# X_CLIENT_STALE

## Means

a generated client is older than the document it was compiled from

## Typical cause

the source document (a vendor's source.json, or the app's openapi.json) changed and the client was not regenerated, so it still calls the old contract

## Fix

`x verify --only drift --json` — each finding names the line that regenerates its client

[CLI and verify](/error-codes#cli-and-verify)