OhAPI

OhAPI is a native macOS app for developers and API architects who work with OpenAPI specifications. It makes complex definitions easier to understand through an interactive tree visualization, a powerful code viewer, and a dedicated operations browser. Interactive Tree Visualization Turn your specification into a clear, structured graph: schemas, properties, parameters, references, and compositions (allOf, anyOf, oneOf) become visual nodes with color cues. • Expand/collapse sections to stay focused • Select a node to automatically highlight the corresponding source • Jump through $ref references instantly • Smooth animations for easier reading JSON/YAML Viewer with Syntax Highlighting Read the raw spec with a view optimized for clarity: • JSON and YAML syntax highlighting • Line numbers • Two-way sync between “tree ↔ source” (auto-scroll to the relevant line) Operations Browser Browse your API by endpoints and HTTP methods: • Operations list (GET, POST, PUT, DELETE, etc.) • Details (summary, operationId, description) • Requests and responses grouped by HTTP status (2xx, 4xx/5xx, default) Reference Resolution with Cycle Detection OhAPI resolves references across the spec (OpenAPI 3.x and Swagger 2.0) and safely handles circular references to avoid infinite recursion. Native macOS, Document-Based Workflow OhAPI behaves like a true macOS app: • Open via File > Open, drag & drop, or Finder double-click • Multiple documents in separate windows • Recent files support • Built-in examples to get started quickly Formats & Compatibility • File formats: .json, .yaml, .yml • Versions: Swagger 2.0, OpenAPI 3.0.x, OpenAPI 3.1.x • Light/Dark Mode and customizable node colors Built with Swift and AppKit, OhAPI is designed to be fast, stable, and deeply integrated into macOS.