---
'@pdsjs/core': patch
---

A create at a key the repo already holds is refused with 400
`InvalidRequest` ("Record already exists"), as the reference PDS does,
instead of replacing the record. That covers `createRecord` and
`applyWrites#create`, including two creates of one key in one batch, and
a refused batch writes nothing. Clients claim a key by creating at it:
knotless names a repository's record by its name and relies on the create
failing when the name is taken.