established · -1.5 capability schema

OpenAPI

Score 26.5 / 100 203 providers +74 via APIs 151 APIs Search apis.io →

Providers using this tag (203)

Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.

Exemplar 22 Complete, well-documented, and agent-ready
ScalarAPI ClientAPI DocumentationAPI ReferenceCode Generation2 APIs76.4StoplightAPI DesignAPI DocumentationAPI GovernanceAsyncAPI1 API74.1APIVerveAPI MarketplaceRESTJSONGraphQL1 API73.9ReadMeDocumentationDeveloper HubAPI ReferencePortal2 APIs68.8RoutebaseAPI lifecycle managementAPI DesignAPI Documentation1 API67.7APIs.ioAPI AggregationAPI DirectoryAPI DiscoveryAPI Indexing20 APIs91.9Zoho CRMCRMSalesMarketing AutomationLead Management105 APIs85.4PostmanEnvironmentFlowSpecificationWorkspace21 APIs82.5RedoclyArtificial IntelligenceAPI CatalogAPI DocumentationArazzo4 APIs81.2OpenMercantilBDNSBORMEBusiness RegistryCIF3 APIs79.40xArchiveMarket DataHistorical DataCryptocurrencyDeFi1 API74.9Tvarka ATK APIAuthenticationDigital SignatureeIDASQES4 APIs73.9CongaCompanyEnterprise SoftwareContract Lifecycle ManagementCPQ31 APIs72.7SpeakeasyArtificial IntelligenceDocumentationMCPPlatform1 API72.3ArchbeeAPI DocumentationDocumentation PlatformKnowledge BaseTechnical Writing11 APIs70.8TranscriptFetchTranscriptsSpeech-to-TextCaptionsYouTube2 APIs70.2Statable Stats APIAnalyticsWeb AnalyticsCookielessPrivacy1 API69.7RoxyAPIAstrologyVedic AstrologyNumerologyTarot2 APIs68.6StayingAPITravelHospitalityaccommodation-datahotel-api1 API68.6TaskfolkProject ManagementIssue TrackingTask ManagementProductivity2 APIs68.3Cvent Event CloudAttendee HubAttendeesBulkContacts2 APIs66.6FarmDash.oneDeFiDeFAIAI AgentsMCP6 APIs66.5
Strong 36 Solid coverage with minor gaps
Bump.shAPI ChangelogAPI DocumentationAPI HubAPI Governance1 API65.2Odds APISportsSports BettingBetting Oddsbookmaker-odds1 API64.5latitude10-techAPI PlatformMCPDeveloper ToolsAI Agents3 APIs63.7Scanverity Resolution APIPrediction MarketsResolution RiskMarket IntelligenceDue Diligence1 API60.5MediaCaption APIYouTubeTranscriptionCaptionsSubtitles1 API60.2OctriCompanyDocumentationSDK2 APIs58.4Swagger CodegenClient LibraryCode GenerationOpen Source3 APIs56.5DeveloperHubAPI ReferenceDeveloper PortalDocumentationKnowledge Base1 API65.8classifier-devCompanyMachine LearningNatural Language ProcessingClassification1 API65.4Autoderm – AI Dermatology APIdermatology-apiai-dermatologyMedical ImagingTelehealth1 API64.9NetcrackerTelecommunicationsUnited StatesBSSOSS4 APIs64.6AirOpsCompanyApplicationArtificial IntelligenceContent1 API64.5APIMaticAPI TransformationCode GenerationDeveloper ExperienceDeveloper Tools5 APIs63.2Adanos Market Sentiment APIMarketsSentimentStocksCryptocurrency7 APIs63.0AI for DatabaseArtificial IntelligenceDatabaseAnalyticsDeveloper Tools1 API62.7GeneosAPMCapital MarketsInfrastructureITRS1 API62.3CriteoAdvertisingAgent SkillsAnalyticsAudiences3 APIs62.2ReachdeskCorporate GiftingDirect MailSwagB2B1 API62.0AssetFareAI AgentsAsset TransferBridgeCross-Chain6 APIs61.9NetBox LabsCompanyNetworkingDCIMIPAM1 API61.8FusioAPI ManagementOpen SourceREST APIAPI Gateway4 APIs61.0ReefAPIWeb DataData AggregationWeb ScrapingSERP1 API60.7ETSITelecommunicationsFranceStandardsStandards Body24 APIs60.3Atmospore Pollen ForecastsWeatherPollenAllergyEnvironmental Data1 API59.0JenticAI AgentsArazzoMCP1 API58.9Observe.AICompanyAi AppsContact CenterConversation Intelligence1 API58.9EventXCompanyEvent ManagementEvent RegistrationTicketing1 API58.6symbaiex-comCompanyArtificial IntelligenceResearch3 APIs57.9InsomniaAPI DesignCLIClientsDeveloper Tools1 API57.5GZW Data APIGamingVideo Gamesgray-zone-warfareGame Data1 API56.9StotlesCompanyProcurementPublic SectorGovernment1 API56.5AmunCoreDatabaseAPI ManagementBackendNo-Code2 APIs56.2DreamThreadsdream analysisDream interpretationNatural Language Processingstructured parsing1 API55.9SweepCompanyCloudSalesforceRevenue Operations2 APIs55.7iGaming ToolsiGamingOnline CasinoGamblingslot games1 API55.5BlngCompanyJewelryGenerative AIDesign3 APIs54.8
Developing 47 Usable, with meaningful gaps to close
workwing-ioField Service ManagementSoftware-as-a-ServiceMobile1 API52.7LiblabSDKSDK GenerationCode Generation13 APIs50.3SwaggerHubAPI DesignAPI ManagementAPI RegistryDeveloper Tools2 APIs47.2Kubb StudioCompanyCode GenerationTypeScript2 APIs47.0KiotaCode GenerationMicrosoftSDK1 API46.6TROLIECompanyEnergyElectric GridTransmission1 API45.6gaipagents-comCompanyArtificial IntelligenceAI AgentsMCP1 API43.8OpenAPI GeneratorCode GenerationDocumentationOpen Source1 API42.5Hey APICode GenerationDeveloper ToolsSDK1 API42.0ReadMe.ioCompanyDocumentationAPI DocumentationDeveloper Experience3 APIs41.6ZallyAPI DesignAPI LintingAPI QualityOpen Source1 API40.4RittenCompanyBehavioral HealthElectronic Health RecordsHealthcare1 API54.2StainlessCode GenerationDocumentationDeveloper ExperienceMCP2 APIs53.6signalaf-comArtificial IntelligenceAnalyticsLeaderboards1 API53.3MagniteAdvertisingProgrammatic AdvertisingSell-Side PlatformSupply Side Platform4 APIs53.0OpalCompanyConsumerMarketingContent Planning3 APIs52.3gadgethumans-comAI ToolsRemote WorkDeveloper APIsUtilities2 APIs52.0Workday BenefitsBenefitsHuman ResourcesHCMEnterprise4 APIs51.8AGNTCYAI AgentsInteroperabilitySpecificationOpen Source4 APIs51.0anewHTMLWebpageWebsitesURLs1 API50.7GeoloodsGeocodingPlace SearchLocationCoordinates1 API50.5Loa Healthcare Pricing APIHealthcarePrice Transparencymedical pricingHospitals1 API49.7ElvaAPI ManagementMCP ServerMCP LogsMCP Insights1 API49.43GPPTelecommunicationsGlobalStandardsStandards Body116 APIs49.2한국주식데이터 (aikstockdata)South KoreaStock MarketFinancial DataOpen Data2 APIs49.1Agentic AtlasAgentic SystemsAI PatternsMCP1 API49.0QR Code CrafterQR CodesQR Code GenerationStatic QrDynamic QR1 API49.0DatabookCompanyVertical SoftwareSales IntelligenceAccount Intelligence1 API48.1BomboraIntent DataB2B IntentCompany SurgeAccount Based Marketing6 APIs47.2BTC War Live Market Data APIFinanceCryptocurrencyMarket DataBitcoin2 APIs47.2Sovereign European Cloud API (SECA)CompanyCloudCloud InfrastructureSovereignty12 APIs47.0PurplebricksReal EstateUnited KingdomProperty ListingsOnline Estate Agency18 APIs46.3santosautomation-comArtificial IntelligenceAutomationWebsite IntelligenceAgent Readiness1 API45.3TradeDataHub Public APIcontractor dataB2B DataBusiness ListingsDatasets1 API43.5AdsmomCompanyAdvertisingAd IntelligenceCompetitive Intelligence1 API43.3WAODAOAI AgentsArtChainHuman and AINFT Metadata3 APIs43.0MSP SoftwareDirectoryMSPSoftwareComparison1 API42.8Vehicles.devAutomotiveVehicle DataVIN DecodingVehicle Valuation1 API42.6CrosstabsStatisticsData AnalysisFree Tools1 API42.3LimitlessArtificial IntelligenceWearablesPendantMeeting Notes1 API42.0Rocket LawyerLegalLegal TechLegal DocumentsE-Signature4 APIs41.3Rugspull Read APIBNB Smart ChainBSCwbnbRead Only1 API41.1MerQubeCompanyFinancial ServicesIndex DataMarket Data3 APIs40.7FintaryCompanyFintechInsuranceInsurtech4 APIs40.3The Holistic Care — THC Open Mindfulness APIMindfulnessEducationHealth2 APIs40.3Agent CommonsArtificial IntelligenceAgentsCollaborationEvidence1 API39.9StatOriginCompanyDataStatistics1 API39.3
Thin 46 Limited public surface area
OrvalCode GenerationSwaggerSDK1 API38.9AbuzzHiveArtificial IntelligenceAgentsPlatform1 API38.2datamcpDatabaseMCPArtificial Intelligence1 API38.0OgenCode GenerationGoSDK1 API37.0TypeSpecAPI DesignCode GenerationDeveloper Tools6 APIs35.7FernAPI LifecycleSDK GenerationClient LibraryAPI Documentation1 API35.0AutoRestCode GenerationMicrosoftSDK Generation6 APIs34.8pyungyo-comCompanyTelecommunicationsMobileSouth Korea1 API34.6Refitter.NETC#Code Generation2 APIs34.3CuratorSearchAgent-NativeMCPLlms.txt1 API34.1Oapi-CodegenCode GenerationDeveloper ToolsGo1 API32.7APIs.guruAPI CatalogAPI DirectoryAPI DiscoveryCommunity1 API31.6SchemathesisAPI TestingContract TestingDeveloper ToolsFuzzing1 API31.1BetTip Draws APILottery resultsUK49sGoslotoSA National Lottery1 API29.3API-FiddleAPI DesignCollaborationDocumentation1 API27.9OpenAPI TypeScript CodegenCode GenerationSwaggerSDK1 API27.3Stoplight ElementsAPI DocumentationDeveloper ToolsDocumentationInteractive Docs1 API26.8ArclanCompanyRegistryMCP1 API26.2SpecwayAPI DocumentationDeveloper ToolsAI IntegrationInteractive Docs1 API39.1Casey's General StoresAzure API ManagementConexxusConvenience StoresFood Service21 APIs39.0KagiSearchPremium SearchAI SearchSummarization1 API38.8Lunch FlowFintechBankingIntegration1 API38.7Country Calling CodesDataReferenceTelecommunicationsPhone1 API38.5BotFriendlyBotFriendlyAI AgentsMachine-to-MachineAPI Directory1 API38.3Politecnico di TorinoEducationHigher EducationUniversityTechnical University3 APIs38.2programmes-netCompanyDeveloper ToolsMCP3 APIs37.9PatchClimateCarbon CreditsCarbon RemovalOffsets2 APIs37.7Fluid RecallArtificial IntelligenceEducationFree1 API37.6CharmnomiconCommunityArtificial IntelligenceWeb App1 API36.8BestPrintOnDemandCompanyPrint on DemandPricing1 API36.4BotGatheringArtificial IntelligenceBotRecipesPlatform2 APIs36.4logicnodes-ioCompanyBlockchainArtificial IntelligenceGas Prices1 API35.2Awesome ToolsSoftware DirectoryAI ToolsSoftware-as-a-ServiceReviews1 API33.6The HiveArtificial IntelligenceCoordinationAgentsPublic1 API33.6CR8 Agent CommonsCompanyAI AgentsMessage BoardMCP1 API33.1AINumbers.coFintechPaymentsCompliance1 API32.4CyberArkAuthenticationCloud SecurityConjurCredential Vault1 API32.4Ecom Image OptimizerImage OptimizationE-CommerceFree1 API31.9RapiDocDocumentationPlatformWeb Components1 API31.8ApicurioApache LicenseAPI DesignAPI RegistryAvro1 API31.7CAMARA ProjectAPI StandardsCAMARAGSMAGSMA Open Gateway24 APIs29.7Serbia Company DataSerbiaCompany DataBusiness RegistryOpen Data1 API29.6moradas-devAddressPortugalAutocomplete1 API29.3Hanyang UniversityEducationHigher EducationUniversitySouth Korea1 API28.8DoctaveDocumentationPlatformPortal1 API28.242CrunchAPI SecurityPlatformScanningSecurity6 APIs26.7
Emerging 42 Early or largely undocumented
EntityIndex.aiHotelsRestaurant1 API24.3openapi-comAPI MarketplaceB2BData ServicesIntegration23.8NSwag.NETASP.NET CoreC#Code Generation1 API23.7ReDocAPI DocumentationDeveloper ToolsDocumentation1 API23.7Manage OpenAPI via GitHub DemoAPIs.jsonDemoGitHub1 API23.1NexonCompanyConsumerGamingVideo Games1 API22.7OpticAPI GovernanceBreaking ChangesContract TestingDiff1 API21.8VacuumAPI DesignDocumentationLinting1 API21.6stackgems-comCompanyDeveloper ToolsCatalogAgent-Operated1 API20.4SpectralAPI DesignAPI LintingAPI Style GuideAsyncAPI1 API19.5ieUnitFinanceCryptocurrencyPrecious Metals2 APIs19.0ApiNotesAPI ReferenceDeveloper PortalDeveloper ToolsDocumentation1 API16.8SpecLynxAPI DesignAsyncAPIDeveloper ToolsJSON Schema6 APIs16.0DapperDoxAPI ReferenceDocumentationDeveloper ToolsOpen Source1 API14.9ConnexionAPI DesignASGIDesign-FirstDeveloper Tools2 APIs13.2KonfigSDK GenerationClient LibraryAPI DocumentationDeveloper Tools5 APIs12.0MetloAPI SecurityCloud-NativeReal-Time Monitoring1 API25.6CablesMCP ServerAgent-Nativex402Pay-per-call1 API25.4HivepostsCompanyArtificial IntelligenceForumsSolutions1 API25.3gregbenza-aiCompanyArtificial IntelligenceAgents1 API24.9CarChatCompanyMarketplaceAutomotiveArtificial Intelligence1 API24.8An API of Ice and FireGame of ThronesASOIAFA Song of Ice and FireBooks2 APIs24.5Schwarz ITCompanyAPI GovernanceAPI LintingSpectral1 API23.8stitchapi-devCompanyIntegrationTypeScriptNode.js4 APIs23.7ThirdWatchAPI MonitoringOAuthJWT1 API23.1NMFTAAPI StandardsDSDCDigital FTL CouncilDigital LTL Council6 APIs21.4402MCP.orgPaymentsArtificial IntelligenceAgentsRegistry21.2CoupangCancellationE-CommerceSouth KoreaMarketplace1 API20.9apished-comCompanyModularMCP1 API19.9Agent SwitchboardArtificial IntelligenceDirectoryAgentsMCP1 API17.8DreddContract TestingAPI TestingAPI Blueprint1 API16.9Agentic EnterprisesBeveragesB2BMarketplaceArtificial Intelligence1 API16.5CrowCompanyArtificial IntelligenceAI AgentsMCP1 API16.2D FetcherVitamin DHealthCalculator2 APIs15.8FastAPIAsyncHigh PerformancePydantic1 API15.5Gavelin.aiGovernmentDataTranscriptsSearch15.2JD TechnologyCompanyTechnologyCloudCloud Computing1 API14.3island.is (Digital Iceland)Digital GovernmentGraphQLX-Road2 APIs13.4Aviado AIArtificial IntelligenceHealthSupplementsMCP1 API12.3Break RoomGamingArtificial IntelligenceAgentsMultiplayer1 API12.0MarandCompanyTelecommunicationsBusiness Support SystemsBSS11.5Catena-XAPI StandardsAsset Administration ShellAutomotiveCatena-X11.0
Minimal 10 Almost no public developer surface
PortmanContract TestingPostmanTesting1 API10.5API InsightsAI-ReadinessAnalysisAnalyticsAPI Design1 API8.5humanmcp-netCompanyHumanMCP1 API7.9OasdiffBreaking ChangesChangelogDeprecation1 API7.5API DefectsDefectsMonitoringQualityDocumentation1 API3.9MyriadCompanyFinancial ServicesFintechPayments1.9JargonAPI DesignData ModellingDomain-Driven DesignDomains1 API8.9HuntPriceCompanyGroceryPrice ComparisonCanada1 API7.9Agent ObservatoryArtificial IntelligenceConversationsPublic APIsAgents6.6Arista NetworksCompanyNetworkingCloudEnterprise2.2

APIs with this tag (151)

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 36 Complete, well-documented, and agent-ready
CData Open APIThe Open API API from CData — 1 operation(s) for open api.84.0Arazzo Specification (Redocly Tooling)Arazzo is the OpenAPI Initiative's specification for describing multi-step API workflows; Redocly is a prim...81.2Redocly CLIRedocly CLI is an open-source command-line tool for working with OpenAPI descriptions, developer portals, a...81.2Redocly RedocRedoc is the open-source engine that renders API reference documentation from OpenAPI definitions with a th...81.2Snyk Open APIThe OpenAPI specification for this service.80.8Scalar API ClientScalar API Client is a fully open-source, offline-first REST API client built on the OpenAPI standard. Supp...76.4Scalar API ReferencesScalar API References renders modern, interactive API documentation from OpenAPI and Swagger specifications...76.4Scalar CLIThe Scalar CLI is a command-line interface for managing OpenAPI files, generating documentation, running mo...76.4Scalar RegistryScalar Registry provides centralized management and versioning of OpenAPI Documents, JSON Schemas, and Spec...76.4Stoplight CLIThe Stoplight CLI enables programmatic linting of API descriptions and pushing analysis results to the Stop...74.1Stoplight ElementsElements is an open-source toolkit for building beautiful, interactive API documentation from OpenAPI speci...74.1Stoplight PlatformStoplight Platform is a SaaS collaborative API design and documentation management tool providing a visual ...74.1Stoplight PrismPrism is an open-source HTTP mock and proxy server that turns any OpenAPI v2/v3 or Postman Collection file ...74.1Stoplight SpectralSpectral is an open-source JSON and YAML linter for creating automated API style guides and governance rule...74.1Stoplight StudioStoplight Studio is the visual API design and technical writing editor included in the Stoplight Platform. ...74.1APIVerve GraphQL API (alpha)Single GraphQL endpoint that fans out to multiple APIs in one request. Explicitly labeled alpha / not for p...73.9APIVerve MCP ServerHosted remote MCP server (streamable HTTP) exposing every catalog endpoint as individual MCP tools with inp...73.9Tvarka Sign APIMachine channel for Tvarka Sign: post a document and a list of signers and Tvarka runs its ordinary qualifi...73.9Act! Web APIJSON-based REST API for the Act! CRM database exposing contacts, companies, groups, opportunities, tasks, a...73.7Power Platform Connectors APIAPI for custom and certified connectors that extend Power Platform capabilities across Power Apps, Power Au...73.5Clerk OpenAPI SpecificationsPublic repository of OpenAPI specifications for Clerk's APIs, used as the source for generated SDKs and doc...73.1Zuplo Open APIThe Open API API from Zuplo — 1 operation(s) for open api.72.8Speakeasy Contract TestingAPI contract test generation using OpenAPI specs and the Arazzo specification. Generates both test code and...72.3Speakeasy DocsMDGenerate beautiful API documentation from OpenAPI specs. Automatic synchronization keeps docs current with ...72.3Speakeasy MCP Server GenerationGenerate production-ready MCP server code from OpenAPI specifications. Deploy on your own infrastructure, c...72.3Speakeasy SDK GenerationGenerate idiomatic, type-safe SDKs in 7+ languages from OpenAPI specs. Supports TypeScript, Python, Go, Jav...72.3Speakeasy Terraform GenerationTurn your OpenAPI spec into a production-ready Terraform provider without the manual work. Automatically ke...72.3GitBook Open APIThe OpenAPI endpoints let you integrate your existing or newly generated OpenAPI definitions into GitBook. ...71.5Journey Planner (GraphQL)Core journey planning service built on OpenTripPlanner, providing departure boards for individual stops and...70.5Mobility (GraphQL)Aggregation service for shared mobility data in Norway: real-time information about shared bikes, e-scooter...70.5Vehicle Positions (GraphQL)GraphQL service providing real-time positions and status for public transport vehicles across Norway, inclu...70.5StayingAPI Agent SkillsPublished portable SKILL.md agent skill in the stayingapi/travel-skills GitHub repo, referenced from the SD...68.6StayingAPI MCP ServerHosted MCP server (Streamable HTTP, OAuth 2.1/PKCE) exposing 7 read-only tools mapping 1:1 to the REST endp...68.6Agorapulse Open APIThe Open API API from Agorapulse — 0 operation(s) for open api.68.4Treblle API DocumentationTreblle API Documentation automatically generates real-time API documentation from live API traffic and SDK...67.4Treblle API InsightsTreblle API Insights is a free governance tool that evaluates OpenAPI specifications, providing scores from...67.4
Strong 19 Solid coverage with minor gaps
DeveloperHub Documentation PlatformDeveloperHub provides a hosted platform for creating developer documentation including API references auto-...65.8APIMatic API Transformer APIAPIMatic API Transformer converts API definition files between more than 15 supported API specification for...63.2Custom Connectors APICustom connectors allow you to create wrappers around REST or SOAP APIs for use in Power Apps, Power Automa...63.2Onshape Open APIGet the OpenAPI specification for the Onshape API.62.7APIContext Open APIOpenAPI validation61.2ReefAPI MCP ServerHosted MCP server over streamable-HTTP with 5 discovery-first tools (search_engines, get_catalog, get_engin...60.7Agent Disco Open APIOpenAPI60.2Cisco Intersight Open APIThe Open API API from Cisco Intersight — 10 operation(s) for open api.60.1IBM WebSphere Open APIMicroProfile OpenAPI documentation endpoints59.8Arazzo EngineOpen-source Python engine that executes Arazzo workflow specifications alongside OpenAPI operation definiti...58.9Commentary Open APIThe Open API API from Commentary — 2 operation(s) for open api.58.5Octri Platform APIOctri's platform API powers the hosted products described at octri.dev — API Studio, SDK Studio, Monitoring...58.4Dream Sports Open APIThe Open API API from Dream Sports — 1 operation(s) for open api.57.7Corva Data APIThe Corva Data API serves the records stored in Corva datasets — one-second operational data, engineering c...57.6DEV Community Open APIThe Open API API from DEV Community — 1 operation(s) for open api.57.4Windmill Open APIThe Open API API from Windmill — 2 operation(s) for open api.57.3iGaming Tools MCP ServerFree public hosted MCP server (Streamable HTTP, no API key, read-only, not metered) exposing the same iGami...55.5Logius OpenAPI APIThe Openapi API from Logius — 1 operation(s) for openapi.55.5Bloomberg BLPAPI CoreThe Bloomberg Open API (BLPAPI) Core — the foundational service-oriented, socket-based API used by the Desk...55.4
Developing 22 Usable, with meaningful gaps to close
MuleSoft Anypoint Design Center APIThe Anypoint Design Center API provides access to the MuleSoft web-based API design environment for creatin...53.8Stainless Open APIThe Open API API from Stainless — 1 operation(s) for open api.53.6Truepill Open APIThe Open Api API from Truepill — 2 operation(s) for open api.53.3Duve APIDuve API as documented publicly: 17 operations. Contract generated from the documentation by API Evangelist...52.7Liblab MCP GeneratorGenerates a complete Model Context Protocol (MCP) server from an OpenAPI, Swagger, or Postman spec so AI ch...50.3Liblab Open APIThe Open API API from Liblab — 2 operation(s) for open api.50.3Liblab SDK GeneratorCloud-based generator that produces customizable, type-safe SDKs in seven target stacks (TypeScript, Python...50.3VMware Cloud Director OpenAPIModern RESTful API for VMware Cloud Director defined using OpenAPI standards providing cloud service delive...49.8Loa Healthcare Pricing MCP ServerHosted/remote MCP server 'LOA Healthcare Pricing' v1.0.0 over Streamable HTTP with 12 tools for CPT search,...49.7NetScaler Next-Gen APINetScaler Next-Gen API is a modern declarative RESTful API built on the OpenAPI 3.0 specification that allo...49.6Piknik.Spot Open APIThe Open API API from Piknik.Spot — 2 operation(s) for open api.49.5Spec Scoring APIPublic, no-auth REST API for scoring OpenAPI documents. GET /api/review/checks returns the full set of chec...49.4Zilla MCP GatewayThe Zilla MCP Gateway is the AI-facing face of the Zilla engine. It terminates Model Context Protocol Strea...49.43GPP Forge APIThe 3GPP Forge (forge.3gpp.org) is a self-managed GitLab instance where 3GPP publishes the machine-readable...49.2KiotaKiota generates strongly-typed, lightweight API clients from OpenAPI descriptions in C#, Dart, Go, Java, PH...46.6AlgoVault APIAlgoVault API as documented publicly: 18 operations. Contract generated from the documentation by API Evang...44.2Ignition Gateway REST APIThe Ignition Gateway REST API (available in Ignition 8.3+) provides an OpenAPI- compliant HTTP interface to...43.4Quady3D AI Open APIThe Open API API from Quady3D AI — 1 operation(s) for open api.43.3Weidmüller Open APIAPI for reading the OpenAPI specification42.9Hey API Openapi-Ts@hey-api/openapi-ts is an OpenAPI to TypeScript code generator that emits production-grade SDKs, types, val...42.0OWASP ZAP Open APIThe Open API API from OWASP ZAP — 2 operation(s) for open api.39.8Trieve REST APIProduction REST API for Trieve Cloud. Organizes resources around organizations, datasets, chunks, chunk gro...39.5
Thin 37 Limited public surface area
Casey's General Stores Open APIThe Open API API from Casey's General Stores — 2 operation(s) for open api.39.0X-Road (NIIS) Open APIThe Open API API from X-Road (NIIS) — 1 operation(s) for open api.38.9Duckhub Open APIThe Open API API from Duckhub — 1 operation(s) for open api.38.7Twenty Open APIOpenAPI schema discovery38.5HostTracker APIHostTracker API as documented publicly: 33 operations. Contract generated from the documentation by API Eva...38.1Kareo Clinical Open APIThe Kareo Clinical Open API provides REST-based access to EHR clinical data, exposing patient clinical reco...37.5OgenThe ogen code generator. Invoked as a build-time CLI against a local OpenAPI v3 document — `ogen [options] ...37.0Restate Open APIThe Open API API from Restate — 1 operation(s) for open api.35.7TypeSpec OpenAPI EmitterThe TypeSpec OpenAPI emitter converts TypeSpec definitions to OpenAPI 3.0 specifications. It supports HTTP ...35.7AutoRest CoreThe AutoRest Core package (@autorest/core) is the central engine that orchestrates code generation from Ope...34.8Garmo Labs APIGarmo Labs API as documented publicly: 21 operations. Contract generated from the documentation by API Evan...34.5RefitterRefitter is a .NET source generator and CLI tool that produces Refit HTTP client interfaces from OpenAPI 2....34.3agentleFS APIagentleFS API as documented publicly: 21 operations. Contract generated from the documentation by API Evang...33.9Mosaic Open APIThe Mosaic Open API exposes the workforce, project, and financial data Mosaic manages so firms can build cu...33.3Xano Generated User APIsThe REST APIs that Xano users build visually. Each API group is served at its own /api:{token} path on the ...32.8Hiasynth AB APIHiasynth AB API as documented publicly: 9 operations. Contract generated from the documentation by API Evan...32.7Oapi-CodegenCommand-line tool and Go library that converts OpenAPI 3.0 and 3.1 specifications into Go server-side, clie...32.7NASA Earthdata Open APIThe Open API API from NASA Earthdata — 1 operation(s) for open api.32.5Ambassador Blackbird API Development PlatformBlackbird is an API development platform that helps developers design, build, test, and manage APIs with AI...31.8Ambassador Edge Stack Developer PortalThe Ambassador Edge Stack Developer Portal automatically detects and publishes API documentation, serving a...31.8Apicurio CodegenApicurio Codegen generates Java JAX-RS server stubs and client code from OpenAPI specifications, enabling d...31.7Apicurio Data ModelsApicurio Data Models is a Java and TypeScript library for parsing, validating, and manipulating OpenAPI and...31.7Apicurio RegistryApicurio Registry is a high-performance, runtime registry for schemas and API designs. It stores and manage...31.7Apicurio StudioApicurio Studio is a visual, zero-code API design tool for creating and editing OpenAPI and AsyncAPI specif...31.7SchemathesisSchemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and ...31.1Expense Budget Tracker APIExpense Budget Tracker API as documented publicly: 12 operations. Contract generated from the documentation...31.0UNIverse Research Information System APIThe REST backend of UNIverse (universe.unibas.ch), the University of Basel's research information system, a...30.9Vert.x OpenAPIVert.x OpenAPI provides OpenAPI 3.1 specification support for Vert.x, enabling contract-driven API developm...30.8Hanyang University Open API Developer CenterHanyang University's own Open API platform, built and run by the university rather than bought from a vendo...28.8LayerZero Open APIThe Open API API from LayerZero — 1 operation(s) for open api.28.0Lumen OpenAPI Services (Level 3 legacy)The Level 3 / Lumen OpenAPI Services portal provided OpenAPI-described REST services such as the Lumen Loca...27.9Morgan Stanley API Platform (REST)The institutional REST APIs on the Morgan Stanley API Platform let onboarded clients and third-party partne...27.7Bezal Open APIThe Open API API from Bezal — 1 operation(s) for open api.27.5Quarkus Open APIThe Open API API from Quarkus — 2 operation(s) for open api.27.042Crunch API Security AuditThe 42Crunch API Security Audit performs automated static analysis of API definitions (OpenAPI 2, 3.0, 3.1 ...26.7Kubescape In-Cluster Component API (Open Source)The open-source Kubescape Operator's in-cluster components (storage, kubevuln, gateway, operator, node-agen...26.7flomailr APIflomailr API as documented publicly: 31 operations. Contract generated from the documentation by API Evange...26.3
Emerging 33 Early or largely undocumented
Open Charge Map Open APIThe Open API API from Open Charge Map — 1 operation(s) for open api.25.7Sourcegraph REST APIVersioned external REST API introduced in Sourcegraph 7.0 and intended as the stable integration surface go...25.5Filecoin HTTP REST APIOpenAPI-specified HTTP REST interface for Filecoin nodes, covering chain resources (tipsets, blocks, execut...24.6what3words API Docs and OpenAPI RepositoryPublic repository hosting the OpenAPI specification, LLM files, and reference material for the what3words P...24.6Track Open APIThe Open API API from Track — 1 operation(s) for open api.24.4NSwagNSwag is an open source .NET toolchain for generating C# and TypeScript API clients and Swagger/OpenAPI spe...23.7ReDocReDoc is an open-source API documentation renderer for OpenAPI specifications, originally created by Rebill...23.7NEXON Open APIProgrammatic access to per-game data (character, ranking, match, and metadata) for Nexon titles. Authentica...22.7Chainguard Unified API SpecThe unified Chainguard API specification combines API v1 and v2 definitions in a single reference, useful f...21.9Helidon Open APIThe Open API API from Helidon — 1 operation(s) for open api.21.9Optic CLIThe Optic CLI provides OpenAPI diffing, linting and breaking-change detection from the command line, compar...21.8VacuumVacuum is the world's fastest OpenAPI linter written in Go. It processes API specifications at lightning sp...21.6Coupang Open APIThe Coupang Open API is a RESTful seller (vendor) API for managing the full marketplace lifecycle including...20.9FastMCP OpenAPI and FastAPI IntegrationFastMCP can generate an MCP server directly from an existing OpenAPI 3.x description or a FastAPI applicati...19.5SpectralSpectral is a flexible JSON/YAML linter and style guide enforcer with built-in support for OpenAPI (v3.1, v...19.5Flotiq APIAuto-generated RESTful and GraphQL APIs derived from user-defined content type definitions, enabling full C...17.9DreddDredd is a language-agnostic command-line tool for validating an API description document against a backend...16.9OpenAPI VersioningOpenAPI handles versioning through the info.version field (using SemVer), the deprecated flag on individual...16.1SpecLynxStop wrestling with OpenAPI specs. SpecLynx OpenAPI Toolkit delivers the most effective way to author and m...16.0SpecLynx ApiDOMA unified semantic parsing engine that underpins all SpecLynx products. ApiDOM parses OpenAPI, AsyncAPI, Ar...16.0SpecLynx CLIA command-line interface for overlay operations, dereferencing, bundling, format conversion (JSON/YAML), an...16.0SpecLynx EditorA browser-based OpenAPI editor with real-time validation, smart autocompletion, and live preview. No instal...16.0SpecLynx Language ServiceAn LSP-compatible npm library (@speclynx/apidom-ls) providing 13 intelligent editing capabilities for API d...16.0SpecLynx OpenAPI ToolkitA VS Code extension providing semantic editing, real-time validation, linting, and live preview for OpenAPI...16.0FastAPI FrameworkModern, fast web framework for building APIs with Python based on standard Python type hints.15.5ISO 20022 API Resources CatalogueThe ISO 20022 API Resources Catalogue, governed by the API Standards Evaluation Group (APISEG), provides re...15.0DapperDoxDapperDox is an open-source API documentation generator that renders beautiful, customizable reference docs...14.9OpenAPI SpecificationThe OpenAPI Specification (OAS) defines a standard, language-agnostic interface to RESTful APIs which allow...14.9OpenAPI SpecificationThe OpenAPI Specification (OAS) defines a standard, programming language-agnostic interface description for...14.5JD Cloud OpenAPIJD Cloud OpenAPI is the programmatic control plane for JD Technology's public cloud — compute (VM), storage...14.3LoopBackLoopBack is a highly extensible Node.js and TypeScript framework for building APIs and microservices with b...14.1X-Road (Straumurinn) API CatalogueIceland's X-Road data-exchange layer (Straumurinn). Government-to-government REST services that publish Ope...13.4Connexion Python FrameworkConnexion is a contract-first Python web framework that loads an OpenAPI specification and routes requests ...13.2
Minimal 4 Almost no public developer surface
PortmanPortman is an open source CLI tool that auto-generates Postman collections with contract and variation test...10.5API Insights AnalysisAPI Insights analyzes OpenAPI specifications (OAS v3, JSON or YAML) and produces detailed scorecards across...8.5OasdiffOasdiff is an open-source tool for detecting breaking changes and generating changelogs from OpenAPI specif...7.5FastAPIModern, fast web framework for building APIs with Python 3.7+.7.4

Companies reaching this through an API (74)

These companies publish an API, specification or operation carrying “OpenAPI” 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.

Act! CRM Agent Disco agentleFS Agorapulse Aklivity AlgoVault Ambassador APIContext Bezal Bloomberg CData CenturyLink (Lumen Technologies) Chainguard Cisco Intersight Citrix NetScaler Clerk Commentary Corva AI DEV Community Dream Sports Duckhub Duve Entur Expense Budget Tracker FastMCP Filecoin flomailr Flotiq Garmo Labs GitBook Helidon Hiasynth AB HostTracker IBM WebSphere Inductive Automation ISO 20022 Kareo Kubescape LayerZero Logius Microsoft Power Apps Microsoft Power Platform APIs Morgan Stanley Mosaic MuleSoft NASA Earthdata Onshape Open Charge Map OpenAPI OpenJS Foundation
Show all 74 companies ↓
OWASP ZAP Piknik.Spot Python Standard Library and Popular Quady3D AI Quarkus REST Restate Snyk Sourcegraph Track Treblle Trieve Truepill Twenty University of Basel Versioning Protocols Vert.x VMware Weidmüller what3words Windmill X-Road (NIIS) Xano Zuplo

Score breakdown

Frequency
65.2
log-scaled weighted occurrences
Breadth
2.6
spread across providers
Quality lift
41.4
mean composite of providers using it
Cohesion
8.6
strength of nearest seed neighbor

Related tags

Documentation 34 co-occurrences API Design 20 co-occurrences API Documentation 19 co-occurrences Code Generation 21 co-occurrences SDK Generation 17 co-occurrences Llms.txt 18 co-occurrences JSON Schema 12 co-occurrences Developer Tools 61 co-occurrences

Where this tag comes from

Provider tag203
Api tag143
Openapi tag40
Openapi op tag62

Cohort brief

Auto-generated

The 189 providers in the APIs.io catalog tagged OpenAPI, scored on the Kin Score. Every figure below is computed from the catalog — nothing here is written.

Providers
189
of 203 in the catalog
Mean Kin Score
41.9
+17.8 vs catalog 24.1
Mean Agent Readiness
28.7
+14.6 vs catalog 14.1
Spread
3.9–91.9
median 40.3 · σ 19.1
How the 189 split by band
Exemplar 22Strong 32Developing 44Thin 45Emerging 39Minimal 7
Facet averages, against the whole catalog
FacetThis cohortCatalogDifferenceScored
Contract Quality 40.7 18.6 +22.1 189
Developer Ergonomics 45.5 24.5 +21 189
Operational Transparency 29.4 13.2 +16.2 189
Contract Governance 22.2 9.7 +12.5 189
Access Clarity 40.6 30 +10.6 189
Discoverability 68.2 59.1 +9.1 189

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
ArtifactThis cohortCatalogDifference
MCP server (any) 47% 18% +29
MCP server (first-party) 48% 16% +32
Agent Skills 0% 0% 0
OAuth scopes 22% 13% +9
Security 98% 99% -1
Arazzo workflows 4% 1% +3
Governance rules 78% 36% +42

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. 1 APIs.io 91.9
  2. 2 Zoho CRM 85.4
  3. 3 Postman 82.5
  4. 4 Redocly 81.2
  5. 5 OpenMercantil 79.4
  6. 6 Scalar 76.4
  7. 7 0xArchive 74.9
  8. 8 Stoplight 74.1
  9. 9 APIVerve 73.9
  10. 10 Tvarka ATK API 73.9
Top by Agent Readiness
  1. 1 APIs.io 79.5
  2. 2 Taskfolk 69.1
  3. 3 0xArchive 67
  4. 4 classifier-dev 65.2
  5. 5 Stotles 65
  6. 6 DeveloperHub 60.5
  7. 7 StayingAPI 60.2
  8. 8 Loa Healthcare Pricing API 60
  9. 9 Archbee 59.3
  10. 10 Statable Stats API 58.5
All 203 members of this roster resolve to a provider in the catalog; 189 carry a score (93%). The figures above describe the scored members only.
Coverage caveat. 105 of 189 scored members had under half their catalog-attributable points satisfied at all (catalog_earned / catalog_max < 0.5). They are INCLUDED in the mean above. A large share here means the cohort mean is partly a measurement of how far our enrichment reached, not only of how these providers publish.Generated from the catalog build of 14 November 2026, across 41591 providers, using the same computation served by the APIs.io cohort API. Briefs are published for rosters of 5 or more scored providers; below that a distribution is not meaningful.

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

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