Tool search is how Claude finds and loads tools that are held back until needed. After a search, Claude Code can now measure the size of each matched tool's definition and leave some out:
- tools that are already loaded
- tools too large for the context window on their own (the context window is the amount of text Claude can hold at once)
- tools that would go over the room still left
When tools are left out, Claude receives a note saying why. This size check is off unless it is switched on remotely with a fraction of the context to use.
It stops a search from pulling in very large tool definitions, such as big MCP tool descriptions, that would overflow what Claude can hold.
tengu_measured_shelf Not enough to sayNothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.
This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.318: not a boolean we can read
These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.
Read once, for one account on one subscription tier, against v2.1.318. It isn't a statement about your account. What a flag value here can and cannot tell you
New in this build: tengu_measured_shelf