Redis MCP Server

Instructions

Implementation Reference

• src/tools/string.py:11-49 (handler)

  Handler for the 'set' tool: sets a Redis string key with optional expiration using Redis SET or SETEX.

  @mcp.tool()
  async def set(
      key: str,
      value: Union[str, bytes, int, float, dict],
      expiration: Optional[int] = None,
  ) -> str:
      """Set a Redis string value with an optional expiration time.
  
      Args:
          key (str): The key to set.
          value (str, bytes, int, float, dict): The value to store.
          expiration (int, optional): Expiration time in seconds.
  
      Returns:
          str: Confirmation message or an error message.
      """
      if isinstance(value, bytes):
          encoded_value = value
      elif isinstance(value, dict):
          encoded_value = json.dumps(value)
      else:
          encoded_value = str(value)
  
      if isinstance(encoded_value, str):
          encoded_value = encoded_value.encode("utf-8")
  
      try:
          r: Redis = RedisConnectionManager.get_connection()
          if expiration:
              r.setex(key, expiration, encoded_value)
          else:
              r.set(key, encoded_value)
  
          return f"Successfully set {key}" + (
              f" with expiration {expiration} seconds" if expiration else ""
          )
      except RedisError as e:
          return f"Error setting key {key}: {str(e)}"