Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
SubagentsArea: what it touches
Internal ChangesKind: in v2.1.296,
Internal ChangesSection of the release
Unclear Whether any tool actually behaves differently for subagents or by session version yet is not shown.
What
A tool call is a request from Claude to use one of its tools, such as reading a file or running a command. On one of the paths Claude Code uses to run tool calls, it now gives the tool two more pieces of information:
sessionVersion: the version of the session the call is running in
isSubagent: whether the call came from a subagent, which is a helper agent Claude starts to handle part of a task
Before, the tool got neither of these.
Why
Tools on this path now have what they need to act differently for subagents, or for different session versions.
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtWhether any tool actually behaves differently for subagents or by session version yet is not shown.
