REST API Contract Designer
Design clear REST API contracts with resources, endpoints, schemas, validation, errors, pagination, versioning, security, and examples.
REST API Contract Designer is a free AI skill for api & integration building. Design clear REST API contracts with resources, endpoints, schemas, validation, errors, pagination, versioning, security, and examples. It works with Claude, ChatGPT, Cursor and is ready to use out of the box.
About this skill
REST API Contract Designer turns a product requirement or integration need into a developer-ready REST API specification. It defines resources, endpoint semantics, request and response schemas, validation rules, status codes, errors, authentication, pagination, filtering, idempotency, versioning, observability, and acceptance tests.
What it does
The skill analyzes the business workflow and data model, identifies API consumers and systems of record, defines resource boundaries and endpoint behavior, creates structured schemas and error contracts, adds security and reliability requirements, and produces an implementation-ready specification suitable for OpenAPI, backend development, frontend integration, and QA.
What is included
- Resource and endpoint model
- Request and response schemas
- Validation rules
- Error contract
- Authentication and authorization requirements
- Pagination and filtering rules
- Versioning and idempotency guidance
- Acceptance test scenarios
How to use it
1. Download the rest-api-contract-designer-SKILL.md file 2. Upload it to your AI or development workspace 3. Describe the product workflow, consumers, and data entities 4. Add technical constraints and existing API conventions 5. Use the final contract for implementation, review, and testing
Examples
Design a REST API for a SaaS application where users upload CSV files, start an analysis job, view job status, retrieve results, and delete their data.
A complete API contract with resources, endpoint table, request and response schemas, validation, upload and job-state rules, error model, authentication, authorization, pagination, idempotency, rate-limit guidance, and acceptance tests.
FAQ
What is this skill for?
Can it generate OpenAPI?
Does it decide the database schema?
How does it handle errors?
Can it design secure endpoints?
How is this different from listing endpoints?
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