previous_trading_day
Find the previous trading day for China's A-share market to calculate accurate date-based financial metrics and analysis.
Instructions
Get the previous trading day before the given date.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| date | Yes |
Implementation Reference
- src/tools/date_utils.py:45-51 (handler)MCP tool handler function for 'previous_trading_day'. Decorated with @app.tool() for registration and execution. Delegates to the use case layer's previous_trading_day function via run_tool_with_handling for error handling and logging.
@app.tool() def previous_trading_day(date: str) -> str: """Get the previous trading day before the given date.""" return run_tool_with_handling( lambda: uc_date.previous_trading_day(active_data_source, date=date), context=f"previous_trading_day:{date}", ) - src/use_cases/date_utils.py:64-70 (helper)Core implementation of previous_trading_day logic. Fetches trading days from the data source around the given date and returns the most recent trading day strictly before the input date, or the input date if none found.
def previous_trading_day(data_source: FinancialDataSource, *, date: str) -> str: target = datetime.strptime(date, "%Y-%m-%d") start = (target - timedelta(days=31)).strftime("%Y-%m-%d") df = _fetch_trading_days(data_source, start_date=start, end_date=date) days = df[df["is_trading_day"] == "1"]["calendar_date"].tolist() prev = max([d for d in days if d < date], default=None) return prev or date - mcp_server.py:56-56 (registration)Top-level registration call in the main MCP server file that registers the date_utils tools module, including the previous_trading_day tool.
register_date_utils_tools(app, active_data_source)