An index and topic collection covering hypermedia-driven APIs, HATEOAS, and the formats, link relations, and specifications that make APIs discoverable and self-describing. Hypermedia APIs use links, link relations, and embedded controls inside their responses so that clients can navigate an API graph at runtime rather than relying on hard-coded URI structures. This collection covers hypermedia formats including HAL, JSON:API, Siren, Collection+JSON, JSON-LD, Hydra, ALPS, UBER, Mason, and Verbose; the standards bodies that define web linking (IETF, W3C) including RFC 5988/8288 Web Linking and RFC 9264 api-catalog; provider APIs that demonstrably ship HATEOAS responses; and the spec libraries and frameworks that implement hypermedia patterns.
URL: https://apievangelist.com
Run: Capabilities Using Naftiko
- Hypermedia, HATEOAS, HAL, JSON:API, Link Headers, Link Relations, Siren, Collection+JSON, Linked Data, JSON-LD, Hydra, ALPS
- Created: 2026-05-19
- Modified: 2026-05-19
- Portal
- GitHubOrganization
- JSONSchema - HAL Resource Schema
- JSONSchema - Link Relation Schema
- JSON-LD
- Vocabulary
| Name | Description |
|---|---|
| HATEOAS Navigation | Hypermedia APIs include in-response links and link relations so clients can discover available state transitions at runtime rather than hard-coding URI templates against documentation. |
| Standardized Hypermedia Formats | Established formats such as HAL, JSON:API, Siren, Collection+JSON, Hydra, ALPS, UBER, Mason, and Verbose provide structured ways to embed links, actions, and metadata inside API responses. |
| Web Linking via Link Headers | RFC 5988 and RFC 8288 define the HTTP Link header and the Web Linking model, including the IANA Link Relations registry that gives shared meaning to rel values across APIs. |
| Linked Data and Semantic Hypermedia | JSON-LD, Hydra, schema.org, and the broader RDF stack extend hypermedia with shared vocabularies, enabling semantic interoperability between APIs, search engines, and knowledge graphs. |
| Self-Describing API Catalogs | RFC 9264 api-catalog, APIs.json, and similar discovery documents act as hypermedia entry points that link a host to its APIs, OpenAPI specs, terms of service, and policies. |
| Hypermedia Frameworks and Libraries | Frameworks like Spring HATEOAS, Spring Data REST, and Apicurio provide implementation support for emitting HAL, HAL-FORMS, JSON:API, and Collection+JSON responses from server code. |
| Name | Description |
|---|---|
| Evolvable Long-Lived APIs | HATEOAS-based APIs allow servers to evolve URI structures and add new affordances while clients continue to navigate by link relations rather than hard-coded paths. |
| Domain-Driven Project Management APIs | OpenProject exposes work packages, projects, users, and attachments through a HAL+JSON hypermedia API where every resource embeds links to related resources and available actions. |
| Standardized CRUD via JSON:API | Patreon, MBTA, Teamtailor, and Drupal expose their resources via JSON:API, providing a consistent specification for fetching, including related resources, filtering, sorting, and pagination. |
| Semantic Search and Structured Data | Schema.org and JSON-LD allow APIs and websites to publish machine-readable Linked Data that search engines, agents, and aggregators can consume without bespoke parsers. |
| API Discovery and Catalogs | APIs.json and RFC 9264 api-catalog documents act as hypermedia entry points that let crawlers, tooling, and AI agents discover an organization's APIs, specifications, and policies. |
| Hypermedia-Driven Web Apps | Approaches like htmx, hyperview, and Hypermedia Systems return HTML fragments and hypermedia controls directly to the client, treating HTML itself as the hypermedia format. |
| Name | Description |
|---|---|
| HAL (Hypertext Application Language) | A minimal hypermedia format for JSON and XML that embeds _links and _embedded resources, widely used by APIs such as OpenProject, Reverb, and Spring Data REST. |
| JSON:API | A specification for building APIs in JSON that standardizes resource objects, relationships, includes, filtering, sorting, and pagination, used by Patreon, MBTA, Teamtailor, and Drupal. |
| Siren | A hypermedia specification for representing entities, their classes, properties, actions, and links, designed for rich, action-oriented hypermedia clients. |
| Collection+JSON | A JSON-based hypermedia format from Mike Amundsen for representing collections of items with queries and templates for write operations. |
| JSON-LD and Hydra | JSON-LD provides a JSON syntax for Linked Data; Hydra extends it with a vocabulary for describing hypermedia-driven Web APIs including operations, classes, and supported properties. |
| ALPS (Application-Level Profile Semantics) | A profile description format for documenting semantic descriptors and state transitions independent of any single media type. |
| Web Linking (RFC 5988 / RFC 8288) | IETF specifications defining the HTTP Link header and a model for typed web links, along with the IANA Link Relations registry shared across hypermedia formats. |
| Spring HATEOAS | A library for building hypermedia-driven REST APIs in Spring, supporting HAL, HAL-FORMS, Collection+JSON, and UBER, with first-class integration into Spring Data REST. |
Machine-readable API specifications organized by format.
- Hypermedia Vocabulary — Unified taxonomy mapping hypermedia formats, link relations, resources, actions, workflows, and personas across HATEOAS APIs and hypermedia frameworks
This index references the following hypermedia, HATEOAS, and link-relation repositories:
- Apicurio
- APIs.json
- Design Patterns
- Drupal
- MBTA
- OpenProject
- Patreon
- RDF
- REST
- RESTful
- RESTful APIs
- RESTful Services
- Reverb
- Schema.org
- SPARQL
- Spring Boot
- Spring Boot 3
- Spring Data
- Spring Framework
- Teamtailor
- Technology Standards
- W3C
- Web Standards
- Wikidata
FN: Kin Lane
Email: kin@apievangelist.com