# X_PROBLEM_META_INVALID

## Means

a problem document cannot carry that meta declaration

## Typical cause

`registerProblemMeta()` given a framework-owned code (its `meta` is operator-only — the body excerpt `bodyInvalid` keeps there, the limiter's key), a key that is not one (`issues` already rides at the document's top level; `__proto__`), an empty list, or a second, different list for one code

## Fix

`registerProblemMeta({ X_YOUR_CODE: ['sessionId'] })` with the keys your own error puts in `meta`, beside its `registerErrorStatus()` call — both are needed, because a code with no status is an unclassified 5xx whose `meta` is blanked with its `cause`

[HTTP](/error-codes#http)