What Contract Registry does
Record contract versions on this device and see how a payload's shape has drifted over time.
Also searched as registry, contract history, versions, drift over time, schema history, api versions, changelog.
Infer and store the payload's shape
Skip a recording when nothing changed
Classify drift between consecutive versions
Shapes are stored, payloads are not
Each entry keeps the inferred schema, never the document. History stays useful and nothing sensitive is written to storage.
This device only
The registry lives in local storage. There is no account, no sync, and no server copy — clearing site data clears the history.
Contract Registry FAQ
Does jsontools.me upload my JSON?
No. The document is parsed and processed by json-buf inside a dedicated WebAssembly worker on your device.
Does it work offline?
Yes. After the application shell and engine have loaded once, the installable PWA keeps the tools available without a network connection.