{"version":"2.1.305","anchor":"model-registry-sonnet-46-gains-maximum-window-1e6","canonical_anchor":"1m-context-window-metadata-maximum-window-and-clamp-flag-ad","heading":"Long-context window detection reworked, with new maximum_window and clamp fields","tier":"notice","area":"Models","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.305\/e\/model-registry-sonnet-46-gains-maximum-window-1e6","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.305","markdown":"### Long-context window detection reworked, with new maximum_window and clamp fields\n\nModel data gains maximum_window and clamp_long_context_without_beta, and the check for 1M context without opt-in now compares window sizes\n\n**What**\n\nThe context window is how much text a model can consider at once. Some models can reach 1 million tokens (1M).\n\n- The model schema accepts two new optional fields from remote config: `maximum_window` and `clamp_long_context_without_beta`.\n\n- Sonnet 4, Sonnet 4.6 and Opus 4.6 now carry `maximum_window: 1e6` (1 million). Sonnet 4 also has `clamp_long_context_without_beta` set.\n\n- The capability record replaces `has1mWithoutOptIn` and `unclampedButBilledPast200k` with `longContextWindowWithoutOptIn` and `apiContextWindowWithoutOptIn`.\n\n- The check for whether a window counts as long-context without opt-in now compares it with the larger of those two values instead of testing a fixed size and a yes\/no flag.\n\n- The long-context warning and the claude-desktop 1M notice now compare against a threshold instead of reading a yes\/no value.\n\n**Why**\n\nThis can change when a model is treated as having more than 200k context without opting in, which affects context limits, compaction and the 1M notice. The limits can now be adjusted from the server.\n\n- Area: Models\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: no"}