Under the hood
An internal MCP connector lookup tool can no longer run in the background
What
An internal tool that resolves MCP (Model Context Protocol, a way of connecting external tools and data sources to Claude) connector payloads by a directory identifier is now marked as never backgroundable. This means it can't be run in a background context, such as inside a subagent (a separate Claude instance spawned to do a sub-task).
Why
Restricting this tool to run only in the main session context suggests it depends on state that isn't reliably available, or safe to use, outside that context.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding does not say what would go wrong if the tool ran in the background, only that it is now disallowed.