{
  "tools": [
    // 包含一个搜索工具（支持正则、BM25 或自定义实现）
    {"type": "tool_search_tool_regex_20251119", "name": "tool_search_tool_regex"},

    // 将工具标记为按需发现
    {
      "name": "github.createPullRequest",
      "description": "Create a pull request",
      "input_schema": {...},
      "defer_loading": true
    }
    // ... 更多标记了 defer_loading: true 的工具
  ]
}

{
  "type": "mcp_toolset",
  "mcp_server_name": "google-drive",
  "default_config": {"defer_loading": true},
  "configs": {
    "search_files": {
      "defer_loading": false
    }
  }
}

team = await get_team_members("engineering")

# Fetch budgets for each unique level
levels = list(set(m["level"] for m in team))
budget_results = await asyncio.gather(*[
    get_budget_by_level(level) for level in levels
])

# Create a lookup dictionary: {"junior": budget1, "senior": budget2, ...}
budgets = {level: budget for level, budget in zip(levels, budget_results)}

# Fetch all expenses in parallel
expenses = await asyncio.gather(*[
    get_expenses(m["id"], "Q3") for m in team
])

# Find employees who exceeded their travel budget
exceeded = []
for member, exp in zip(team, expenses):
    budget = budgets[member["level"]]
    total = sum(e["amount"] for e in exp)
    if total > budget["travel_limit"]:
        exceeded.append({
            "name": member["name"],
            "spent": total,
            "limit": budget["travel_limit"]
        })

print(json.dumps(exceeded))

{
  "tools": [
    {
      "type": "code_execution_20250825",
      "name": "code_execution"
    },
    {
      "name": "get_team_members",
      "description": "Get all members of a department...",
      "input_schema": {...},
      "allowed_callers": ["code_execution_20250825"]
    },
    {
      "name": "get_expenses",
      ...
    },
    {
      "name": "get_budget_by_level",
      ...
    }
  ]
}

{
  "type": "server_tool_use",
  "id": "srvtoolu_abc",
  "name": "code_execution",
  "input": {
    "code": "team = get_team_members('engineering')\n..."
  }
}

{
  "type": "tool_use",
  "id": "toolu_xyz",
  "name": "get_expenses",
  "input": {"user_id": "emp_123", "quarter": "Q3"},
  "caller": {
    "type": "code_execution_20250825",
    "tool_id": "srvtoolu_abc"
  }
}

{
  "type": "code_execution_tool_result",
  "tool_use_id": "srvtoolu_abc",
  "content": {
    "stdout": "[{\"name\": \"Alice\", \"spent\": 12500, \"limit\": 10000}...]"
  }
}

{
    "name": "create_ticket",
    "input_schema": { /* same schema as above */ },
    "input_examples": [
      {
        "title": "Login page returns 500 error",
        "priority": "critical",
        "labels": ["bug", "authentication", "production"],
        "reporter": {
          "id": "USR-12345",
          "name": "Jane Smith",
          "contact": {
            "email": "[email protected]",
            "phone": "+1-555-0123"
          }
        },
        "due_date": "2024-11-06",
        "escalation": {
          "level": 2,
          "notify_manager": true,
          "sla_hours": 4
        }
      },
      {
        "title": "Add dark mode support",
        "labels": ["feature-request", "ui"],
        "reporter": {
          "id": "USR-67890",
          "name": "Alex Chen"
        }
      },
      {
        "title": "Update API documentation"
      }
    ]
  }

// Good
{
    "name": "search_customer_orders",
    "description": "Search for customer orders by date range, status, or total amount. Returns order details including items, shipping, and payment info."
}

// Bad
{
    "name": "query_db_orders",
    "description": "Execute order query"
}

{
    "name": "get_orders",
    "description": "Retrieve orders for a customer.
Returns:
    List of order objects, each containing:
    - id (str): Order identifier
    - total (float): Order total in USD
    - status (str): One of 'pending', 'shipped', 'delivered'
    - items (list): Array of {sku, quantity, price}
    - created_at (str): ISO 8601 timestamp"
}

client.beta.messages.create(
    betas=["advanced-tool-use-2025-11-20"],
    model="claude-sonnet-4-5-20250929",
    max_tokens=4096,
    tools=[
        {"type": "tool_search_tool_regex_20251119", "name": "tool_search_tool_regex"},
        {"type": "code_execution_20250825", "name": "code_execution"},
        # Your tools with defer_loading, allowed_callers, and input_examples
    ]
)