Every major LLM provider's deprecation, shutdown, and breaking-change events — one normalized timeline.https://ai-model-change-radar-west0ngs-projects.vercel.app/en-ushttps://platform.claude.com/docs/en/about-claude/model-deprecationshttps://platform.claude.com/docs/en/about-claude/model-deprecationsStandard API requests to claude-3-opus-20240229 fail; access only by special request afterward. Replacement: Claude Opus 4.1 Source: https://platform.claude.com/docs/en/about-claude/model-deprecationsMon, 30 Jun 2025 00:00:00 GMThttps://openai.com/index/retiring-gpt-4o-and-older-models/https://openai.com/index/retiring-gpt-4o-and-older-models/Model picker entries disappear; saved chats on these models silently switch to GPT-5.2. ~2 weeks notice. Replacement: GPT-5.2 (existing chats default to GPT-5.2) Source: https://openai.com/index/retiring-gpt-4o-and-older-models/Thu, 29 Jan 2026 00:00:00 GMThttps://developers.openai.com/api/docs/deprecationshttps://developers.openai.com/api/docs/deprecationsApps pinned to the floating chatgpt-4o-latest alias start erroring; must pin a dated snapshot or migrate. Replacement: A dated GPT-4o snapshot or a GPT-5.x model Source: https://developers.openai.com/api/docs/deprecationsTue, 18 Nov 2025 00:00:00 GMThttps://platform.claude.com/docs/en/about-claude/model-deprecationshttps://platform.claude.com/docs/en/about-claude/model-deprecationsAll API requests to claude-3-haiku-20240307 return an error after 2026-04-19. Replacement: Claude Haiku 4.5 (model ID + parameter changes required, not a pure drop-in) Source: https://platform.claude.com/docs/en/about-claude/model-deprecationsSun, 19 Apr 2026 00:00:00 GMThttps://docs.x.ai/developers/migration/may-15-retirementhttps://docs.x.ai/developers/migration/may-15-retirementHard-coded Grok model IDs silently reroute to grok-4.3 with different behavior and pricing. Only 9 days notice. Replacement: grok-4.3 (grok-imagine-image-pro → grok-imagine-image-quality) Source: https://docs.x.ai/developers/migration/may-15-retirementWed, 06 May 2026 00:00:00 GMThttps://ai.google.dev/gemini-api/docs/deprecationshttps://ai.google.dev/gemini-api/docs/deprecationsgemini-2.0-flash / -lite calls fail; replacement costs ~33% more. New customers already cut off. Replacement: Gemini 2.5 Flash-Lite (~33% price increase; updated knowledge cutoff & 8x output limit) Source: https://ai.google.dev/gemini-api/docs/deprecationsWed, 18 Feb 2026 00:00:00 GMThttps://platform.claude.com/docs/en/about-claude/model-deprecationshttps://platform.claude.com/docs/en/about-claude/model-deprecationsRequests to the Opus 4 / Sonnet 4 model IDs fail after 2026-06-15. Replacement: claude-opus-4-6 / claude-sonnet-4-6 (one-line ID swap, but re-test streaming, structured output, long-context) Source: https://platform.claude.com/docs/en/about-claude/model-deprecationsMon, 15 Jun 2026 00:00:00 GMThttps://developers.openai.com/api/docs/assistants/migrationhttps://developers.openai.com/api/docs/assistants/migrationEntire Assistants/Threads/Runs surface stops working. Manual backfill of conversation history required. Replacement: Responses API + Conversations API (no automated Threads→Conversations migration tool) Source: https://developers.openai.com/api/docs/assistants/migrationTue, 26 Aug 2025 00:00:00 GMT