{"version":"2.1.68","anchor":"ultrathink-keyword-re-enabled-as-effort-boost","canonical_anchor":"ultrathink-keyword-re-enabled-as-effort-boost","heading":"Ultrathink keyword re-enabled as effort boost","tier":null,"area":null,"scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.68\/e\/ultrathink-keyword-re-enabled-as-effort-boost","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.68","markdown":"### Ultrathink keyword re-enabled as effort boost\n\n**What**\n\nTyping \"ultrathink\" in a message now sets reasoning effort to \"high\" for that turn. In the previous version, ultrathink was deprecated and showed a dismissive message \u2014 it now has real functionality again.\n\n**Usage**\n\n`ultrathink about the architecture of this codebase and suggest improvements` **Details** - When \"ultrathink\" appears anywhere in your message, effort is automatically set to high for that turn - A notification briefly displays: \"Effort set to high for this turn\" - The word \"ultrathink\" is rendered with a rainbow color shimmer effect in the terminal (cycling through red, orange, yellow, green, blue, indigo, and violet) - Controlled by the `tengu_turtle_carbon` feature flag (defaults to enabled) - Replaces the old \"Ultrathink no longer does anything. Thinking budget is now max by default.\" deprecation message **Evidence** Ultrathink effort injection (search for `\"ultrathink_effort\"`) \u2014 `rqY()` at line ~290076 checks `jd()` (`\"tengu_turtle_carbon\"`) and `Vf7()` (`\/\\bultrathink\\b\/i`)\n\n- Flag `tengu_turtle_carbon`: On for this account, and not off by default (read for one account on one subscription tier against v2.1.68; this account: on, anonymous baseline: on, compiled default: no gate table built for this version) 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."}