# OpenAPI Generator

> OpenAPI Generator is a community-governed, Apache-2.0 open-source project that generates client libraries (SDKs), server stubs, API documentation and configuration from an OpenAPI Specification (v2 and v3). It is a fork of Swagger Codegen created in 2018 by more than 40 of that project's top contributors and template creators, and is one of the most widely deployed implementations of the OpenAPI Specification in existence. The primary product is a CLI and a set of build-tool plugins; a hosted REST API at api.openapi-generator.tech offers the same generation over HTTP.

Generated by the API Evangelist enrichment pipeline on 2026-08-06 from https://openapi-generator.tech and the project's own published artifacts. The project does not publish an llms.txt of its own (https://openapi-generator.tech/llms.txt returned 404 on 2026-08-06).

## Two surfaces, and the difference matters

- **The CLI and plugins** are the supported product. Install via npm, Homebrew, Scoop, PyPI, Docker, a JAR, or JBang; run `generate`, `validate`, `list`, `config-help`, `batch`, `author`, `meta`, `version`. Requires Java 11+. Current release 7.24.0 (2026-07-20).
- **The hosted Online Generator API** (https://api.openapi-generator.tech) is a five-path, seven-operation REST service with no authentication, no rate-limit signalling, no idempotency and no status page. Its deployed build reports version 7.12.0, twelve minor versions behind the current release line. Use it for convenience and experiments; use the CLI for anything you depend on.

## Docs

- [Getting Started / CLI Installation](https://openapi-generator.tech/docs/installation): every install channel with the exact command for each platform.
- [Usage](https://openapi-generator.tech/docs/usage): the full CLI command surface with options, presented as a tutorial.
- [Generators](https://openapi-generator.tech/docs/generators): every available generator and its stability index (stable, beta, experimental, deprecated).
- [Plugins](https://openapi-generator.tech/docs/plugins): Maven, Gradle and sbt build-time generation.
- [Online](https://openapi-generator.tech/docs/online): the hosted generation API.
- [Roadmap](https://openapi-generator.tech/docs/roadmap): short-, medium- and long-term goals, explicitly framed as goals not commitments.
- [FAQ](https://openapi-generator.tech/docs/faq): governance, the Swagger Codegen relationship, chat room.
- [Contributing](https://openapi-generator.tech/docs/contributing)
- [Team](https://openapi-generator.tech/team)
- [Blog](https://openapi-generator.tech/blog)

## API

- [Online Generator API reference](https://api.openapi-generator.tech/): RapiDoc rendering of the live contract.
- [Swagger 2.0 contract](https://api.openapi-generator.tech/api-docs): the machine-readable document, saved in this repo at `openapi/openapi-generator-online-swagger.json`.

Operations:

- `GET /api/gen/clients` (`clientOptions`) — list client generators (84 at last probe).
- `GET /api/gen/clients/{language}` (`getClientOptions`) — config options for one client generator.
- `POST /api/gen/clients/{language}` (`generateClient`) — generate a client; returns a download `code`.
- `GET /api/gen/servers` (`serverOptions`) — list server generators (65 at last probe).
- `GET /api/gen/servers/{framework}` (`getServerOptions`) — config options for one server framework.
- `POST /api/gen/servers/{framework}` (`generateServerForLanguage`) — generate a server stub; returns a download `code`.
- `GET /api/gen/download/{fileId}` (`downloadFile`) — download a generated artifact by its code.

Runtime semantics: no auth, no pagination, no idempotency, no request-id header, unversioned paths, Spring Boot default error envelope (`{timestamp,status,error,path}`) rather than RFC 9457. An unknown download code returns 500, not 404.

## Packages

- npm: `@openapitools/openapi-generator-cli` (`npm install @openapitools/openapi-generator-cli -g`)
- PyPI: `openapi-generator-cli` (`pip install openapi-generator-cli`)
- Maven Central: `org.openapitools:openapi-generator-cli`, `:openapi-generator`, `:openapi-generator-core`, `:openapi-generator-maven-plugin`, `:openapi-generator-gradle-plugin`, `:sbt-openapi-generator`, `:openapi-generator-online`, `:jackson-databind-nullable`
- Docker Hub: `openapitools/openapi-generator-cli`
- Homebrew: `brew install openapi-generator` · Scoop: `scoop install openapi-generator-cli`

## Source and community

- [GitHub organization](https://github.com/OpenAPITools)
- [Main repository](https://github.com/OpenAPITools/openapi-generator) — Apache-2.0, ~26.6k stars.
- [Releases / change log](https://github.com/OpenAPITools/openapi-generator/releases) — semver, a minor release roughly every 4–8 weeks.
- [Issues](https://github.com/OpenAPITools/openapi-generator/issues) · [Stack Overflow](https://stackoverflow.com/questions/tagged/openapi-generator)

## Optional

- No `/.well-known/security.txt`, `openid-configuration`, `oauth-authorization-server`, `api-catalog`, `ai-plugin.json`, agent card or `llms.txt` is served on either host — all returned 404 on 2026-08-06.
- No official MCP server is published. A candidate tool mapping over the seven REST operations is recorded in this repo at `mcp/openapi-generator-mcp.yml` and is not a project product.
- No commercial plans, SLA, status page, security disclosure policy, bug bounty, trust center or compliance certification is published. This is a volunteer-governed open-source project and free to use.