Under the hood
Artifact source-content markers are now generated deterministically instead of randomly
What
When the composer needs to embed an artifact's current source code in its prompt so it can be edited, it fences that content with a unique marker (a 'nonce') to distinguish it from other text. That marker is now computed deterministically from a hash of the artifact's slug, version, and content, rather than being a fresh random value that got regenerated whenever it happened to collide with existing text.
Why
A deterministic marker means the same artifact version always gets the same fence, making it easier to detect stale or replayed source content reliably instead of relying on random collision avoidance.