Generate OpenAPI 3.0 documentation from Java source without annotations or a running app. OneAPI.app analyzes your code via AST — zero intrusion, zero setup. No @Operation, no Spring Boot startup required.
Drop-in replacement for Swagger and springdoc-openapi. You don't touch a line of business code and add zero annotations. Point OneAPI at your project and get docs.
Docs are derived directly from your Java source and Javadoc. What compiles is what gets documented — no drift, no separate spec to maintain.
The same oneapi.json schema drives both backend OpenAPI output and frontend service code (TypeScript). Pipe it into UmiJS, Postman, or your own tooling.
oneapi analysis parses your Java project (and decompiles JARs for third-party types) into oneapi.json.
oneapi analysis -p <project> -o <dir>oneapi openapi emits an OpenAPI 3.0 file you can import anywhere.
oneapi openapi -s oneapi.json -o <dir>oneapi service produces typed TypeScript service functions from the same schema.
oneapi service -s oneapi.json -r '<request import>' -o <dir>Install the CLI and point it at any Spring Boot project — no annotations required.
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