Why: The composed reply copied the registered artifact id and file size out of the tool summary.
Evidence: go test ./internal/runtime/ -run 'TestComposeUserPromptOmitsArtifactIDs|TestComposeReplyDropsInternalRefs'
Impact: Those tokens are removed from the compose input and from the reply before it is shown.
Refs: feature/final-reply-compose
Co-authored-by: Cursor <cursoragent@cursor.com>