Compare specs

A dedicated page (linked from the sidebar as "Compare specs") that fetches two OpenAPI documents by URL and reports what changed between them: added, removed, and changed endpoints, each flagged breaking or informational.

Usage

Click Compare specs in the sidebar, paste a URL for the base (old) spec and one for the new spec (the new field is prefilled with whichever spec is currently loaded), then click Compare. Both documents go through the exact same normalizeDocument() pipeline the main viewer uses, so there's no separate parser to trust.

What counts as breaking

ChangeSeverity
Endpoint removedBreaking
New required parameterBreaking
Optional parameter became requiredBreaking
Request body became requiredBreaking
A 2xx response was removedBreaking
Endpoint addedInformational
Parameter removedInformational
A non-2xx response was removedInformational
New response status documentedInformational

Scope

This is deliberately shallow: it compares endpoint presence, parameter presence/ required-ness, request body required-ness, and response status codes. It does not diff schema shapes field-by-field (e.g. a property quietly changing from string to number is not caught yet).