{
  "model_name": "Claude Sonnet 4.5",
  "model_organization": "Anthropic",
  "submitting_organization": "Sierra",
  "submission_date": "2026-02-26",
  "contact_info": {
    "email": "victor@sierra.ai, ben.s@sierra.ai",
    "name": "Sierra Research Team"
  },
  "is_new": false,
  "submission_type": "standard",
  "trajectories_available": true,
  "trajectory_files": {
    "airline": "claude-sonnet-4-5_enabled_airline_gpt-5.2_4trials.json",
    "retail": "claude-sonnet-4-5_enabled_retail_gpt-5.2_4trials.json",
    "telecom": "claude-sonnet-4-5_enabled_telecom_gpt-5.2_4trials.json",
    "banking_knowledge": "claude-sonnet-4-5_enabled_banking_knowledge_gpt-5.2_4trials.json"
  },
  "references": [],
  "results": {
    "airline": {
      "pass_1": 72.0,
      "pass_2": 62.0,
      "pass_3": 54.5,
      "pass_4": 48.0,
      "cost": 0.29646
    },
    "retail": {
      "pass_1": 72.37,
      "pass_2": 57.46,
      "pass_3": 47.37,
      "pass_4": 39.47,
      "cost": 0.25494
    },
    "telecom": {
      "pass_1": 84.87,
      "pass_2": 75.44,
      "pass_3": 68.86,
      "pass_4": 64.04,
      "cost": 0.48769
    },
    "banking_knowledge": {
      "pass_1": 25.26,
      "pass_2": 15.81,
      "pass_3": 12.63,
      "pass_4": 10.31,
      "cost": 4.04814,
      "retrieval_config": "terminal"
    }
  },
  "reasoning_effort": "enabled",
  "methodology": {
    "evaluation_date": "2026-02-24",
    "tau2_bench_version": "1.0.1",
    "user_simulator": "gpt-5.2",
    "notes": "Evaluated using Claude Sonnet 4.5 (claude-sonnet-4-5-20250929) with extended thinking enabled. User simulator: gpt-5.2 with reasoning_effort: low. 4 trials. Seed: 300. Banking domain evaluated with terminal-based agentic search retrieval. banking_knowledge re-graded under tau2-bench v1.0.1 grading fixes on 2026-07-15 (extra-read logging #329, numeric-argument normalization #397, T077-T086 gold trajectories #402); scores prior to v1.0.1 are not comparable.",
    "verification": {
      "modified_prompts": false,
      "omitted_questions": false,
      "details": "Verified evaluation with full trajectory data available. Standard tau-bench scaffold."
    }
  },
  "model_release": {
    "release_date": "2025-09-29",
    "announcement_url": "https://www.anthropic.com/news/claude-sonnet-4-5",
    "announcement_title": "Introducing Claude Sonnet 4.5"
  }
}