swagger-gen
// Generate OpenAPI specs from Express routes. Use when documenting APIs.
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updated:February 19, 2026
SKILL.mdreadonly
SKILL.md Frontmatter
nameswagger-gen
descriptionGenerate OpenAPI specs from Express routes. Use when documenting APIs.
Swagger Generator
Your API has no documentation. This reads your Express routes and generates a complete OpenAPI 3.0 spec.
One command. Zero config. Just works.
Quick Start
npx ai-swagger ./src/routes/
What It Does
- Reads your Express route files
- Generates OpenAPI 3.0 specification
- Documents request/response shapes
- Ready for Swagger UI
Usage Examples
# Generate from routes
npx ai-swagger ./src/routes/
# Single file
npx ai-swagger ./src/routes/users.ts -o docs/api.yaml
Best Practices
- Keep it updated - regenerate when routes change
- Add descriptions - explain what endpoints do
- Include examples - show sample requests
- Document errors - not just happy paths
When to Use This
- Creating API documentation
- Setting up Swagger UI
- Onboarding API consumers
- API-first design
Part of the LXGIC Dev Toolkit
This is one of 110+ free developer tools built by LXGIC Studios. No paywalls, no sign-ups, no API keys on free tiers. Just tools that work.
Find more:
- GitHub: https://github.com/LXGIC-Studios
- Twitter: https://x.com/lxgicstudios
- Substack: https://lxgicstudios.substack.com
- Website: https://lxgic.dev
Requirements
No install needed. Just run with npx. Node.js 18+ recommended. Needs OPENAI_API_KEY environment variable.
npx ai-swagger --help
How It Works
Parses your Express route definitions to extract endpoints, methods, and handler code. Then generates OpenAPI spec with proper types and descriptions.
License
MIT. Free forever. Use it however you want.