OhAPI Designer for Mac

OhAPI Designer is a document-based macOS application built specifically for authoring and editing OpenAPI (formerly Swagger) specification files. It combines the speed of a native text editor with deep OpenAPI awareness — context-sensitive completions, inline validation, structured navigation, and a visual operations panel — all in a single window.

Supports OpenAPI 3.0 and 3.1 in both JSON and YAML formats.

Intelligent Code Editor

• Syntax highlighting for JSON and YAML with viewport-first rendering — the visible code is highlighted instantly, even in large files
• Line numbers, indent guides, and current line highlight for easy orientation
• Auto-indentation — language-aware rules for both JSON and YAML
• Breadcrumb navigation — see your cursor's structural position in the document (e.g., paths › /users › get › responses › 200) and click any segment to jump there
• Dark and light mode — adapts automatically to macOS system appearance

Context-Aware Auto-Completion

Press Ctrl+Space to trigger completions. OhAPI Designer analyzes your cursor position within the OpenAPI schema and suggests valid keys, values, and references. Existing keys are filtered out, so only what's missing is suggested.

Snippet Templates

• Type a trigger keyword and a ghost text preview appears inline — press Tab to accept
• Tab through placeholders to fill in each field, Xcode-style
• 20+ built-in templates covering common OpenAPI structures (operations, schemas, parameters, responses, security schemes, and more)
• Templates adapt to the document format (JSON/YAML) and OpenAPI version (3.0/3.1)
• Add your own custom templates

Clickable $ref Navigation

Cmd+Click any $ref reference to jump directly to its definition. References are styled as blue underlined links for instant recognition.

OpenAPI Validation

• Red wavy underlines for errors, amber for warnings — directly in the editor
• Hover tooltips display the error message and source location
• Full validation against the OpenAPI 3.0 and 3.1 specifications, including $ref resolution

Operations Panel

• Operations table — all endpoints listed with color-coded HTTP method badges, paths, and summaries
• Tabbed detail view — Description, Body (parameters, request body, responses), Schema Explorer (interactive tree with Referenced/Resolved modes), and Example Viewer
• Example generation — realistic JSON examples generated from your schemas when none are defined
• Click to navigate — jump from any element in the panel to its source location in the editor
• Live updates — the panel refreshes automatically as you type

More Features

• JSON ↔ YAML conversion — switch formats with one click in the toolbar
• New document wizard — choose OpenAPI version, format, and initial paths
• External file change detection — automatic reload or conflict dialog
• Console — color-coded event log with clickable entries
• Customizable preferences — editor behavior, indentation, and syntax colors for dark and light mode
• Built-in user manual

Built for macOS

OhAPI Designer is a native Swift/AppKit application — no Electron, no web views for the editor. It supports multiple documents in tabs, autosave, and runs in a secure App Sandbox. Available for Apple Silicon and Intel Macs.