Create or replace a memory file

Stores content verbatim at path. No normalisation of any kind: the memory tool’s str_replace is a string operation against exactly these bytes, so re-wrapping or trimming would corrupt the model’s own notes in a way that reads as hallucination. A second write to the same path replaces. userId scopes the file to one end user — two people sharing a workspace key get separate files at the same path, which is deliberate. Source: src/memory-files/memory-file.controller.ts.

Required scope: brain:write.