Hateoas Agent Skill

> Use when adding hypermedia links to REST responses, building self-describing APIs, or implementing Spring HATEOAS. Use when you see EntityModel, CollectionModel, or RepresentationModel in the project.

3k tokens

context cost

the whole folder, loaded on every use

files

instructions only

copies elsewhere

how many repositories repackaged it

190

stars on the repo

on the repository, not the skill itself

Install

one command, takes just this skill from the repository

npx skills add https://github.com/rrezartprebreza/spring-boot-skills --skill hateoas

The instruction itself

9 sections, as written by the author

Spring HATEOAS

Dependency

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-hateoas</artifactId>
</dependency>

When to Add Links

self — always, on every resource response
collection — link back to the list endpoint
related resources — when a client commonly needs to navigate to them
actions — links to state transitions (e.g., cancel, ship) when valid for current state

Resource Model

public class OrderModel extends RepresentationModel<OrderModel> {
    private final UUID id;
    private final String status;
    private final String customerEmail;
    private final Instant createdAt;

    // Static factory with links
    public static OrderModel from(Order order) {
        OrderModel model = new OrderModel(
            order.getId(), order.getStatus().name(),
            order.getCustomerEmail(), order.getCreatedAt()
        );

        // Self link — always
        model.add(linkTo(methodOn(OrderController.class).getById(order.getId())).withSelfRel());

        // Collection link
        model.add(linkTo(methodOn(OrderController.class).list(null)).withRel("orders"));

        // Conditional action links based on state
        if (order.getStatus() == OrderStatus.PENDING) {
            model.add(linkTo(methodOn(OrderController.class)
                .cancelOrder(order.getId())).withRel("cancel"));
        }
        if (order.getStatus() == OrderStatus.PROCESSING) {
            model.add(linkTo(methodOn(OrderController.class)
                .shipOrder(order.getId())).withRel("ship"));
        }

        return model;
    }
}

Controller

@RestController
@RequestMapping("/api/v1/orders")
public class OrderController {

    @GetMapping("/{id}")
    public ResponseEntity<OrderModel> getById(@PathVariable UUID id) {
        Order order = orderService.findById(id);
        return ResponseEntity.ok(OrderModel.from(order));
    }

    @GetMapping
    public ResponseEntity<CollectionModel<OrderModel>> list(Pageable pageable) {
        Page<Order> orders = orderService.findAll(pageable);

        List<OrderModel> models = orders.getContent().stream()
            .map(OrderModel::from)
            .toList();

        CollectionModel<OrderModel> collection = CollectionModel.of(models,
            linkTo(methodOn(OrderController.class).list(pageable)).withSelfRel()
        );

        // Pagination links
        if (orders.hasNext()) {
            collection.add(linkTo(methodOn(OrderController.class)
                .list(pageable.next())).withRel(IanaLinkRelations.NEXT));
        }
        if (orders.hasPrevious()) {
            collection.add(linkTo(methodOn(OrderController.class)
                .list(pageable.previousOrFirst())).withRel(IanaLinkRelations.PREV));
        }

        return ResponseEntity.ok(collection);
    }
}

Response Shape

{
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "status": "PENDING",
  "customerEmail": "[email protected]",
  "_links": {
    "self": { "href": "http://api.example.com/api/v1/orders/550e8400" },
    "orders": { "href": "http://api.example.com/api/v1/orders" },
    "cancel": { "href": "http://api.example.com/api/v1/orders/550e8400/cancel" }
  }
}

RepresentationModelAssembler Pattern

Spring's recommended way to build HATEOAS models from entities
Implements RepresentationModelAssembler<Entity, Model> — reusable across controllers
Inject the assembler into controllers instead of calling Model.from() directly

@Component
public class OrderModelAssembler implements RepresentationModelAssembler<Order, EntityModel<OrderResponse>> {

    @Override
    public EntityModel<OrderResponse> toModel(Order order) {
        EntityModel<OrderResponse> model = EntityModel.of(OrderResponse.from(order),
            linkTo(methodOn(OrderController.class).getById(order.getId())).withSelfRel(),
            linkTo(methodOn(OrderController.class).list(null)).withRel("orders"));

        if (order.getStatus() == OrderStatus.PENDING) {
            model.add(linkTo(methodOn(OrderController.class)
                .cancelOrder(order.getId())).withRel("cancel"));
        }
        return model;
    }
}

PagedModel for Paginated Collections

Use PagedResourcesAssembler for automatic pagination links (first, prev, next, last)
Inject PagedResourcesAssembler<Order> into controllers — Spring creates it automatically

@GetMapping
public ResponseEntity<PagedModel<EntityModel<OrderResponse>>> list(
        Pageable pageable, PagedResourcesAssembler<Order> pagedAssembler) {
    Page<Order> orders = orderService.findAll(pageable);
    PagedModel<EntityModel<OrderResponse>> pagedModel =
        pagedAssembler.toModel(orders, orderModelAssembler);
    return ResponseEntity.ok(pagedModel);
}

Gotchas

Agent adds all links regardless of state — only add action links when the action is valid
Agent hardcodes URLs in links — always use linkTo(methodOn(...)) for type-safe links
Agent returns plain DTO — wrap in EntityModel.of(dto, links...) or extend RepresentationModel
Agent puts link logic in controller — extract to RepresentationModelAssembler
Agent manually builds pagination links — use PagedResourcesAssembler instead
Agent forgets self link — every resource must have a self link

Other skills for the same job

different authors, same section of the catalogue

MCP Builder

by anthropics

vendor ×13

Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).

Automatically creates user-facing changelogs from git commits by analyzing commit history, categorizing changes, and transforming technical commits into clear, customer-friendly release notes. Turns hours of manual changelog writing into minutes of automated generation.

774 tokens

Finishing A Development Branch

by ZhanlinCui

×7

Use when implementation is complete, all tests pass, and you need to decide how to integrate the work - guides completion of development work by presenting structured options for merge, PR, or cleanup

Vercel React Native Skills

by vercel-labs

vendor ×6

React Native and Expo best practices for building performant mobile apps. Use when building React Native components, optimizing list performance, implementing animations, or working with native modules. Triggers on tasks involving React Native, Expo, mobile performance, or native platform APIs.

39k tokens

Vercel React Best Practices

by ratacat

×5

React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance improvements.

Next.js best practices - file conventions, RSC boundaries, data patterns, async APIs, metadata, error handling, route handlers, image/font optimization, bundling

Use when starting feature work that needs isolation from current workspace or before executing implementation plans - creates isolated git worktrees with smart directory selection and safety verification

1k tokens

How to use it

Copy the folder

Take rrezartprebreza/hateoas from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.