Artifact comments and reply actions are present, but their enablement check was not traced to a flag.
What
The artifact tool has new comments and reply actions, with a schema carrying threads and threads_dropped, tool-result text for the empty and degraded cases, and terminal renderers for thread counts and replies.
Details
commentsis read-only and concurrency-safe;replyposts back to a thread- the empty case tells you viewers add threads from the artifact page in comment mode
threads_droppedcovers the degraded case where not every thread came back- gated behind the artifact tool's own isEnabled check, which was not traced to a specific flag, so the live state here is unresolved
Evidence
No comment threads on this artifact yet. Viewers add them from the artifact page (comment mode).
Strings lifted out of the shipped bundle, so the claim above can be checked against them.