random_int

Instructions

Implementation Reference

• src/random_number_mcp/tools.py:15-33 (handler)

  The actual implementation of the random_int tool. Validates inputs via validate_range helper and calls random.randint(low, high).

  def random_int(low: int, high: int) -> int:
      """Generate a random integer between low and high (inclusive).
  
      Args:
          low: Lower bound (inclusive)
          high: Upper bound (inclusive)
  
      Returns:
          Random integer between low and high
  
      Raises:
          ValueError: If low > high
          TypeError: If inputs are not integers
      """
      if not isinstance(low, int) or not isinstance(high, int):
          raise TypeError("Both low and high must be integers")
  
      validate_range(low, high)
      return random.randint(low, high)

• src/random_number_mcp/server.py:13-24 (registration)

  Registers random_int as an MCP tool via @app.tool() decorator on FastMCP. Delegates to tools.random_int.

  @app.tool()
  def random_int(low: int, high: int) -> int:
      """Generate a random integer between low and high (inclusive).
  
      Args:
          low: Lower bound (inclusive)
          high: Upper bound (inclusive)
  
      Returns:
          Random integer between low and high
      """
      return tools.random_int(low, high)

• src/random_number_mcp/utils.py:6-9 (helper)

  The validate_range helper used by random_int to ensure low <= high.

  def validate_range(low: int | float, high: int | float) -> None:
      """Validate that low <= high for range-based functions."""
      if low > high:
          raise ValueError(f"Low value ({low}) must be <= high value ({high})")

• tests/test_tools.py:22-50 (schema)

  Tests for random_int, covering basic usage, same bounds, negative ranges, invalid ranges, and non-integer inputs. Effectively documents the expected input/output contract.

  class TestRandomInt:
      """Tests for random_int function."""
  
      def test_random_int_basic(self):
          """Test basic random integer generation."""
          result = random_int(1, 10)
          assert isinstance(result, int)
          assert 1 <= result <= 10
  
      def test_random_int_same_bounds(self):
          """Test random integer with same low and high."""
          result = random_int(5, 5)
          assert result == 5
  
      def test_random_int_negative_range(self):
          """Test random integer with negative range."""
          result = random_int(-10, -1)
          assert isinstance(result, int)
          assert -10 <= result <= -1
  
      def test_random_int_invalid_range(self):
          """Test random integer with invalid range."""
          with pytest.raises(ValueError, match="Low value .* must be <= high value"):
              random_int(10, 5)
  
      def test_random_int_non_integer_input(self):
          """Test random integer with non-integer input."""
          with pytest.raises(TypeError, match="Both low and high must be integers"):
              random_int(1.5, 10)

• examples/demo_host.py:84-90 (helper)

  Example usage demonstrating how to call random_int via the MCP client.

  # Demo random_int
  print("\n1. random_int - Generate random integers")
  result = await client.call_tool("random_int", {"low": 1, "high": 100})
  print(f"   Random integer (1-100): {result}")
  
  result = await client.call_tool("random_int", {"low": -10, "high": 10})
  print(f"   Random integer (-10 to 10): {result}")