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DeferredToolPlaceholder: Keeps Deferred Tool Loading Active
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A new placeholder tool named DeferredToolPlaceholder is registered with the description "Reserved placeholder that keeps deferred tool loading active; never call this tool." This internal mechanism ensures the deferred tool loading system remains armed across turn boundaries.
Evidence
Placeholder tool registration (search for "DeferredToolPlaceholder")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.