mattermost WebSocket APIReal-time WebSocket event stream for Mattermost v4. Clients connect to /api/v4/websocket, authenticate via ...36.2 XMTP Android SDKNative Kotlin SDK for integrating XMTP encrypted messaging into Android applications. Supports wallet-based...36.0 XMTP iOS SDKNative Swift SDK for integrating XMTP encrypted messaging into iOS applications. Provides wallet-based auth...36.0 XMTP JavaScript/TypeScript SDKClient SDK for browsers and Node.js enabling applications to send and receive end-to-end encrypted messages...36.0 XMTP Network gRPC APICore gRPC-based API for the XMTP decentralized messaging network. Provides operations for sending and retri...36.0 ABC Trainerize Messaging APISend in-app messages and upload attachments / meal-plan PDFs to clients.35.9 Telnyx Messaging APIThe Messaging API from Telnyx — 8 operation(s) for messaging.35.6 Apache ActiveMQ BrokerThe ActiveMQ Classic broker provides high-performance asynchronous messaging through multiple protocol inte...35.5 Photon Chat APIA separately billed Photon Cloud service (its own AppId type) for text messaging, presence, and friend list...35.2 CleanCloud Messaging APICustomer/store messaging and push notification tokens.35.1 Vault12 Zax Cryptographic Relay APIOpen-source NaCl-based cryptographic relay operated as asynchronous "dead drops" for end-to-end-encrypted d...34.9 Chert Messaging APIProgrammatic send/receive/route over iMessage — 1:1 and group chats, attachments, rich links, tapbacks, typ...34.5 Spring Integration AMQP AdapterAMQP channel adapters and gateways for Spring Integration. Provides RabbitMQ message-driven and polling inb...34.4 Spring Integration Kafka AdapterKafka channel adapters for Spring Integration. Provides message-driven inbound adapters, outbound channel a...34.4 Termii Messaging APISend single, bulk, and number-based messages.34.0 PubNub REST APISingle REST surface for publish, subscribe (long-poll), presence, history, signal, and App Context. Pub/Sub...33.9 GroupMe API v3REST + JSON API for GroupMe groups, memberships, messages, chats, likes, blocks, users, and bots, plus a Ba...33.8 Scroll Native BridgeCanonical L1 L2 bridge for ETH, ERC-20, and arbitrary messages between Ethereum mainnet and Scroll. Backed...33.8 Apache EventMesh Messaging APIEvent-driven messaging via TCP, HTTP, and gRPC protocols. Events follow the CloudEvents specification. Supp...33.7 Modal Dicts and QueuesDistributed key-value store (modal.Dict) and distributed queue (modal.Queue) for passing state and messages...33.7 Modal Queues APIDistributed FIFO queues for asynchronous workloads, work-stealing, and producer/consumer patterns across fu...33.7 Zulip REST APIThe Zulip REST API powers the Zulip web and mobile apps. It provides programmatic access to messages, strea...33.6 KakaoTalk Message APIKakaoTalk Message sends template-based messages from a Kakao-Linked app to the authenticated user themselve...33.2 KakaoTalk Sharing APIKakaoTalk Sharing lets external apps and websites share rich "Feed", "List", "Location", "Calendar", "Comme...33.2 RabbitMQ AMQP Messaging APIAMQP 0-9-1 messaging protocol for producing and consuming messages via exchanges, queues, and bindings with...33.2 Towns ProtocolTowns Protocol is an open, decentralized messaging protocol built on Base. Builders integrate via first-par...32.8 Pushbullet HTTP APIREST API for sending and managing pushes, devices, chats, channels, subscriptions, and file uploads across ...32.4 Apache Pulsar Messaging APIPulsar messaging protocol for producing and consuming messages on topics, with support for multiple subscri...32.2 LiveChat Agent Chat APIREST and RTM APIs for agents to manage chats, send messages, transfer conversations, and update statuses. A...32.2 LiveChat Customer Chat APIREST and RTM APIs for customers to start and participate in chats with agents on LiveChat-powered websites....32.2 WATI WhatsApp Business APITenant-scoped REST API for sending WhatsApp template and session messages, managing contacts, assigning ope...31.7 Garmin inReach Portal ConnectEnterprise API for organizations to integrate inReach satellite communicator data — two-way messaging, loca...31.6 Aircall Messaging APISend and receive SMS/MMS and group messages.31.2 Hologram Messaging APIThe Messaging API from Hologram — 1 operation(s) for messaging.30.9 Apache Kafka Admin APIApache Kafka's Admin REST API enables creating and managing topics, partitions, consumer groups, and cluste...30.8 Messaging APIsA portfolio of messaging APIs including SMS Middle East and Africa, Messaging Pro Cameroon, Voice as a Serv...30.8 NATS Management APINATS is a lightweight, high-performance messaging system for distributed applications. Its management API p...30.8 Strimzi Operator APIThe Strimzi Operator API is expressed through Kubernetes Custom Resource Definitions (CRDs). Operators are ...30.8 Spring Cloud Stream Core APICore programmatic API for building message-driven microservice applications. Provides functional programmin...30.7 Spring Cloud Stream Kafka BinderApache Kafka binder for Spring Cloud Stream providing Kafka producer and consumer binding configuration, Ka...30.7 Spring Cloud Stream RabbitMQ BinderRabbitMQ binder for Spring Cloud Stream providing AMQP-based messaging with support for exchanges, queues, ...30.7 Agora Chat APIThe Agora Chat API provides scalable in-app messaging with one-to-one chat, group chat, chat rooms, threads...30.6 Agora Signaling API (RTM)The Agora Signaling API (formerly Real-Time Messaging / RTM) provides real-time low-latency synchronization...30.6 Crisp Realtime (Webhooks + RTM) v1Crisp realtime surface combining HTTP Web Hooks (signed plugin hooks and unsigned website hooks) and the So...30.6 Vetspire Conversations & Communications APIGraphQL operations over the Conversations and Marketing domains - client messaging threads (SMS/email), tem...30.3 Matrix Client-Server APIREST API used by Matrix clients to communicate with a homeserver, covering login, room creation and managem...29.8 Kafka Consumer APIAPI for subscribing to topics and processing streams of records.29.3 Kafka Producer APIAPI for publishing streams of records to Kafka topics.29.3 AMQP Messaging APIAsyncAPI specification for AMQP messaging patterns including publish/subscribe, request/reply, and point-to...29.1 Spring Batch 5.1 Integration APISpring Batch integration with Spring Integration for remote partitioning, remote chunking, and message-driv...28.9 Deutsche Telekom Rich Communication Services APIImprove customer experience using Rich Communication Services for branded, interactive messaging that exten...28.6 Deutsche Telekom SMS APIProgrammatically send and receive text messages in practically every country through Deutsche Telekom's CPa...28.6 Mainstay APIAdmitHub/Mainstay REST API v1.0 for syncing student and employee records and engagement data between Mainst...28.5 Apache ServiceMix Messaging APIThe Messaging API from Apache ServiceMix — 1 operation(s) for messaging.28.2 AMQPAdvanced Message Queuing Protocol. AMQP 1.0 is both an OASIS standard and an International Standard (ISO/IE...27.3 IBM MQEnterprise messaging middleware from IBM. Long the de facto standard for assured-once message delivery in r...27.3 NATSCNCF incubating high-performance, lightweight messaging system designed for cloud, edge, and IoT. Supports ...27.3 STOMPSimple (or Streaming) Text Oriented Messaging Protocol. Lightweight, text-based wire protocol for message-o...27.3 Twilio API (reference provider)Reference provider with strong agent-readiness signals on the messaging side — published OpenAPI, idempoten...26.6 MirrorFly Chat Platform APIToken-authenticated REST API for building in-app chat, split into User APIs and Admin APIs (users, contacts...26.2

Emerging 34 Early or largely undocumented

Nitric Queue ResourceSDK resource for declaring durable message queues for batch and deferred processing. Nitric maps it to a cl...26.0 ChatwikChatwik's publicly consumable surfaces: an llms.txt / llms-full.txt agent-native discovery file and product...25.0 Urbit HTTP API (Tlon)The Urbit ship HTTP API (Eyre channels) that powers Tlon Messenger. Clients authenticate to a ship with its...25.0 Skype URIs APISkype URIs provide a mechanism for launching Skype actions from web pages and applications. Developers can ...24.8 NATS JetStreamPersistence layer for the NATS messaging system providing at-least-once and exactly-once streaming, key/val...24.4 Qualia APIThe Qualia API is a read-write GraphQL API over the Qualia title, escrow and closing platform. It lets part...24.3 tyntec Conversations APIOne API for WhatsApp Business, Viber, and SMS. Send single (POST /messages) or bulk (POST /bulks) messages,...23.8 tyntec SMS APISend and receive text messages over tyntec's global A2P SMS network. Send via POST /messaging/v1/sms, retri...23.8 Bloomberg IB (Instant Bloomberg)Secure messaging platform built into the Bloomberg Terminal enabling real-time communication between financ...23.5 AsyncAPI SpecificationAsyncAPI is the open standard for describing event-driven and message-driven APIs across protocols such as ...22.5 Wand AI Workforce APIThe platform API behind Wand's Process Agentizer product, named "AI Workforce API" in Wand's own machine-re...21.2 myBots Tenant APIThe bearer-gated REST API the Mia AI application calls to operate a tenant's agents, subscription and chann...20.6 MassTransit Messaging FrameworkMassTransit provides a consistent abstraction on top of message transports like RabbitMQ, Azure Service Bus...20.5 Descartes B2B API ConnectivityReal-time B2B connectivity over the Descartes Global Logistics Network, complementing traditional EDI. Prov...20.1 Gupshup Messaging APISend WhatsApp session messages.20.1 Gupshup SMS APIBroadcast SMS to a single number or many numbers programmatically via POST /msg on the /sm surface. Note - ...20.1 MQTT ProtocolMQTT (Message Queuing Telemetry Transport, ISO/IEC 20922) is a lightweight pub/sub messaging protocol widel...19.9 LivePerson Conversational Cloud APIComprehensive set of REST APIs for managing conversations across messaging channels, including agent operat...19.8 LivePerson Messaging Operations APIReal-time and historical operational metrics for messaging conversations, including queues, agent activity,...19.8 Singtel CPaaS SMS APIApplication-to-person SMS sending and receiving for business applications, sold as part of the Singtel CPaa...19.8 Lazada Chat (IM) APIBidirectional buyer-seller messaging API for in-app conversations on Lazada — including sending and retriev...19.7 Hostfully REST APIHostfully Property Management Platform REST API v3.x covering properties (single and multi-unit), leads (in...19.4 TranZak SMS APIREST API for sending marketing bulk SMS messages and OTP/verification codes. Supports up to 500 recipients ...19.4 Lufthansa Cargo CargoIMP APIPrior-agreement API product listed as CargoIMP in the portfolio, referencing the legacy IATA Cargo Intercha...19.0 Lufthansa Cargo CargoXML APIPrior-agreement API product named CargoXML in the Lufthansa Cargo portfolio, referencing the IATA Cargo-XML...19.0 Xcel Energy Messaging APIText and HTML messages targeted at end-users.18.2 Moxtra REST APIMoxtra's REST API for building embedded collaboration experiences, covering users, binders (workspaces), pa...17.8 Naver Cloud SENS Messaging APISENS (Simple & Easy Notification Service) sends SMS, LMS, MMS, Alimtalk (KakaoTalk channel), Friend Talk, a...17.7 POSIX Message Queues APIPOSIX message queue interfaces for exchanging messages between processes with priority support.17.5 Subsplash Groups and Messaging APIManage groups, group membership, and messaging, and trigger push notifications and in-app messages through ...17.2 JD Open Platform Customer Service APICustomer service (客服) APIs integrate with JD's IM and service workflows — letting merchants pull customer i...16.6 SMS Messaging HubA2P SMS messaging gateway for sending one-time-passcodes, alerts, and marketing messages to Vodafone subscr...13.8 Inmarsat IsatData Pro Messaging APIThe IsatData Pro (IDP) Messaging API is a web service for sending and receiving short binary messages over ...13.5 Jakarta MessagingThe Jakarta Messaging (formerly Java Message Service) specification for enterprise messaging and asynchrono...12.4

Minimal 4 Almost no public developer surface

Rakuten CPaaS SMS / Messaging APICarrier-grade SMS API for sending and receiving A2P and P2A SMS at scale on the Rakuten Mobile network, wit...9.8 Sectra HL7 Integration InterfaceHL7 v2 messaging interface for exchanging orders, scheduling, worklist, and results/reports between Sectra ...8.5 ISAAC Messaging APIModeled interface for driver-to-dispatch messaging and in-cab workflow forms exchanged through the ISAAC pl...8.4 WhatsApp Data APIRapidAPI-hosted REST API for WhatsApp number verification, profile display name, and profile picture lookup...7.8

Unrated 1 Not yet scored

App.net Stream APIThe App.net Stream API — a RESTful, OAuth 2.0-secured social API covering posts, users, follows, channels/m...

Companies reaching this through an API (112)

These companies publish an API, specification or operation carrying “Messaging” but do not classify their business under it. Listed unranked and kept out of the count above, because one tagged operation is not a statement about what a company does.

ABC Trainerize Ada Agent Readiness Agora Aircall Amazon Q API Specifications Appgain Apple Application Research Appwrite Artera Azure Event Hubs Backendless Bloomberg Terminal Botpress Casey's General Stores China Mobile Cisco CleanCloud CleverTap Cloudflare CloudGuard Descartes Systems Group Deutsche Telekom Dify Dotdigital Elation Health FedNow Service Friedrich-Alexander-Universität Erlangen-Nürnberg Garmin Genesys Google Google Workspace GP Connect HERE Hologram Hostaway Hostfully HubSpot IBM Inmarsat Instagram ISAAC Instruments JD.com (Jingdong) Jupyter Notebook Kno2 KrakenD Lazada Lichess

Show all 112 companies ↓

Lodgify Lufthansa Cargo ManyChat McAfee (Trellix) Microsoft Azure Microsoft Teams Modal MoMo MuleSoft Nash NATS Naver NHS Digital Nitric Oracle Oracle Database Orange Business Phone Com Photon Engine Qualia Red Hat Refinitiv Eikon Roblox Engine API Rokid Salesforce Salesforce Marketing Cloud Salesforce Service Cloud APIs SAP SAP Integration Suite Sarj AI Developer API SCADA Scalable Software and Systems Scroll Sectra ServiceNow Shanghai Jiao Tong University Smoobu Spring Batch 5.1 Spring WebFlux StackOne Streaming Submittable Subsplash Technical University of Berlin Telesign Telnyx TranZak Trellix Twitch Unified.to UNIX System Call Vault12 Veterans Affairs Vetspire Wand WhatsApp Workday Integration Wunderkind Xcel Energy Zendesk Zoho Zoom

Score breakdown

Frequency

76.3

log-scaled weighted occurrences

Breadth

9.3

spread across providers

Quality lift

42.6

mean composite of providers using it

Cohesion

23.4

strength of nearest seed neighbor

Where this tag comes from

Provider tag338

Api tag257

Openapi tag34

Openapi op tag113

Cohort brief

Auto-generated

The 311 providers in the APIs.io catalog tagged Messaging, scored on the Kin Score. Every figure below is computed from the catalog — nothing here is written.

Providers

311

all scored

Mean Kin Score

38.7

+14.8 vs catalog 23.9

Mean Agent Readiness

22.5

+10.5 vs catalog 12

Spread

1.5–89.3

median 38.1 · σ 19

How the 311 split by band

Exemplar 23Strong 46Developing 79Thin 85Emerging 47Minimal 31

Facet averages, against the whole catalog

Facet	This cohort	Catalog	Difference	Scored
Contract Quality	40.3	19.8	+20.5	311
Developer Ergonomics	40.1	23.4	+16.7	311
Operational Transparency	27.1	13.9	+13.2	311
Access Clarity	39.5	26.5	+13	311
Discoverability	68.1	61.2	+6.9	311
Contract Governance	10.4	6.4	+4	311

A facet is averaged over the members that carry it, not over the whole cohort — the “Scored” column is that count. Averaging an absent facet as zero would score our own coverage gaps as the providers’ posture.

What this cohort publishes

Artifact	This cohort	Catalog	Difference
MCP server (any)	19%	10%	+9
MCP server (first-party)	21%	13%	+8
Agent Skills	0%	0%	0
OAuth scopes	22%	11%	+11
Security	97%	96%	+1
Arazzo workflows	5%	2%	+3
Governance rules	28%	14%	+14

mcp_pct counts any mcp/ artifact including ones API Evangelist derived from the provider OpenAPI; mcp_first_party_pct counts only servers the provider publishes. Prefer the latter.

Top by Kin Score

1 Customer.io 89.3
2 Brevo 87.3
3 Amazon Pinpoint 82.2
4 Braze 80.4
5 Svix 80.4
6 Boom Ai 79.9
7 Confluent 79
8 Nylas 76.6
9 Amazon SES 76.3
10 Infobip 75.4

Work with this as data

Every tag here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for tags

7 MCP tools reach this

find_tagsBrowse and filter every tag in the catalog.
get_cohortThis tag as a scored cohort — every provider carrying it, with scores.
cohort_statsPRO — the distribution across this tag: mean, median, band split, adoption rates.
cohort_rankingsPRO — the leaderboard, on composite AND agent-readiness axes.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This tag

curl "https://apis.io/api/v1/tags/messaging"

All tags

curl "https://apis.io/api/v1/tags?limit=25"

As a scored cohort

curl "https://apis.io/api/v1/cohorts/tag/messaging"

The distribution (Pro)

curl "https://apis.io/api/v1/cohorts/tag/messaging/stats" \
  -H "X-API-Key: $APIS_IO_KEY"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.

Messaging

Providers using this tag (337)

APIs with this tag (256)