response-body-content-media-type-changed

Response body contentMediaType changed.

directionresponsearearesponseskindtypeactionchange

Breaking change (level: error)

It changes the type the response returns, so a client expecting the previous type can break.

How to handle this change

When oasdiff flags response-body-content-media-type-changed, you have a few ways to respond:

  • Find a backward-compatible alternative. Redesign the change so clients that followed the old contract keep working, and agree on the approach with whoever introduced it.
  • Release it in a new API version. Keep the current contract and introduce the change in a new version, then deprecate the old one with a sunset date so clients have time to migrate.
  • Accept it as a deliberate breaking change. Sometimes a breaking change is unavoidable, such as an urgent or security fix. Approve it knowingly, document it in your release notes, and tell affected clients. This should be the exception, not a routine way of working.

If oasdiff's verdict does not match your API's compatibility policy, you can also change how it treats response-body-content-media-type-changed with a severity-levels file:

Put one rule per line; the level can be err, warn, or info, or none to disable the check entirely:

# severity.txt
response-body-content-media-type-changed warn

Then pass it to oasdiff:

oasdiff changelog base.yaml revision.yaml --severity-levels severity.txt

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