emerging · 0.1 capability schema

Specification

Score 22.6 / 100 32 providers +45 via APIs 76 APIs Search apis.io →
Business capabilities this tag reaches
Product Information Management 1
Variants seen in the corpus: SpecificationsSpecification

Providers using this tag (30)

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

Exemplar 1 Complete, well-documented, and agent-ready
PostmanEnvironmentFlowWorkspace21 APIs79.6
Developing 6 Usable, with meaningful gaps to close
GSMATelecommunicationsUnited KingdomStandardsTrade Association37 APIs53.8Buildpacks IoCloud Native BuildpacksContainer ImagesBuild AutomationCNCF1 API53.4AGNTCYAI AgentsInteroperabilityOpen Source4 APIs48.4AsyncAPIEvent-DrivenLinux FoundationMessagingStandards1 API45.7Hey APICode GenerationDeveloper ToolsOpenAPISDK1 API42.8Craft.ioProduct ManagementRoadmapsOKRsBacklog3 APIs39.5
Thin 6 Limited public surface area
AcelabCompanyConstructionArchitectureBuilding Materials2 APIs38.2CloudEventsCloudEventsCloud-NativeEventGraduated1 API37.6Alliance for OpenUSD3DInteroperabilityLinux FoundationMetaverse2 APIs29.8APIs.jsonAPI AggregationAPI CatalogingAPI CommonsAPI Discovery1 API28.2OpenFeatureCloud-NativeFeature FlagsFeature ManagementIncubating1 API28.0openEHRopenEHRHealthcareEHRElectronic Health Records13 APIs27.0
Emerging 12 Early or largely undocumented
Agentic Resource Discovery (ARD)Agentic Resource DiscoveryARDAI CatalogAgent Discovery1 API23.5OpenspecSpec-Driven DevelopmentAI Coding AssistantsDeveloper ToolsCLI20.2TLA Plus FoundationFormal MethodsLinux FoundationVerification6 APIs19.2Spotlight RulesAPI GovernanceAPI LintingSpectralRulesets18.4Open Geospatial Consortium (OGC)OGCOGC APIGeospatialGIS24 APIs17.8OpenAPIDocumentationREST1 API17.0FOCUS (FinOps Open Cost and Usage Specification)BillingCost and UsageFinOpsOpen Standard1 API15.7GraphQLData FetchingGraphQLQuery Language14.8Cap'n ProtoBinary FormatCapability-Based SecurityCode GenerationIPC5 APIs14.1ASTM InternationalStandardsStandards Development OrganizationConsensus StandardsTechnical Committees2 APIs13.2Component ModelABIBytecode AllianceComponentsInterfaces4 APIs12.7AvoiceCompanyArchitectureEngineeringAECO11.9
Minimal 5 Almost no public developer surface
OpenAPI InitiativeLinux FoundationStandards1 API10.1EditorConfigCoding StandardsConfigurationDeveloper ToolsFile Format9.2Serverless WorkflowAPI CompositionServerless1 API7.5Java EEEnterpriseJakarta EEJavaJava EE4.1Modeling LanguageModeling LanguageSystem DesignUMLSysML3.9

APIs with this tag (75)

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 6 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...82.6Optimizely Specifications APIThe Specifications API from Optimizely — 7 operation(s) for specifications.80.8CarsXE International VIN Decoder APIVIN decoding for non-US vehicles, returning make, model, year, and market-specific trim/spec data for inter...73.9CarsXE Specifications APIVIN decoding for North American and international vehicles — 2 operations (getVehicleSpecs, getInternationa...73.9CarsXE Vehicle Specifications APIVIN decoding and comprehensive vehicle specification lookup. Returns year, make, model, trim, engine, drive...73.9Clerk OpenAPI SpecificationsPublic repository of OpenAPI specifications for Clerk's APIs, used as the source for generated SDKs and doc...71.4
Strong 5 Solid coverage with minor gaps
Aeris Specifications APISpecification Management APIs are for user to get specifications info62.0Autodesk ACC AutoSpecs APIThe ACC AutoSpecs API retrieves Smart Register data from specification PDFs and submittal requirements with...59.9ParlayAPI Specification APIOpenAPI and AsyncAPI specs describing the REST and streaming surfaces.57.8Accruent Specifications APIThe Specifications API from Accruent — 2 operation(s) for specifications.56.0Fusio Specification APIThe specification API from Fusio — 3 operation(s) for specification.55.4
Developing 15 Usable, with meaningful gaps to close
Jentic API AI-Readiness Framework (JAIRF)Technical specification for evaluating how interpretable, operable, and trustworthy an API is for AI system...53.9Buildpack SpecificationThe Buildpack API (currently 0.12) defines the contract between an individual buildpack and the lifecycle. ...53.4Image Extension SpecificationImage extensions emit Dockerfile snippets applied by the `extender` lifecycle binary to the build and/or ru...53.4Platform SpecificationThe Platform API (currently 0.15) defines how platforms (pack, kpack, Tekton Pipelines, GitLab Auto DevOps,...53.4CDEvents SpecificationCDEvents is a common specification for Continuous Delivery events that enables interoperability across CI/C...51.6Cox Automotive Specifications APIThe Specifications API from Cox Automotive — 1 operation(s) for specifications.50.9Buildpack API SpecificationThe Buildpack API is the contract between a buildpack and the lifecycle. It defines the detect and build ex...49.0Distribution API SpecificationThe Distribution API specifies how buildpacks and builders are packaged as OCI artifacts, signed, and distr...49.0Platform API SpecificationThe Platform API is the contract between the CNB lifecycle and a platform such as pack, kpack, or a CI runn...49.0VTEX Specification APIThe Specification API from VTEX — 2 operation(s) for specification.47.13GPP Forge APIThe 3GPP Forge (forge.3gpp.org) is a self-managed GitLab instance where 3GPP publishes the machine-readable...45.8AsyncAPI SpecificationThe AsyncAPI Specification is an open standard for describing asynchronous and event-driven APIs. It provid...45.7API BlueprintAPI Blueprint is a high-level API design language created by Apiary for designing and documenting web APIs....43.9HAProxy Specification APIThe Specification API from HAProxy — 1 operation(s) for specification.43.5Hey API Specifications APIThe Specifications API from Hey API — 1 operation(s) for specifications.42.8
Thin 23 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...38.2Equipmentwatch Specifications APIThe Specifications API from Equipmentwatch — 2 operation(s) for specifications.38.0CloudEvents SpecificationThe CloudEvents specification defines a set of metadata attributes that must be present in every event, inc...37.6CloudEvents SQL (CESQL)CloudEvents SQL (CESQL) is a v1.0 specification that defines a standardized query language for filtering an...37.6OCI Spec for Rustoci-spec-rs is a Rust implementation of the OCI Runtime, Image, and Distribution Specifications, providing ...36.8Kalshi AsyncAPI SpecificationMachine-readable AsyncAPI description of the Kalshi WebSocket streaming API. Suitable for generating async ...35.5Specright APIREST API over Specright's specification data. Forty-six operations across six areas: token issuance, specif...34.2Notary Project Signing SpecificationThe Notary Project specification defines the signature envelope format, trust store and trust policy for co...34.1VINaudit Specifications APIThe Specifications API from VINaudit — 1 operation(s) for specifications.33.7Traceable Specifications APIDownload OpenAPI, WSDL, and other API specification files generated from discovered traffic.33.4THORChain Specification APIThe Specification API from THORChain — 2 operation(s) for specification.31.7Trustworthy Workload Identity (TWI) SpecificationsA working group and set of Internet Draft specifications under the Confidential Computing Consortium that d...31.5API-Fiddle Specifications APIManage API specifications within projects.30.8Apache Arrow Format SpecificationThe Apache Arrow columnar format specification defines the binary layout for in-memory columnar data, inclu...29.4AsyncAPILinux Foundation-hosted specification for event-driven APIs. Describes servers, channels, operations, messa...28.8CloudEventsCNCF-graduated specification (graduated January 25, 2024) for describing event data in a common way. Define...28.8docomo Mail IMAP InterfaceThe docomo Mail IMAP interface is the one machine-interface specification NTT DOCOMO publishes openly, with...28.4APIs.json SpecificationThe APIs.json specification defines a machine-readable JSON or YAML format for describing API operations. U...28.2in-toto Attestation FrameworkThe in-toto Attestation Framework provides a specification for generating verifiable claims about any aspec...27.3in-toto Attestation SpecificationThe in-toto specification defines the metadata format for recording software supply chain steps. It include...27.3MCP SpecificationThe authoritative protocol definition for the Model Context Protocol, maintained at modelcontextprotocol.io...26.7TUF Repository SpecificationThe TUF specification defines the structure of update repositories including the root, targets, snapshot, a...26.6Smithy IDLThe Smithy Interface Definition Language (IDL) is a specification for defining API models using shapes and ...26.5
Emerging 25 Early or largely undocumented
W3C APIThe W3C API provides programmatic access to W3C data including specifications, working groups, editors, tra...26.0W3C Specifications APIThe Specifications API from W3C — 3 operation(s) for specifications.26.0CNI SpecificationThe CNI specification defines the interface between container runtimes and network plugins. It specifies ho...25.4NIST SP 800-207 Zero Trust ArchitectureThe foundational specification of the Zero Trust security model. Defines the seven tenets, the PDP/PEP/PA l...25.4BICS Specification APIThe specification API from BICS — 1 operation(s) for specification.23.3RISC-V ISA SpecificationsThe canonical RISC-V Instruction Set Architecture specifications including the Unprivileged ISA (RV32I/RV64...23.0Jakarta Bean Validation Specification 3.1The Jakarta Bean Validation 3.1 specification defines the constraint model, annotation processor, Validator...22.2Overture SchemaCanonical open schema specification for all Overture themes, maintained in the OvertureMaps/schema GitHub r...19.7TLA+ Community ModulesA curated collection of TLA+ snippets, operators, and modules contributed by the TLA+ community, providing ...19.2TLA+ Specification ExamplesA collection of TLA+ specifications of varying complexity covering distributed algorithms, consensus protoc...19.2JSON:APIJSON:API is a specification for how a client should request that resources be fetched or modified, and how ...17.8OpenAPI SpecificationThe OpenAPI Specification (OAS) defines a standard, language-agnostic interface to RESTful APIs which allow...17.8Apache Parquet Format SpecificationThe core specification for the Parquet columnar storage format.17.3FOCUS (FinOps Open Cost and Usage Specification)FOCUS defines a common normalized data schema for cloud and technology billing data. The specification is d...15.7Cap'n Proto Encoding (Wire Format)The Cap'n Proto encoding specification defines the binary wire format. The in-memory layout is the wire for...14.1Cap'n Proto RPC ProtocolCap'n Proto's RPC protocol is a capability-based RPC layer that supports promise pipelining, object referen...14.1Cap'n Proto Schema LanguageThe Cap'n Proto schema language is used to define message types in .capnp files that are then compiled into...14.1Jakarta JSON BindingJakarta JSON Binding (formerly JSON-B) is a binding framework for converting Java objects to and from JSON ...13.4Jakarta JSON ProcessingJakarta JSON Processing (formerly JSON-P) provides an API to parse, generate, transform, and query JSON doc...13.4Jakarta RESTful Web ServicesJakarta RESTful Web Services (formerly JAX-RS) is the API specification for developing web services that fo...13.4Jakarta ServletJakarta Servlet is a server-side Java API for handling HTTP requests and generating dynamic responses. It p...13.4Jakarta ValidationJakarta Validation (formerly Bean Validation) provides an object-level constraint declaration and validatio...13.4Jakarta WebSocketJakarta WebSocket defines a standard API for creating server and client endpoints that communicate using th...13.4Margo SpecificationMargo defines an open standard specification for interoperability of edge applications, devices, and orches...12.7WebAssembly Component Model SpecificationThe Component Model specification repository under the W3C WebAssembly Community Group. Contains design doc...12.7
Minimal 1 Almost no public developer surface
OpenAPI Initiative APIAPI for accessing OpenAPI Initiative resources, specifications, and tooling ecosystem documentation for def...10.1

Companies reaching this through an API (45)

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 Clerk Cloud Native Buildpacks Confidential Computing Consortium Container Network Interface (CNI) Continuous Delivery Foundation Cox Automotive Equipmentwatch Events Fusio HAProxy In-Toto Jakarta EE Jentic Kalshi Margo Model Context Protocol (MCP) Notary Project NTT Docomo Optimizely Overture Maps Foundation ParlayAPI Redocly REST RISC-V International Smithy Specright The Update Framework (TUF) THORChain Traceable VINaudit VTEX W3C Youki Zero-Trust Security Model

Score breakdown

Frequency
56.8
log-scaled weighted occurrences
Breadth
0.8
spread across providers
Quality lift
32.4
mean composite of providers using it
Cohesion
11.8
strength of nearest seed neighbor

Related tags

Standards 18 co-occurrences Linux Foundation 11 co-occurrences API Design 7 co-occurrences Schema 11 co-occurrences OpenAPI 13 co-occurrences CNCF 6 co-occurrences Go 6 co-occurrences Python 12 co-occurrences

Where this tag comes from

Api tag76
Provider tag32
Openapi tag17
Openapi op tag43

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
of 32 on the roster
Mean Kin Score
26.9
+4.0 vs catalog 22.9
Mean Agent Readiness
15.1
+3.2 vs catalog 11.9
Spread
4.1–79.6
median 20.2 · σ 17.2
How the 29 split by band
Exemplar 1Strong 0Developing 6Thin 6Emerging 12Minimal 4
Facet averages, against the whole catalog
FacetThis cohortCatalogDifferenceScored
Developer Ergonomics 32.5 23.2 +9.3 29
Contract Quality 26.6 17.6 +9 29
Operational Transparency 20.9 13.7 +7.2 29
Contract Governance 11.8 6.3 +5.5 29
Discoverability 59.4 58.1 +1.3 29
Access Clarity 17.6 26.5 -8.9 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% 14% 0
MCP server (first-party) 14% 12% +2
Agent Skills 0% 0% 0
OAuth scopes 7% 11% -4
Security 90% 98% -8
Arazzo workflows 3% 2% +1
Governance rules 38% 14% +24

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 79.6
  2. 2 GSMA 53.8
  3. 3 Buildpacks Io 53.4
  4. 4 AGNTCY 48.4
  5. 5 AsyncAPI 45.7
  6. 6 Hey API 42.8
  7. 7 Craft.io 39.5
  8. 8 Acelab 38.2
  9. 9 CloudEvents 37.6
  10. 10 Alliance for OpenUSD 29.8
Top by Agent Readiness
  1. 1 Postman 54.9
  2. 2 Craft.io 52.9
  3. 3 GSMA 40.8
  4. 4 AGNTCY 39.2
  5. 5 OpenFeature 33.1
  6. 6 Hey API 32.6
  7. 7 Open Geospatial Consortium (OGC) 29.1
  8. 8 Buildpacks Io 28.7
  9. 9 Acelab 25.5
  10. 10 AsyncAPI 25.3
This roster declares 32 members; 30 resolve to a provider in the catalog and 29 carry a score (97%). The figures above describe the scored members only.Generated from the catalog build of 5 October 2026, across 29093 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

curl for this page
This tag 
curl "https://apis.io/api/v1/tags/specification"
All tags 
curl "https://apis.io/api/v1/tags?limit=25"
As a scored cohort 
curl "https://apis.io/api/v1/cohorts/tag/specification"
The distribution (Pro) 
curl "https://apis.io/api/v1/cohorts/tag/specification/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.