# X_DOC_CONFIG_KEY_UNKNOWN

## Means

a page tells a reader to set a key `AppConfig` does not declare

## Typical cause

only `x <command>` citations were resolved, so a `fix:` naming a deleted config key passed every gate — `jobs.driver` was cited four times in `docs/` after 5.0.0 removed it, and two more pages cited `pwa.backgroundSync.retry.maxAttempts` (the field is a boolean) and `realtime.url` (it is `urlEnv`). A phrase-anchored negation filter keeps pages that correctly record a deletion out of the count

## Fix

`name a key AppConfig declares — bun run scripts/config-readers.ts --json lists every leaf`

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