{
  "id": 18705537,
  "title": "Claude Haiku 5.5 400 Error? 5 Fixes That Work (2026)",
  "url": "https://urgent.news/2026/11/07/claude-haiku-5-5-400-error-5-fixes-that-work-2026",
  "topic": "tech",
  "section": "Tech",
  "published": "2026-11-07T12:01:18.000Z",
  "source": {
    "name": "Dev.to",
    "slug": "dev-to",
    "url": "https://dev.to/theglitchfixer/claude-haiku-55-400-error-5-fixes-that-work-2026-2f59"
  },
  "original_language": "en",
  "account": "Claude Haiku 5.5 throws 400 errors when model ID changes from Haiku 4.5, breaking integrated requests. Anthropic's migration guide documents fixes in five categories: budget budgeting, parameter removals, message formatting, toolset updates, and history editing. To fix breakdowns, update model ID, switch thinking to adaptive or disabled, drop temperature/top_p/top_k, use tools instead of computer tool, and avoid editing history. Anthropic's October 2026 pricing confirms the $0.10/1M input token tier for Haiku 5.5, up from Haiku 4.5's $0.10.",
  "summary": "Claude Haiku 5.5 400 Error? 5 Fixes That Work (2026) Last updated: October 31, 2026 Short answer: Changing only the model ID to Claude Haiku 5.5 can turn a working integration red, because requests that worked yesterday now return 400 Bad Request. The breaks are documented and each has a fix, and this guide covers the five changes that throw a 400, the three that fail silently, and the pricing…",
  "key_points": [
    "Claude Haiku 5.5 generates 400 errors when model ID changes",
    "Anthropic's migration guide provides five fix categories",
    "October 2026 pricing confirms $0.10/1M input token tier for Haiku 5.5"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}