How to use OpenAPI Breaking-Change Studio

Compare OpenAPI JSON or YAML and surface removed endpoints, operations, responses, schemas, and newly required parameters.

1. Paste, type, or drag and drop a supported text file into the input area.
2. Place the second value or file in the adjacent panel. Sensitive fields are masked by default.
3. Review the input and the clearly labeled output behavior.
4. Select “Run tool” or press Ctrl/Command + Enter, then copy, download, or move the result back into the first input for another pass.

Use “Swap inputs” to reverse the comparison without copying either value.

What the result means

A compatibility report with breaking and additive changes linked to contract paths.

Privacy and safety

This utility is loaded as browser code and processes your input only in this tab. OmniCastConverter has no upload endpoint and never stores your content, filenames, tokens, or secrets. Generated markup and code are shown as inert text and are never executed.

Limitations

• Everything is processed in this browser tab. Input, filenames, keys, and output are never uploaded or saved. Consumer-specific semantics, discriminator behavior, custom formats, examples, and runtime compatibility still require contract tests.

Try the included example

Select “Load example” at any time to restore this tested sample.

openapi: 3.1.0
info: {title: Local API, version: 1.0.0}
paths:
  /users:
    get:
      responses:
        "200": {description: OK}

openapi: 3.1.0
info: {title: Local API, version: 2.0.0}
paths: {}