00:01 Seed S-hidden 00:33 Settings > General > New threads > Model. Row: "Claude Fable 5.1 · High" 00:36 settings.json defaultModelSelection = {"instanceId":"claudeAgent","model":"claude-opus-4-8","options":[{"id":"effort","value":"high"}]} 00:39 Open the effort picker (currently "High") 00:42 Choose Low 00:46 Picked Low. settings.json now {"instanceId":"claudeAgent","model":"claude-fable-5-1","options":[{"id":"effort","value":"low"}]} 00:48 Reload the page 01:11 After reload. Row: "Claude Fable 5.1 · Low" 01:13 jq .defaultModelSelection settings.json -> {"instanceId":"claudeAgent","model":"claude-fable-5-1","options":[{"id":"effort","value":"low"}]}