{"version":"2.1.288","anchor":"auto-mode-classifier-ignores-anthropic-default-sonnet-model","canonical_anchor":"auto-mode-classifier-ignores-anthropic-default-sonnet-model","heading":"Auto mode ignores an excluded model set in ANTHROPIC_DEFAULT_SONNET_MODEL","tier":"notice","area":"Auto Mode","scope":"both","heads_up":true,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.288\/e\/auto-mode-classifier-ignores-anthropic-default-sonnet-model","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.288","markdown":"### Auto mode ignores an excluded model set in `ANTHROPIC_DEFAULT_SONNET_MODEL`\n\nIf `ANTHROPIC_DEFAULT_SONNET_MODEL` names an excluded model, auto mode's classifier uses the Sonnet 5 default and logs the reason once\n\n**Unclear.** Which models are on the exclusion list is not stated.\n\n**What**\n\n`ANTHROPIC_DEFAULT_SONNET_MODEL` is an environment variable, a setting passed to Claude Code by the shell it starts from. It sets which model the `sonnet` alias stands for. Auto mode also uses it to choose the model for its classifier.\n\nIf the variable names a model that is on an exclusion list, Claude Code now drops it for the classifier and uses the Sonnet 5 default instead. It logs the reason once. Before, any model that passed the usual validity check was used.\n\n**Why**\n\nThis matters if you use auto mode and pin the Sonnet model, for example on a third-party provider. The classifier may now run on a different model from the one you set.\n\n- Area: Auto Mode\n- Names: `ANTHROPIC_DEFAULT_SONNET_MODEL`\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: both\n- Heads-up: yes"}