{"name":"tengu_deferred_stub_tool","slug":"tengu-deferred-stub-tool","family":"flag","title":"Feature flags","noun":"feature flag","description":"Default `true`, read once per session and then kept. When on and deferred tool loading is in use, a request's tool list gains a tool named `DeferredToolPlaceholder` with `defer_loading` set, described as `Reserved placeholder that keeps deferred tool loading active; never call this tool.`, unless one is already there. It is never added under HIPAA restrictions, or while `CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS` is set and tool search is not forced on.","description_source":"code","described_by":{"bundle":"2.1.286","author":"claude-opus-5-5"},"presence":{"first_seen":"2.1.207","removed_in":null,"in_current_build":true,"newest_mined":"2.1.308","builds":90,"mined_builds":149,"first_cited":null},"aliases":[],"entries":[],"entries_total":0,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"tengu_deferred_tools_pool_change","slug":"tengu-deferred-tools-pool-change","description":"Deferred-tool telemetry now tracks resurfaced tools and whether tool search is unavailable"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/flag\/tengu-deferred-stub-tool","family_url":"https:\/\/changelogs.core-directive.com\/reference\/flag.json"}