RunLogosPhase 04 · API Design
The API Skill reads your sequence diagrams and generates a complete OpenAPI 3.0 specification. Every endpoint traces back to a specific step in a scenario diagram — nothing is invented.
What it produces
logos/resources/api/openapi.yaml — a full OpenAPI 3.0 spec with:
- All paths and HTTP methods
- Request body schemas
- Response schemas with status codes
- Authentication requirements per endpoint
- Error response definitions
Traceability
Each endpoint in the spec includes a comment referencing its scenario step:
/auth/register:
post:
summary: Register a new user
# Scenario: S01 step 2 — App → API
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/RegisterRequest'
Viewing the spec
RunLogos renders the OpenAPI YAML in the built-in API viewer — browse endpoints, see schemas, and verify against the sequence diagrams side-by-side.