{"version":"2.1.257","anchor":"new-model-mythos-51-added-to-model-registry","canonical_anchor":"new-model-mythos-51-added-to-model-registry","heading":"New model: Mythos 5.1 added to model registry","tier":"soon","area":"Models","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.257\/e\/new-model-mythos-51-added-to-model-registry","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.257","markdown":"### New model: Mythos 5.1 added to model registry\n\nMythos 5.1 joins the model catalog with a 1M context window and effort levels up to max.\n\nA new model, Mythos 5.1 (`claude-mythos-5-1`), has been added to the model catalog. It ships with a 1M context window, support for effort levels up to `xhigh`\/`max`, and new capability flags including a dedicated prompt bundle.\n\n- Area: Models\n- Names: `claude-mythos-5-1`, `xhigh`, `max`\n- Tier: Nothing to try yet\n- Useful: 5\/5\n- Signal: 5\/5\n- Present in the build but not switched on"}