Feature
Server-Sent Events & Streaming Responses
Incrementally streamed HTTP responses.
124 providers
834 APIs
118 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 Messagebird, Mailchimp, SendGrid, Close, Adobe.
Providers
Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.
Exemplar 15 Complete, well-documented, and agent-ready
MessagebirdMessageBird, which trades as Bird, is a Dutch cloud communications company whose platform carries email, SM...MailchimpMailchimp is an Intuit company providing a marketing automation platform and email marketing service for ma...SendGridSendGrid is a cloud-based email delivery platform, acquired by Twilio in 2019, that provides transactional ...CloseClose is an inside-sales CRM with calling, email, SMS, and WhatsApp built in. The Close API exposes leads, ...AdobeAdobe provides APIs and developer resources for its creative, document, and experience cloud platforms. Dev...AnthropicAnthropic is an AI safety company and the creator of the Claude family of large language models (Opus, Sonn...Adobe SuiteAdobe operates one of the largest first-party API estates in software: 70 published OpenAPI and Swagger con...PluralsightAPIs for the Pluralsight technology skills and engineering intelligence platform, providing access to cours...PlaidPlaid is a US financial-technology company and data-network aggregator that provides an API platform for bu...Amazon S3Amazon Simple Storage Service (S3) is an object storage service offering industry-leading scalability, data...NVIDIA NIMNVIDIA NIM (NVIDIA Inference Microservices) is a catalog of GPU-accelerated, containerized AI inference mic...Auth0Auth0 (now part of Okta) is a leading identity-as-a-service platform providing authentication and authoriza...FactsetFactSet creates flexible, open data and software solutions for tens of thousands of investment professional...CanvaCanva is the visual design platform used by hundreds of millions of people, and it exposes four distinct de...Massive (formerly Polygon.io)Polygon (Polygon.io, rebranded as Massive in early 2026) provides real-time and historical market data APIs...
Strong 26 Solid coverage with minor gaps
CumulocityCumulocity is an enterprise AIoT (Artificial Intelligence of Things) platform that connects, manages, and a...FastlyFastly is an edge cloud platform that helps customers create great digital experiences quickly, securely, a...CensysCensys is an internet intelligence and attack surface management platform that continuously scans the publi...BarndoorBarndoor AI is the control plane for agentic AI, providing secure access and governance for AI agents and M...FireblocksFireblocks is an institutional digital-asset and stablecoin infrastructure company providing MPC-secured cu...RaygunRaygun is an application monitoring platform that combines Crash Reporting, Real User Monitoring (RUM), and...Amazon NovaAmazon Nova is a new generation of state-of-the-art foundation models from Amazon that deliver a compelling...GiphyGIPHY is the world's largest library of GIFs, stickers, animated emoji, and Clips (GIFs with sound), with a...Amazon Location ServiceAmazon Location Service provides location-based services including maps, places, routes, trackers, and geof...PerplexityPerplexity AI is an answer engine that delivers accurate answers to complex questions using large language ...Leonardo.AILeonardo.AI is an Australian generative-AI company (acquired by Canva in July 2024) offering a Production A...SoracomSoracom is a global IoT cellular connectivity and platform provider headquartered in Tokyo, founded in 2014...Amazon EFSAmazon Elastic File System (EFS) provides a simple, serverless, set-and-forget elastic file system for use ...Google Quantum AIGoogle Quantum AI is Google's quantum-computing research and engineering arm, building superconducting quan...Amazon Global AcceleratorAmazon Global Accelerator is a networking service that improves the performance and availability of applica...BridgeBridge (Bridge Interactive / Bridge Data Output) is a Zillow Group company that runs the Bridge Platform — ...MoniepointMoniepoint is Africa's all-in-one financial platform for small and medium-sized businesses and individuals ...MetaCollection of Meta (Facebook) platform APIs for social networking, messaging, advertising, content publishi...US Census BureauThe U.S. Census Bureau is the federal statistical agency responsible for producing data about the American ...YoutubeYouTube APIs provide programmatic access to YouTube data including videos, playlists, channels, user intera...Salesforce AutomationA collection of Salesforce APIs for automating business processes, sales operations, and customer relations...Amazon MediaConnectAWS Elemental MediaConnect is a high-quality transport service for live video that provides the reliability...GoogleGoogle's public APIs and services.Amazon IoT SiteWiseAWS IoT SiteWise is a managed service that makes it easy to collect, store, organize, and monitor industria...Benchmark MineralsBenchmark Mineral Intelligence is the world's leading market intelligence and price reporting agency for th...PipedrivePipedrive is a sales CRM and pipeline management tool focused on small and mid-market teams. The Pipedrive ...
Developing 39 Usable, with meaningful gaps to close
Amazon Data ExchangeAWS Data Exchange makes it easy to find, subscribe to, and use third-party data in the cloud. Qualified dat...GreenhouseGreenhouse Software is an enterprise applicant tracking system (ATS) and end-to-end hiring platform spannin...Amazon MediaTailorAWS Elemental MediaTailor is a channel assembly and personalized ad-insertion service that enables you to m...ClaudeAnthropic's Claude AI assistant API for natural language processing and conversation.IntercomIntercom is an AI-powered customer service platform that enables businesses to build seamless customized ex...Adobe Creative CloudAdobe Creative Cloud is a suite of software and cloud services for graphic design, video editing, web devel...GeminiGoogle's Gemini API provides access to state-of-the-art generative AI models for text generation, multimoda...LivepeerLivepeer is a decentralized video infrastructure network. Independent orchestrators run GPU hardware to pro...AudatexAudatex (a Solera company) provides automotive claims and repair solutions with data and technology service...RunwayRunway is an applied AI research company that builds generative AI tools for creative professionals. Their ...ToolhouseToolhouse is a Backend-as-a-Service platform for building, deploying, and managing "AI workers" (Toolhouse'...TensorTensor is the Solana-native NFT marketplace and trading protocol founded by Tensor HQ and now stewarded by ...VonageVonage (part of Ericsson) provides cloud communications APIs for voice, SMS, messaging, video, and verifica...Adobe Creative SuiteAdobe Creative Suite is a collection of professional software applications for graphic design, video editin...VesselFinderVesselFinder is a maritime intelligence company operating a global AIS vessel-tracking network (terrestrial...AxoniusAxonius is a cybersecurity asset management platform (Axonius Asset Cloud) that aggregates device, user, cl...Amazon DMSAWS Database Migration Service (AWS DMS) helps you migrate databases to AWS quickly and securely. The sourc...AlgorandAlgorand is a pure proof-of-stake blockchain platform designed for speed, security, and decentralization. I...AssertibleAssertible provides a reliable first line of defense against web service failures by providing simple and p...PerforcePerforce Software provides enterprise-scale development tools, including version control, application lifec...IMDb-APICommunity web service (operated under the IMDb-API / TV-API brand) providing movie, TV series and cast info...OpenRouterOpenRouter is an API platform that provides unified access to multiple AI language models through a single ...OpsGenieOpsGenie is an incident management and alerting platform, now part of Atlassian, that helps operations team...Triton OneTriton One is a high-performance Solana RPC and blockchain infrastructure provider operating globally distr...BlockfrostBlockfrost is a RESTful API service providing access to the Cardano blockchain and its ecosystem. It serves...BlockdaemonBlockdaemon is an institutional blockchain infrastructure company founded in 2017 by Konstantin Richter. It...HerokuHeroku is a cloud platform as a service (PaaS) that enables developers to build, run, and operate applicati...MarineTrafficMarineTraffic is the leading maritime intelligence and AIS ship-tracking platform — now part of Kpler. The ...ForethoughtForethought is a San Francisco-based generative AI customer-support platform. Its multi-agent product suite...NOAA — National Oceanic and Atmospheric AdministrationThe National Oceanic and Atmospheric Administration (NOAA) is the United States scientific and regulatory a...RollbarRollbar is a real-time error tracking and monitoring platform for software teams. It automatically captures...LoadsmartLoadsmart is a digital freight technology company and 4PL that connects shippers, carriers, warehouses, and...MubertMubert is a generative AI music platform that composes royalty-free, DMCA-free music in real time from mill...Apache JMeterApache JMeter is an open-source Java application designed for load testing functional behavior and measurin...LangflowLangflow is an open-source low-code visual builder for AI agents, RAG pipelines, and LangChain-based workfl...EVE OnlineEVE Online is a massively multiplayer online (MMO) space game published by CCP Games. The EVE Online third-...VeriskVerisk (formerly ISO) is a leading data analytics and technology company serving the insurance, energy, and...NASA Open APIsNASA Open APIs is the National Aeronautics and Space Administration's unified, public developer portal expo...Capella SpaceCapella Space operates a constellation of synthetic aperture radar (SAR) satellites and provides on-demand,...
Thin 21 Limited public surface area
KreaKrea is a real-time AI creative suite that lets designers, filmmakers, brand teams, and everyday creators g...SplitSplit, now part of Harness Feature Management and Experimentation, is a feature flag and experimentation pl...DoclingDocling is an open-source toolkit for parsing diverse document formats — PDF, DOCX, PPTX, XLSX, HTML, image...SyndicaSyndica is a Solana-only infrastructure company building developer infrastructure for Web3. Its production ...Google Apps ScriptThe Apps Script API provides programmatic access to manage Google Apps Script projects, deployments, and ex...CATCAT is the brand name and ticker symbol for Caterpillar Inc. (NYSE: CAT), the world's leading manufacturer ...RiskifiedRiskified (NYSE RSKD) is an Israeli ecommerce risk-management platform that uses machine learning and a glo...AspenTechAspenTech (Aspen Technology, Inc.) is a global leader in industrial software for asset optimization across ...GreenlyGreenly is a Paris-headquartered (with offices in London and New York) carbon accounting platform focused o...nOpsnOps is an AI-powered cloud cost visibility and optimization platform that helps organizations reduce their...Baker HughesBaker Hughes is an energy technology company providing solutions to energy and industrial customers worldwi...Lex MachinaLex Machina is a legal analytics platform owned by LexisNexis that transforms raw court documents and docke...Amazon Audit ManagerAWS Audit Manager helps you continuously audit your AWS usage to simplify how you assess risk and complianc...Imgiximgix is a real-time image processing and CDN service that helps developers optimize images, improve page s...Ariba Guided BuyingSAP Ariba Guided Buying provides a consumer-like shopping experience for enterprise procurement, enabling e...Alliance for OpenUSDThe Alliance for OpenUSD (AOUSD) is a Linux Foundation project dedicated to promoting interoperability of 3...Affiliated Managers GroupAffiliated Managers Group (AMG) is a global asset management company that partners with outstanding indepen...BlenderBlender is the free and open source 3D creation suite supporting the entirety of the 3D pipeline including ...Volvo CarsVolvo Cars is a Swedish premium automotive OEM (headquartered in Gothenburg, owned by Geely) that operates ...Apache POIApache POI is a Java API for manipulating various file formats based upon the Office Open XML standards (OO...Apache TapestryApache Tapestry is a component-oriented framework for creating highly scalable web applications in Java. It...
Emerging 18 Early or largely undocumented
ScenarioScenario is a Paris- and San Francisco-headquartered AI platform for game asset generation founded in 2021 ...Three.jsThree.js is an open-source JavaScript 3D library originally created by Ricardo Cabello (mrdoob) in 2010 and...ChainguardChainguard builds, secures, and maintains a catalog of hardened, minimal container images and software supp...HPE Aruba NetworkingHPE Aruba Networking is the networking business unit of Hewlett Packard Enterprise (NYSE HPE), born of Arub...WiresharkWireshark is the world's foremost and widely-used free and open-source network protocol analyzer. It lets y...SardineSardine is a San Francisco-based fraud prevention, AML compliance, and risk management platform for fintech...TradewebTradeweb Markets is a leading global operator of electronic marketplaces for rates, credit, equities, and m...Bloomberg IndicesBloomberg Indices are a comprehensive family of fixed income, equity, commodity, and multi-asset benchmark ...EcologiEcologi is a Bristol, UK climate action platform and B Corp founded in 2019 that lets individuals and busin...Bloomberg Query Language (BQL)Bloomberg Query Language (BQL) is a proprietary query language for accessing, filtering, aggregating, and c...CerteroCertero is an enterprise IT Asset Management (ITAM) software vendor whose flagship CerteroX platform unifie...Babylon.jsBabylon.js is an Apache-2.0 licensed, TypeScript-first open-source 3D engine and rendering framework sponso...AstroPayAstroPay is a Uruguay-founded fintech and electronic money institution offering a multicurrency wallet, vir...CMA CGMCMA CGM is a Marseille-headquartered French container shipping, logistics, and port operator and the third-...AutoGen StudioAutoGen Studio is a low-code / no-code developer GUI from Microsoft Research for rapidly prototyping, compo...TransDigm GroupTransDigm Group is a leading global designer, producer, and supplier of highly engineered aerospace compone...Glass HealthGlass Health is a San Francisco-based clinical AI company founded in 2021 by Dereck Paul (CEO) and Graham R...Catena-XCatena-X is the automotive industry's data space standard, published by Catena-X Automotive Network e.V. — ...
Minimal 2 Almost no public developer surface
Unrated 3 Not yet scored
CCPA (California Consumer Privacy Act)The California Consumer Privacy Act (CCPA), amended by the California Privacy Rights Act (CPRA), is a state...OctoAIOctoAI (formerly OctoML) was a Seattle-based AI inference platform founded in 2019 as a University of Washi...Test PlansStructured documentation outlining test objectives, scope, approach, resources, schedule, and deliverables ...
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.
$110B+ digital assets secured; $10B+ staked on Blockdaemon validators; 250K+ nodes launched; 80+ protocols3D 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 AssertionsAfrica's largest merchant acquirer — ~10M business and individual accounts, $17B monthly TPV, 26M daily payments processedApproval ProcessesAssertionsAssessment AccessAssessment and PlanAssessment 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)Certification: third-party conformity assessment via TÜV Rheinland and TÜV SÜDChainStream real-time streaming API — transactionsSubscribe, slotsSubscribe, blocksSubscribe over WebSocket JSON-RPC 2.0 at wss://chainstream.api.syndica.ioChannel AssemblyClaude 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 ManagementDigital Twin Manager (DTM) — asset modeling, hierarchies, computed smart functions, custom properties
Showing 40 of 118 declared variants
Work with this as data
Every feature here is available over the APIs.io API and to AI agents over MCP. Features is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.