You'll notice
Useful2 Signal3
Sync no longer asks which mode to use when the repo might be the Anthropic monorepo.
What's wrong with this entry?
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What
Claude Code reads the repository's git config and remotes to decide whether a directory could be the Anthropic monorepo. If it cannot rule that out, or the config cannot be read at all, the sync-mode prompt is skipped and recorded with the reason monorepo_or_unreadable_config. The same check drives which memory guideline paths cowork uses. This runs unconditionally, with no flag.
Evidence
monorepo_or_unreadable_config
Strings lifted out of the shipped bundle, so the claim above can be checked against them.