emerging · -1.3 capability schema

Specification

Score 20.5 / 100 29 providers +48 via APIs 78 APIs Search apis.io →
Business capabilities this tag reaches
Developer Platform & API Ecosystem Management 1 Product Information Management 1
Variants seen in the corpus: SpecificationsSpecification

Providers using this tag (29)

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

Exemplar 2 Complete, well-documented, and agent-ready
gunspec-ioFirearmsDatabaseSDK1 API66.5PostmanEnvironmentFlowWorkspace21 APIs82.5
Strong 1 Solid coverage with minor gaps
GSMATelecommunicationsUnited KingdomStandardsTrade Association37 APIs58.8
Developing 4 Usable, with meaningful gaps to close
Buildpacks IoCloud Native BuildpacksContainer ImagesBuild AutomationCNCF1 API52.2AsyncAPIEvent-DrivenLinux FoundationMessagingStandards1 API45.6Hey APICode GenerationDeveloper ToolsOpenAPISDK1 API42.0AGNTCYAI AgentsInteroperabilityOpen Source4 APIs51.0
Thin 8 Limited public surface area
CloudEventsCloudEventsCloud-NativeEventGraduated1 API36.3Craft.ioProduct ManagementRoadmapsOKRsBacklog1 API32.6openEHRopenEHRHealthcareElectronic Health RecordsHealth Informatics7 APIs30.4OpenFeatureCloud-NativeFeature FlagsFeature ManagementIncubating1 API26.9AcelabCompanyConstructionArchitectureBuilding Materials2 APIs37.6Open Education APICompanyEducationHigher EducationOpen Standard2 APIs37.6Alliance for OpenUSD3DInteroperabilityLinux FoundationMetaverse2 APIs27.9Agentic Resource Discovery (ARD)Agentic Resource DiscoveryARDAI CatalogAgent Discovery1 API27.6
Emerging 9 Early or largely undocumented
APIs.jsonAPI AggregationAPI CatalogingAPI CommonsAPI Discovery1 API25.9TLA Plus FoundationFormal MethodsLinux FoundationVerification6 APIs17.8OpenAPIDocumentationREST1 API14.5FOCUS (FinOps Open Cost and Usage Specification)BillingCost and UsageFinOpsOpen Standard1 API13.0AvoiceCompanyArchitectureEngineeringAECO12.7Cap'n ProtoBinary FormatCapability-Based SecurityCode GenerationIPC5 APIs11.6OpenspecSpec-Driven DevelopmentAI Coding AssistantsDeveloper ToolsCLI23.5Open Geospatial Consortium (OGC)OGCOGC APIGeospatialGIS23 APIs20.0ASTM InternationalStandardsStandards Development OrganizationConsensus StandardsTechnical Committees2 APIs13.2
Minimal 5 Almost no public developer surface
OpenAPI InitiativeLinux FoundationStandards1 API7.3Serverless WorkflowAPI CompositionServerless1 API5.0Java EEEnterpriseJakarta EEJavaJava EE3.2Component ModelABIBytecode AllianceComponentsInterfaces4 APIs10.2EditorConfigCoding StandardsConfigurationDeveloper ToolsFile Format8.7

APIs with this tag (78)

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 8 Complete, well-documented, and agent-ready
Arazzo Specification (Redocly Tooling)Arazzo is the OpenAPI Initiative's specification for describing multi-step API workflows; Redocly is a prim...81.2Optimizely Specifications APIThe Specifications API from Optimizely — 7 operation(s) for specifications.78.1CarsXE International VIN Decoder APIVIN decoding for non-US vehicles, returning make, model, year, and market-specific trim/spec data for inter...75.6CarsXE Specifications APIVIN decoding for North American and international vehicles — 2 operations (getVehicleSpecs, getInternationa...75.6CarsXE Vehicle Specifications APIVIN decoding and comprehensive vehicle specification lookup. Returns year, make, model, trim, engine, drive...75.6Clerk OpenAPI SpecificationsPublic repository of OpenAPI specifications for Clerk's APIs, used as the source for generated SDKs and doc...73.1Autodesk ACC AutoSpecs APIThe ACC AutoSpecs API retrieves Smart Register data from specification PDFs and submittal requirements with...72.9Procore Specifications APIThe Specifications API from Procore — 43 operation(s) for specifications.68.5
Strong 7 Solid coverage with minor gaps
Aeris Specifications APISpecification Management APIs are for user to get specifications info64.0ParlayAPI Specification APIOpenAPI and AsyncAPI specs describing the REST and streaming surfaces.61.9Fusio Specification APIThe specification API from Fusio — 3 operation(s) for specification.61.0Instasent Specifications APIThe specifications API from Instasent — 4 operation(s) for specifications.60.6Jentic API AI-Readiness Framework (JAIRF)Technical specification for evaluating how interpretable, operable, and trustworthy an API is for AI system...58.9Accruent Specifications APIThe Specifications API from Accruent — 2 operation(s) for specifications.57.7CDEvents SpecificationCDEvents is a common specification for Continuous Delivery events that enables interoperability across CI/C...56.2
Developing 13 Usable, with meaningful gaps to close
Buildpack SpecificationThe Buildpack API (currently 0.12) defines the contract between an individual buildpack and the lifecycle. ...52.2Image Extension SpecificationImage extensions emit Dockerfile snippets applied by the `extender` lifecycle binary to the build and/or ru...52.2Platform SpecificationThe Platform API (currently 0.15) defines how platforms (pack, kpack, Tekton Pipelines, GitLab Auto DevOps,...52.2Cox Automotive Specifications APIThe Specifications API from Cox Automotive — 1 operation(s) for specifications.50.63GPP Forge APIThe 3GPP Forge (forge.3gpp.org) is a self-managed GitLab instance where 3GPP publishes the machine-readable...49.2Buildpack API SpecificationThe Buildpack API is the contract between a buildpack and the lifecycle. It defines the detect and build ex...49.2Distribution API SpecificationThe Distribution API specifies how buildpacks and builders are packaged as OCI artifacts, signed, and distr...49.2Platform API SpecificationThe Platform API is the contract between the CNB lifecycle and a platform such as pack, kpack, or a CI runn...49.2VTEX Specification APIThe Specification API from VTEX — 2 operation(s) for specification.47.2AsyncAPI SpecificationThe AsyncAPI Specification is an open standard for describing asynchronous and event-driven APIs. It provid...45.6HAProxy Specification APIThe Specification API from HAProxy — 1 operation(s) for specification.44.0API BlueprintAPI Blueprint is a high-level API design language created by Apiary for designing and documenting web APIs....43.1Hey API Specifications APIThe Specifications API from Hey API — 1 operation(s) for specifications.42.0
Thin 20 Limited public surface area
Acelab Material Hub Platform APIThe private production API behind the Acelab Material Hub web application and Revit add-in. It is not a pub...37.6Equipmentwatch Specifications APIThe Specifications API from Equipmentwatch — 2 operation(s) for specifications.37.2CloudEvents SpecificationThe CloudEvents specification defines a set of metadata attributes that must be present in every event, inc...36.3CloudEvents SQL (CESQL)CloudEvents SQL (CESQL) is a v1.0 specification that defines a standardized query language for filtering an...36.3OCI Spec for Rustoci-spec-rs is a Rust implementation of the OCI Runtime, Image, and Distribution Specifications, providing ...35.1THORChain Specification APIThe Specification API from THORChain — 2 operation(s) for specification.35.1Citevana APICitevana API as documented publicly: 9 operations. Contract generated from the documentation by API Evangel...32.9Traceable Specifications APIDownload OpenAPI, WSDL, and other API specification files generated from discovered traffic.32.8Notary Project Signing SpecificationThe Notary Project specification defines the signature envelope format, trust store and trust policy for co...31.6Specright APIREST API over Specright's specification data. Forty-six operations across six areas: token issuance, specif...30.5AsyncAPILinux Foundation-hosted specification for event-driven APIs. Describes servers, channels, operations, messa...29.3CloudEventsCNCF-graduated specification (graduated January 25, 2024) for describing event data in a common way. Define...29.3Kalshi AsyncAPI SpecificationMachine-readable AsyncAPI description of the Kalshi WebSocket streaming API. Suitable for generating async ...28.9Apache Arrow Format SpecificationThe Apache Arrow columnar format specification defines the binary layout for in-memory columnar data, inclu...28.5API-Fiddle Specifications APIManage API specifications within projects.27.9docomo Mail IMAP InterfaceThe docomo Mail IMAP interface is the one machine-interface specification NTT DOCOMO publishes openly, with...27.9MCP SpecificationThe authoritative protocol definition for the Model Context Protocol, maintained at modelcontextprotocol.io...26.7Trustworthy Workload Identity (TWI) SpecificationsA working group and set of Internet Draft specifications under the Confidential Computing Consortium that d...26.6W3C APIThe W3C API provides programmatic access to W3C data including specifications, working groups, editors, tra...26.3W3C Specifications APIThe Specifications API from W3C — 3 operation(s) for specifications.26.3
Emerging 27 Early or largely undocumented
APIs.json SpecificationThe APIs.json specification defines a machine-readable JSON or YAML format for describing API operations. U...25.9in-toto Attestation FrameworkThe in-toto Attestation Framework provides a specification for generating verifiable claims about any aspec...25.1in-toto Attestation SpecificationThe in-toto specification defines the metadata format for recording software supply chain steps. It include...25.1Smithy IDLThe Smithy Interface Definition Language (IDL) is a specification for defining API models using shapes and ...25.1NIST SP 800-207 Zero Trust ArchitectureThe foundational specification of the Zero Trust security model. Defines the seven tenets, the PDP/PEP/PA l...24.3TUF Repository SpecificationThe TUF specification defines the structure of update repositories including the root, targets, snapshot, a...24.3BICS Specification APIThe specification API from BICS — 1 operation(s) for specification.23.8VINaudit Specifications APIThe Specifications API from VINaudit — 1 operation(s) for specifications.23.8CNI SpecificationThe CNI specification defines the interface between container runtimes and network plugins. It specifies ho...22.9RISC-V ISA SpecificationsThe canonical RISC-V Instruction Set Architecture specifications including the Unprivileged ISA (RV32I/RV64...21.7Jakarta Bean Validation Specification 3.1The Jakarta Bean Validation 3.1 specification defines the constraint model, annotation processor, Validator...19.7TLA+ Community ModulesA curated collection of TLA+ snippets, operators, and modules contributed by the TLA+ community, providing ...17.8TLA+ Specification ExamplesA collection of TLA+ specifications of varying complexity covering distributed algorithms, consensus protoc...17.8Apache Parquet Format SpecificationThe core specification for the Parquet columnar storage format.17.6JSON:APIJSON:API is a specification for how a client should request that resources be fetched or modified, and how ...14.9OpenAPI SpecificationThe OpenAPI Specification (OAS) defines a standard, language-agnostic interface to RESTful APIs which allow...14.9FOCUS (FinOps Open Cost and Usage Specification)FOCUS defines a common normalized data schema for cloud and technology billing data. The specification is d...13.0Overture SchemaCanonical open schema specification for all Overture themes, maintained in the OvertureMaps/schema GitHub r...12.2Cap'n Proto Encoding (Wire Format)The Cap'n Proto encoding specification defines the binary wire format. The in-memory layout is the wire for...11.6Cap'n Proto RPC ProtocolCap'n Proto's RPC protocol is a capability-based RPC layer that supports promise pipelining, object referen...11.6Cap'n Proto Schema LanguageThe Cap'n Proto schema language is used to define message types in .capnp files that are then compiled into...11.6Jakarta JSON BindingJakarta JSON Binding (formerly JSON-B) is a binding framework for converting Java objects to and from JSON ...11.3Jakarta JSON ProcessingJakarta JSON Processing (formerly JSON-P) provides an API to parse, generate, transform, and query JSON doc...11.3Jakarta RESTful Web ServicesJakarta RESTful Web Services (formerly JAX-RS) is the API specification for developing web services that fo...11.3Jakarta ServletJakarta Servlet is a server-side Java API for handling HTTP requests and generating dynamic responses. It p...11.3Jakarta ValidationJakarta Validation (formerly Bean Validation) provides an object-level constraint declaration and validatio...11.3Jakarta WebSocketJakarta WebSocket defines a standard API for creating server and client endpoints that communicate using th...11.3
Minimal 3 Almost no public developer surface
WebAssembly Component Model SpecificationThe Component Model specification repository under the W3C WebAssembly Community Group. Contains design doc...10.2Margo SpecificationMargo defines an open standard specification for interoperability of edge applications, devices, and orches...9.6OpenAPI Initiative APIAPI for accessing OpenAPI Initiative resources, specifications, and tooling ecosystem documentation for def...7.3

Companies reaching this through an API (48)

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

3GPP Accruent Aeris Apache Arrow Apache Parquet API-Fiddle Apiary Autodesk Bean Validation BICS CarsXE Citevana Clerk Cloud Native Buildpacks Confidential Computing Consortium Container Network Interface (CNI) Continuous Delivery Foundation Cox Automotive Equipmentwatch Events Fusio HAProxy In-Toto Instasent Jakarta EE Jentic Kalshi Margo Model Context Protocol (MCP) Notary Project NTT Docomo Optimizely Overture Maps Foundation ParlayAPI Procore Redocly REST RISC-V International Smithy Specright The Update Framework (TUF) THORChain Traceable VINaudit VTEX W3C Youki Zero-Trust Security Model

Score breakdown

Frequency
52.7
log-scaled weighted occurrences
Breadth
0.4
spread across providers
Quality lift
29.0
mean composite of providers using it
Cohesion
9.7
strength of nearest seed neighbor

Related tags

Linux Foundation 11 co-occurrences Standards 16 co-occurrences API Design 6 co-occurrences Schema 11 co-occurrences CNCF 5 co-occurrences Go 6 co-occurrences Python 12 co-occurrences Cloud-Native 8 co-occurrences

Where this tag comes from

Api tag77
Provider tag29
Openapi tag19
Openapi op tag48

Cohort brief

Auto-generated

The 29 providers in the APIs.io catalog tagged Specification, scored on the Kin Score. Every figure below is computed from the catalog — nothing here is written.

Providers
29
all scored
Mean Kin Score
29
+4.9 vs catalog 24.1
Mean Agent Readiness
16.9
+2.8 vs catalog 14.1
Spread
3.2–82.5
median 26.9 · σ 19.3
How the 29 split by band
Exemplar 2Strong 1Developing 4Thin 8Emerging 9Minimal 5
Facet averages, against the whole catalog
FacetThis cohortCatalogDifferenceScored
Contract Quality 31.7 18.6 +13.1 29
Developer Ergonomics 35.1 24.5 +10.6 29
Operational Transparency 23 13.2 +9.8 29
Contract Governance 14.9 9.7 +5.2 29
Discoverability 61.3 59.1 +2.2 29
Access Clarity 16.4 30 -13.6 29

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) 14% 18% -4
MCP server (first-party) 14% 16% -2
Agent Skills 0% 0% 0
OAuth scopes 10% 13% -3
Security 90% 99% -9
Arazzo workflows 3% 1% +2
Governance rules 66% 36% +30

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 Postman 82.5
  2. 2 gunspec-io 66.5
  3. 3 GSMA 58.8
  4. 4 Buildpacks Io 52.2
  5. 5 AGNTCY 51
  6. 6 AsyncAPI 45.6
  7. 7 Hey API 42
  8. 8 Acelab 37.6
  9. 9 Open Education API 37.6
  10. 10 CloudEvents 36.3
Top by Agent Readiness
  1. 1 Postman 55.6
  2. 2 Craft.io 50.3
  3. 3 AGNTCY 42.5
  4. 4 GSMA 40.2
  5. 5 OpenFeature 34.5
  6. 6 gunspec-io 33.3
  7. 7 Hey API 32.4
  8. 8 Buildpacks Io 30.5
  9. 9 AsyncAPI 30.3
  10. 10 Open Geospatial Consortium (OGC) 28.5
All 29 members of this roster resolve to a scored provider in the catalog.
Coverage caveat. 23 of 29 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.

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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.
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