{
 "name": "Claude Fable 5",
 "vendor": "Anthropic",
 "model_id": "claude-fable-5",
 "model_id_note": "Use this exact string. No date suffix exists.",
 "released": "2026-06-09",
 "tier": "Above Opus \u2014 Anthropic's most intelligent model. A Mythos-class model made safe for general use.",
 "context_window_tokens": 1000000,
 "max_output_tokens": 128000,
 "streaming_required_above_output_tokens": 16000,
 "pricing_per_million_tokens_usd": {
  "input": 10.0,
  "output": 50.0
 },
 "pricing_comparison_per_million_tokens_usd": {
  "claude-opus-4-8": {
   "input": 5.0,
   "output": 25.0
  },
  "claude-sonnet-4-6": {
   "input": 3.0,
   "output": 15.0
  },
  "claude-haiku-4-5": {
   "input": 1.0,
   "output": 5.0
  }
 },
 "thinking": {
  "mode": "adaptive_only",
  "enable": {
   "thinking": {
    "type": "adaptive"
   }
  },
  "disable": "Omit the thinking field entirely. An explicit {\"type\": \"disabled\"} returns HTTP 400 (Fable-specific).",
  "display_default": "omitted",
  "display_visible_reasoning": {
   "thinking": {
    "type": "adaptive",
    "display": "summarized"
   }
  }
 },
 "effort": {
  "parameter": "output_config.effort",
  "levels": [
   "low",
   "medium",
   "high",
   "xhigh",
   "max"
  ],
  "default": "high",
  "recommended": {
   "coding_and_agentic": "xhigh",
   "general": "high",
   "correctness_critical": "max"
  }
 },
 "structured_outputs": true,
 "prompt_caching": {
  "supported": true,
  "minimum_cacheable_prefix_tokens": 2048
 },
 "task_budgets": {
  "beta_header": "task-budgets-2026-03-13",
  "parameter": "output_config.task_budget",
  "minimum_total_tokens": 20000
 },
 "vision": "State-of-the-art, high-resolution image input",
 "availability": {
  "api": "Fully available from 2026-06-09",
  "consumption_enterprise": "Fully available from 2026-06-09",
  "subscriptions_included_free": {
   "from": "2026-06-09",
   "to": "2026-06-22"
  },
  "subscriptions_usage_credits_from": "2026-06-23",
  "claude_code": "Fable 5 powers Claude Code (CLI, desktop, web, IDE extensions)"
 },
 "mythos_5": {
  "what": "Same underlying model with safeguards lifted in specific areas",
  "access": "Restricted: Project Glasswing partners (cyber), select biology researchers (bio/chem); broader trusted-access program planned",
  "data_retention_days": 30,
  "generally_available": false
 },
 "sources": [
  "https://www.anthropic.com/news/claude-fable-5-mythos-5",
  "https://platform.claude.com/docs"
 ],
 "disclaimer": "Independent guide, not affiliated with Anthropic. Verify against platform.claude.com/docs.",
 "last_verified": "2026-06-10",
 "version": "1.0.0",
 "dateModified": "2026-06-10"
}