Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.302,
Internal ChangesSection of the release
What
MCP servers are outside programs that give Claude Code extra tools. Claude Code already attached timing details to MCP tool responses, such as start time, uptime and CPU time.
It now also reads the file cpuacct.usage from the cgroup. A cgroup is a Linux feature that groups processes and tracks the resources they use. When the reading looks sane, Claude Code adds shell_cpu_ms, the CPU time used by the shell in milliseconds, to those details.
Why
Hosted environments get a measure of how much CPU the shell used, next to the timing figures that were already reported.
