优化目录结构

tools.py

@@ -1,12 +1,8 @@
-import ast
 import asyncio
 from collections.abc import Callable
 from dataclasses import dataclass
 from datetime import datetime
 import json
-import math
-import operator
-from typing import Any
 from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
 from pydantic import BaseModel, ConfigDict, Field, ValidationError
@@ -18,12 +14,6 @@ class CurrentTimeArguments(BaseModel):
     timezone: str = Field(default="UTC", description="IANA timezone, e.g. Asia/Shanghai")
 
 
-class CalculatorArguments(BaseModel):
-    model_config = ConfigDict(extra="forbid")
-
-    expression: str = Field(description="Arithmetic expression to evaluate")
-
-
 @dataclass(frozen=True, slots=True)
 class ToolSpec:
     name: str
@@ -59,13 +49,7 @@ class ToolRegistry:
                 description="Get the current date and time in an IANA timezone.",
                 arguments_model=CurrentTimeArguments,
                 handler=_get_current_time,
-            ),
-            ToolSpec(
-                name="calculate",
-                description="Safely evaluate a basic arithmetic expression.",
-                arguments_model=CalculatorArguments,
-                handler=_calculate,
-            ),
+            )
         ]
         self._specs = {spec.name: spec for spec in specs}
 
@@ -118,54 +102,3 @@ def _get_current_time(arguments: BaseModel) -> dict[str, object]:
         raise ValueError("unknown timezone") from exc
     now = datetime.now(timezone)
     return {"timezone": arguments.timezone, "datetime": now.isoformat()}
-
-
-_BINARY_OPERATORS: dict[type[ast.operator], Callable[[Any, Any], Any]] = {
-    ast.Add: operator.add,
-    ast.Sub: operator.sub,
-    ast.Mult: operator.mul,
-    ast.Div: operator.truediv,
-    ast.FloorDiv: operator.floordiv,
-    ast.Mod: operator.mod,
-    ast.Pow: operator.pow,
-}
-_UNARY_OPERATORS: dict[type[ast.unaryop], Callable[[Any], Any]] = {
-    ast.UAdd: operator.pos,
-    ast.USub: operator.neg,
-}
-_MAX_EXPRESSION_LENGTH = 200
-_MAX_ABSOLUTE_RESULT = 1e100
-_MAX_EXPONENT = 100
-
-
-def _calculate(arguments: BaseModel) -> dict[str, object]:
-    assert isinstance(arguments, CalculatorArguments)
-    expression = arguments.expression.strip()
-    if not expression or len(expression) > _MAX_EXPRESSION_LENGTH:
-        raise ValueError("expression is empty or too long")
-    tree = ast.parse(expression, mode="eval")
-    result = _evaluate_node(tree.body)
-    if isinstance(result, float) and not math.isfinite(result):
-        raise ValueError("result is not finite")
-    if abs(result) > _MAX_ABSOLUTE_RESULT:
-        raise ValueError("result is too large")
-    return {"expression": expression, "result": result}
-
-
-def _evaluate_node(node: ast.AST) -> int | float:
-    if isinstance(node, ast.Constant):
-        if isinstance(node.value, bool) or not isinstance(node.value, (int, float)):
-            raise ValueError("only numeric constants are allowed")
-        return node.value
-    if isinstance(node, ast.UnaryOp) and type(node.op) in _UNARY_OPERATORS:
-        return _UNARY_OPERATORS[type(node.op)](_evaluate_node(node.operand))
-    if isinstance(node, ast.BinOp) and type(node.op) in _BINARY_OPERATORS:
-        left = _evaluate_node(node.left)
-        right = _evaluate_node(node.right)
-        if isinstance(node.op, ast.Pow) and abs(right) > _MAX_EXPONENT:
-            raise ValueError("exponent is too large")
-        result = _BINARY_OPERATORS[type(node.op)](left, right)
-        if abs(result) > _MAX_ABSOLUTE_RESULT:
-            raise ValueError("intermediate result is too large")
-        return result
-    raise ValueError("unsupported expression")