OpenAPI Converter

Convert OpenAPI and Swagger files, or move supported description markers into OpenAPI fields, directly in VS Code.

No telemetry. No network requests. The extension does not store your files.

Commands

Command	What it does
OpenAPI: Convert Version	Converts between Swagger 2.0 and OpenAPI 3.0, 3.1, or 3.2. Input and output can be JSON or YAML.
OpenAPI: Apply Markers	Turns supported `[field: value]` markers in descriptions into OpenAPI fields.

Convert a file

From / to	Swagger 2.0	OpenAPI 3.0	OpenAPI 3.1	OpenAPI 3.2
Swagger 2.0	JSON ↔ YAML	Convert	Convert	Convert
OpenAPI 3.0	Convert*	JSON ↔ YAML	Convert	Convert
OpenAPI 3.1	Convert*	Convert*	JSON ↔ YAML	Convert
OpenAPI 3.2	Convert*	Convert*	Convert*	JSON ↔ YAML

All conversions support JSON and YAML input and output.

* The target version is older and may not support every feature. The extension completes the conversion and lists anything adjusted or removed. Your source file stays unchanged, and you decide whether to save the result.

To convert a file:

Open a JSON or YAML file, or right-click it in the Explorer.
Run OpenAPI: Convert Version.
Choose the target version and output format.
Review the result in a new tab. Select Save As to save it.

Apply markers

A supported marker in a description becomes an OpenAPI field. The marker is then removed from the description.

Customer request number. [example: "RQ/2026/000123"] [pattern: "^RQ/\d{4}/\d{6}$"]

becomes:

requestNumber:
  type: string
  description: Customer request number.
  pattern: ^RQ/\d{4}/\d{6}$
  example: RQ/2026/000123

Unsupported markers, such as [TODO: ...], remain unchanged. Invalid values are not applied. Running the command again does not change an already processed file.

OpenAPI: Convert Version applies supported markers before converting the file. See the marker reference for all supported markers and value rules. A complete example is available in examples/markers-swagger2.json.

Privacy and security

All processing happens on your computer. The extension makes no network requests, sends no telemetry, and does not download external $ref files. It stores nothing: a result is written only when you save it. Restricted Mode is supported. The security policy describes the full scope.

Installation

Install OpenAPI Converter from the Visual Studio Code Marketplace, or download a .vsix file from the GitHub releases page and run Extensions: Install from VSIX.

Support

Report bugs in GitHub Issues. For security issues, and for what must not go into a report, read the security policy.

MIT License · Changelog

OpenAPI Converter

Beata Humeniuk

OpenAPI Converter

Commands

Convert a file

Apply markers

Privacy and security

Installation

Support