Feature
Server-Sent Events & Streaming Responses
Incrementally streamed HTTP responses.
124 providers
1153 APIs
119 declared variants
Responses stream token-by-token or event-by-event over a long-lived HTTP connection. The default delivery mode for LLM completions and progressive result sets.
124 API providers on the APIs.io network offer server-sent events & streaming responses. The highest-rated are SendGrid, Anthropic, Amazon S3, Fastly, Ashby.
Providers
Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.
Exemplar 6 Complete, well-documented, and agent-ready
SendGrid
SendGrid is a cloud-based email delivery platform that provides reliable transactional and marketing email ...
Anthropic
Anthropic is an AI safety company and creator of the Claude family of large language models (Opus, Sonnet, ...
Amazon S3
Amazon Simple Storage Service (S3) is an object storage service offering industry-leading scalability, data...
Fastly
Fastly is an edge cloud platform that helps customers create great digital experiences quickly, securely, a...
Ashby
Ashby is a modern all-in-one recruiting platform combining Applicant Tracking System (ATS), sourcing/CRM, i...
Polygon
Polygon (Polygon.io, rebranded as Massive in early 2026) provides real-time and historical market data APIs...
Strong 30 Solid coverage with minor gaps
NVIDIA NIM
NVIDIA NIM (NVIDIA Inference Microservices) is a catalog of GPU-accelerated, containerized AI inference mic...
Vapi
Vapi is a San Francisco-based voice AI platform that lets developers build real-time, low-latency voice age...
Meta
Collection of Meta (Facebook) platform APIs for social networking, messaging, advertising, content publishi...
Raygun
Raygun is an application monitoring platform that combines Crash Reporting, Real User Monitoring (RUM), and...
Amazon EFS
Amazon Elastic File System (EFS) provides a simple, serverless, set-and-forget elastic file system for use ...
Claude
Anthropic's Claude AI assistant API for natural language processing and conversation.
Youtube
YouTube APIs provide programmatic access to YouTube data including videos, playlists, channels, user intera...
Auth0
Auth0 (now part of Okta) is a leading identity-as-a-service platform providing authentication and authoriza...
Mailchimp
Mailchimp is an Intuit company providing a marketing automation platform and email marketing service for ma...
Moniepoint
Moniepoint is Africa's all-in-one financial platform for small and medium-sized businesses and individuals ...
Adobe
Adobe provides APIs and developer resources for its creative, document, and experience cloud platforms. Dev...
Soracom
Soracom is a global IoT cellular connectivity and platform provider headquartered in Tokyo, founded in 2014...
Amazon Location Service
Amazon Location Service provides location-based services including maps, places, routes, trackers, and geof...
Blockfrost
Blockfrost is a RESTful API service providing access to the Cardano blockchain and its ecosystem. It serves...
Amazon Data Exchange
AWS Data Exchange makes it easy to find, subscribe to, and use third-party data in the cloud. Qualified dat...
Amazon IoT SiteWise
AWS IoT SiteWise is a managed service that makes it easy to collect, store, organize, and monitor industria...
fireblocks
Fireblocks is an institutional digital-asset and stablecoin infrastructure company providing MPC-secured cu...
Factset
FactSet creates flexible, open data and software solutions for tens of thousands of investment professional...
Adobe Creative Cloud
Adobe Creative Cloud is a suite of software and cloud services for graphic design, video editing, web devel...
Pluralsight
APIs for the Pluralsight technology skills and engineering intelligence platform, providing access to cours...
Amazon MediaConnect
AWS Elemental MediaConnect is a high-quality transport service for live video that provides the reliability...
Amazon MediaTailor
AWS Elemental MediaTailor is a channel assembly and personalized ad-insertion service that enables you to m...
Greenhouse
Greenhouse Software is an enterprise applicant tracking system (ATS) and end-to-end hiring platform spannin...
Adobe Creative Suite
Adobe Creative Suite is a collection of professional software applications for graphic design, video editin...
Amazon DMS
AWS Database Migration Service (AWS DMS) helps you migrate databases to AWS quickly and securely. The sourc...
DroneDeploy
DroneDeploy is the unified reality-capture platform for construction, agriculture, mining, energy, oil & ga...
Toolhouse
Toolhouse is a Backend-as-a-Service platform for building, deploying, and managing "AI workers" (Toolhouse'...
Ariba Guided Buying
SAP Ariba Guided Buying provides a consumer-like shopping experience for enterprise procurement, enabling e...
OpenRouter
OpenRouter is an API platform that provides unified access to multiple AI language models through a single ...
Recraft
Recraft is a London-based AI design platform — founded in 2023 by Anna Veronika Dorogush (creator of the Ca...
Developing 46 Usable, with meaningful gaps to close
Algorand
Algorand is a pure proof-of-stake blockchain platform designed for speed, security, and decentralization. I...
Barndoor
Barndoor AI is the control plane for agentic AI, providing secure access and governance for AI agents and M...
Salesforce Automation
A collection of Salesforce APIs for automating business processes, sales operations, and customer relations...
Google Quantum AI
Google Quantum AI is Google's quantum-computing research and engineering arm, building superconducting quan...
Livepeer
Livepeer is the open, permissionless protocol for video transcoding, streaming, and AI video inference, coo...
Runway
Runway is an applied AI research company that builds generative AI tools for creative professionals. Their ...
VesselFinder
VesselFinder is a maritime intelligence company operating a global AIS vessel-tracking network (terrestrial...
Bridge
Bridge (Bridge Interactive / Bridge Data Output) is a Zillow Group company that runs the Bridge Platform — ...
Censys
Censys is an internet intelligence and attack surface management platform that continuously scans the publi...
Giphy
GIPHY is the world's largest library of GIFs, stickers, animated emoji, and Clips (GIFs with sound), with a...
Split
Split, now part of Harness Feature Management and Experimentation, is a feature flag and experimentation pl...
Triton One
Triton One is a high-performance Solana RPC and blockchain infrastructure provider operating globally distr...
Rollbar
Rollbar is a real-time error tracking and monitoring platform for software teams. It automatically captures...
Perforce
Perforce Software provides enterprise-scale development tools, including version control, application lifec...
OpsGenie
OpsGenie is an incident management and alerting platform, now part of Atlassian, that helps operations team...
Pipedrive
Pipedrive is a sales CRM and pipeline management tool focused on small and mid-market teams. The Pipedrive ...
Vonage
Vonage (part of Ericsson) provides cloud communications APIs for voice, SMS, messaging, video, and verifica...
Amazon Global Accelerator
Amazon Global Accelerator is a networking service that improves the performance and availability of applica...
Leonardo.AI
Leonardo.AI is an Australian generative-AI company (acquired by Canva in July 2024) offering a Production A...
Gainsight
Gainsight is a customer success platform that helps companies retain and grow their customer base through d...
Canva
APIs for the Canva design platform, enabling developers to integrate Canva's design tools and functionality...
Argo CD
Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes that automates the deployment of a...
Heroku
Heroku is a cloud platform as a service (PaaS) that enables developers to build, run, and operate applicati...
Smithery
Smithery is an MCP server registry and hosting platform that lets developers discover, publish, and connect...
Blockdaemon
Blockdaemon is an institutional blockchain infrastructure company founded in 2017 by Konstantin Richter. It...
Apache JMeter
Apache JMeter is an open-source Java application designed for load testing functional behavior and measurin...
Verisk
Verisk (formerly ISO) is a leading data analytics and technology company serving the insurance, energy, and...
Plaid
Plaid is a financial technology company that provides an API platform for businesses to connect with user's...
Tensor
Tensor is the Solana-native NFT marketplace and trading protocol founded by Tensor HQ and now stewarded by ...
Google Apps Script
The Apps Script API provides programmatic access to manage Google Apps Script projects, deployments, and ex...
EVE Online
EVE Online is a massively multiplayer online (MMO) space game published by CCP Games. The EVE Online third-...
Forethought
Forethought is a San Francisco-based generative AI customer-support platform. Its multi-agent product suite...
Close
Close is an inside-sales CRM with calling, email, SMS, and WhatsApp built in. The Close API exposes leads, ...
AspenTech
AspenTech (Aspen Technology, Inc.) is a global leader in industrial software for asset optimization across ...
nOps
nOps is an AI-powered cloud cost visibility and optimization platform that helps organizations reduce their...
Apache POI
Apache POI is a Java API for manipulating various file formats based upon the Office Open XML standards (OO...
Ariba
SAP Ariba provides cloud-based procurement and supply chain collaboration solutions. These APIs enable inte...
Blender
Blender is the free and open source 3D creation suite supporting the entirety of the 3D pipeline including ...
Test Plans
Structured documentation outlining test objectives, scope, approach, resources, schedule, and deliverables ...
Amazon Nova
Amazon Nova is a new generation of state-of-the-art foundation models from Amazon that deliver a compelling...
Google
Google's public APIs and services.
Mubert
Mubert is a generative AI music platform that composes royalty-free, DMCA-free music in real time from mill...
Adobe Suite
Collection of Adobe Creative Cloud and Experience Cloud APIs.
Gemini
Google's Gemini API provides access to state-of-the-art generative AI models for text generation, multimoda...
MarineTraffic
MarineTraffic is the leading maritime intelligence and AIS ship-tracking platform — now part of Kpler. The ...
Tradeweb
Tradeweb Markets is a leading global operator of electronic marketplaces for rates, credit, equities, and m...
Thin 26 Limited public surface area
US Census Bureau
The U.S. Census Bureau is the federal statistical agency responsible for producing data about the American ...
Docling
Docling is an open-source toolkit for parsing diverse document formats — PDF, DOCX, PPTX, XLSX, HTML, image...
IMDb-API
Community web service (operated under the IMDb-API / TV-API brand) providing movie, TV series and cast info...
Unity
Unity is a real-time 3D content creation platform — the Unity engine powers cross-platform games, simulatio...
Alliance for OpenUSD
The Alliance for OpenUSD (AOUSD) is a Linux Foundation project dedicated to promoting interoperability of 3...
Intercom
Intercom is an AI-powered customer service platform that enables businesses to build seamless customized ex...
Langflow
Langflow is an open-source low-code visual builder for AI agents, RAG pipelines, and LangChain-based workfl...
NOAA — National Oceanic and Atmospheric Administration
The National Oceanic and Atmospheric Administration (NOAA) is the United States scientific and regulatory a...
NASA Open APIs
NASA Open APIs is the National Aeronautics and Space Administration's unified, public developer portal expo...
CAT
CAT is the brand name and ticker symbol for Caterpillar Inc. (NYSE: CAT), the world's leading manufacturer ...
Baker Hughes
Baker Hughes is an energy technology company providing solutions to energy and industrial customers worldwi...
Audatex
Audatex (part of Solera Holdings) provides automotive claims and repair solutions with data and technology ...
Assertible
Assertible provides a reliable first line of defense against web service failures by providing simple and p...
Loadsmart
Loadsmart is a digital freight technology company and 4PL that connects shippers, carriers, warehouses, and...
Chainguard
Chainguard builds, secures, and maintains a catalog of hardened, minimal container images and software supp...
Three.js
Three.js is an open-source JavaScript 3D library originally created by Ricardo Cabello (mrdoob) in 2010 and...
Amazon Audit Manager
AWS Audit Manager helps you continuously audit your AWS usage to simplify how you assess risk and complianc...
Riskified
Riskified (NYSE RSKD) is an Israeli ecommerce risk-management platform that uses machine learning and a glo...
Lex Machina
Lex Machina is a legal analytics platform owned by LexisNexis that transforms raw court documents and docke...
Krea
Krea is a real-time AI creative suite that lets designers, filmmakers, brand teams, and everyday creators g...
Volvo Cars
Volvo Cars is a Swedish premium automotive OEM (headquartered in Gothenburg, owned by Geely) that operates ...
Imgix
imgix is a real-time image processing and CDN service that helps developers optimize images, improve page s...
Capella Space
Capella Space operates a constellation of synthetic aperture radar (SAR) satellites and provides on-demand,...
Syndica
Syndica is a Solana-only infrastructure company building developer infrastructure for Web3. Its production ...
Apache Tapestry
Apache Tapestry is a component-oriented framework for creating highly scalable web applications in Java. It...
Axonius
Axonius is a cybersecurity asset management platform providing SaaS management, device discovery, and secur...
Emerging 15 Early or largely undocumented
Certero
Certero is an enterprise IT Asset Management (ITAM) software vendor whose flagship CerteroX platform unifie...
Bloomberg Indices
Bloomberg Indices are a comprehensive family of fixed income, equity, commodity, and multi-asset benchmark ...
Bloomberg Query Language (BQL)
Bloomberg Query Language (BQL) is a proprietary query language for accessing, filtering, aggregating, and c...
AstroPay
AstroPay is a Uruguay-founded fintech and electronic money institution offering a multicurrency wallet, vir...
Greenly
Greenly is a Paris-headquartered (with offices in London and New York) carbon accounting platform focused o...
Wireshark
Wireshark is the world's foremost and widely-used free and open-source network protocol analyzer. It lets y...
Benchmark Minerals
Benchmark Mineral Intelligence is the world's leading market intelligence and price reporting agency for th...
HPE Aruba Networking
HPE Aruba Networking is the networking business unit of Hewlett Packard Enterprise (NYSE HPE), born of Arub...
Ecologi
Ecologi is a Bristol, UK climate action platform and B Corp founded in 2019 that lets individuals and busin...
Scenario
Scenario is a Paris- and San Francisco-headquartered AI platform for game asset generation founded in 2021 ...
Affiliated Managers Group
Affiliated Managers Group (AMG) is a global asset management company that partners with outstanding indepen...
CCPA (California Consumer Privacy Act)
The California Consumer Privacy Act (CCPA), amended by the California Privacy Rights Act (CPRA), is a state...
Sardine
Sardine is a San Francisco-based fraud prevention, AML compliance, and risk management platform for fintech...
Babylon.js
Babylon.js is an Apache-2.0 licensed, TypeScript-first open-source 3D engine and rendering framework sponso...
CMA CGM
CMA CGM is a Marseille-headquartered French container shipping, logistics, and port operator and the third-...
Minimal 1 Almost no public developer surface
What Providers Actually Declared
This feature is a canonical term. These are the free-text strings
providers wrote in their own apis.yml that map onto it.
$0.05/min Vapi orchestration fee on Build plan; model and voice costs passed at cost$110B+ digital assets secured; $10B+ staked on Blockdaemon validators; 250K+ nodes launched; 80+ protocols200+ integration partners across HRIS, assessments (SHL, CodeSignal, HackerRank, CoderPad), background checks (HireRight, Checkr), video (Zoom), comms (Slack, Google Workspace, Microsoft 365), and contract / offer letter tools (Pave, Ironclad, Metaview)3D assets and a Volvo simulator surface for digital and immersive product experiences.3D model generation via Rodin V2 and 3D model asset management3rd-largest container carrier worldwide; fleet of 593 vessels and 4.5M TEU capacity6,000+ expert witnesses trackedAIS vessel positions (live + delayed)API Test AssertionsAddressables and Cloud Content Delivery for live asset updates without app re-submissionAfrica's largest merchant acquirer — ~10M business and individual accounts, $17B monthly TPV, 26M daily payments processedApproval ProcessesAssertionsAssessment delegation to process owners and resource ownersAsset DiscoveryAsset LibraryAsset Library SystemAsset ManagementAsset Management IntegrationAsset Manager DAM and Asset CleanupAsset ModelingAsset Performance ManagementAsset PipelineAsset ResolutionAsset TelematicsAsset TrackingAsset editingAsset storage (5 GB Free, 100/500 GB paid)Carbon Project Assessment Framework (CPAF) and Nature Project Assessment Framework (NPAF)Cards-as-a-Service issuing for businesses (virtual and physical, branded)ChainStream real-time streaming API — transactionsSubscribe, slotsSubscribe, blocksSubscribe over WebSocket JSON-RPC 2.0 at wss://chainstream.api.syndica.ioChannel AssemblyClaims Assessment APIClaude Managed Agents (beta) — Agents, Sessions, Environments with SSE streaming and managed sandboxesContent management and digital asset managementContext Variables — typed values (string, number, boolean, list, object) passed into Solve conversationsCross-Asset Data AccessCustom AssemblyDeployment Tracking — release markers correlated with new/regressed error groupsDigital Asset Management
Showing 40 of 119 declared variants