{"version":"2.1.223","anchor":"thrifty-sonic-narrowed-to-one-model-plan-artifacts-moved-to-","canonical_anchor":"thrifty-sonic-narrowed-to-one-model-plan-artifacts-moved-to-","heading":"Thrifty-sonic narrowed to one model; plan artifacts moved to its own gate","tier":"soon","area":"Plan Mode","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.223\/e\/thrifty-sonic-narrowed-to-one-model-plan-artifacts-moved-to-","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.223","markdown":"### Thrifty-sonic narrowed to one model; plan artifacts moved to its own gate\n\nPlan artifacts now have their own switch instead of riding along with an unrelated experiment.\n\n**What**\n\nThe thrifty-sonic experiment now only applies to a single model, and the plan-artifacts toggle no longer shares its gate.\n\n**Details**\n\n- The thrifty-sonic check short-circuits unless the model resolves to `claude-opus-5`, before `tengu_thrifty_sonic` is consulted; its environment variable is unchanged.\n- Plan artifacts now read the environment variable `CLAUDE_CODE_PLAN_ARTIFACTS` and the gate `tengu_basalt_loom`, which falls back to false, replacing the `tengu_thrifty_sonic` read that was there.\n\n**Evidence**\n\n`CLAUDE_CODE_PLAN_ARTIFACTS`\n\n- Flag `tengu_thrifty_sonic`: Off by default, switched on for this account (read for one account on one subscription tier against v2.1.223; this account: on, anonymous baseline: on, compiled default: off) 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.\n- Flag `tengu_basalt_loom`: Not enough to say (read for one account on one subscription tier against v2.1.223; this account: no value returned, anonymous baseline: no value returned, compiled default: off) 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.\n- Area: Plan Mode\n- Names: `CLAUDE_CODE_PLAN_ARTIFACTS`\n- Tier: Nothing to try yet\n- Useful: 3\/5\n- Signal: 4\/5\n- Present in the build but not switched on"}