New plugin hook lets a plugin check whether a tool call would be allowed without actually running it
Plugins (add-on scripts that can hook into Claude Code's behavior) can now call a new $.tool.check operation. Given a tool name and its input, this runs the same permission and argument checks Claude Code would normally run before executing that tool, and returns the verdict (allowed, denied, etc.) without actually running the tool. It's also wired into the tool-call hook used by the Claude Code SDK, which now validates the tool name and input before dispatching to this new check.
This lets a plugin or SDK integration preview whether a tool call would be permitted, useful for building custom approval flows or diagnostics without side effects from actually running the tool.