ida-mcp-server

Instructions

Implementation Reference

• plugin/ida_mcp_server_plugin/ida_mcp_core.py:549-587 (handler)

  Core handler that implements the tool logic: iterates over rename pairs, calls single rename internal function for each, collects success/failure stats.

  def rename_multi_local_variables(self, function_name: str, rename_pairs_old2new: List[Dict[str, str]]) -> Dict[str, Any]:
      """Rename multiple local variables within a function at once"""
      try:
          success_count: int = 0
          failed_pairs: List[Dict[str, str]] = []
  
          for pair in rename_pairs_old2new:
              old_name = next(iter(pair.keys()))
              new_name = pair[old_name]
              
              # Call existing rename_local_variable_internal for each pair
              result = self._rename_local_variable_internal(function_name, old_name, new_name)
              
              if result.get("success", False):
                  success_count += 1
              else:
                  failed_pairs.append({
                      "old_name": old_name,
                      "new_name": new_name,
                      "error": result.get("message", "Unknown error")
                  })
  
          return {
              "success": True,
              "message": f"Renamed {success_count} out of {len(rename_pairs_old2new)} local variables",
              "success_count": success_count,
              "failed_pairs": failed_pairs
          }
  
      except Exception as e:
          print(f"Error in rename_multi_local_variables: {str(e)}")
          traceback.print_exc()
          return {
              "success": False,
              "message": str(e),
              "success_count": 0,
              "failed_pairs": rename_pairs_old2new
          }

• plugin/ida_mcp_server_plugin/ida_mcp_core.py:483-546 (helper)

  Supporting function that performs the actual single local variable rename using IDA Hex-Rays decompiler API: decompiles function, finds lvar, calls ida_hexrays.rename_lvar.

  def _rename_local_variable_internal(self, function_name: str, old_name: str, new_name: str) -> Dict[str, Any]:
      """Internal implementation for rename_local_variable without sync wrapper"""
      try:
          # Parameter validation
          if not function_name:
              return {"success": False, "message": "Function name cannot be empty"}
          if not old_name:
              return {"success": False, "message": "Old variable name cannot be empty"}
          if not new_name:
              return {"success": False, "message": "New variable name cannot be empty"}
          
          # Get function address
          func_addr: int = ida_name.get_name_ea(0, function_name)
          if func_addr == idaapi.BADADDR:
              return {"success": False, "message": f"Function '{function_name}' not found"}
          
          # Check if it's a function
          func: Optional[ida_funcs.func_t] = ida_funcs.get_func(func_addr)
          if not func:
              return {"success": False, "message": f"'{function_name}' is not a function"}
          
          # Check if decompiler is available
          if not ida_hexrays.init_hexrays_plugin():
              return {"success": False, "message": "Hex-Rays decompiler is not available"}
          
          # Get decompilation result
          cfunc: Optional[ida_hexrays.cfunc_t] = ida_hexrays.decompile(func_addr)
          if not cfunc:
              return {"success": False, "message": f"Failed to decompile function '{function_name}'"}
          
          ida_hexrays.open_pseudocode(func_addr, 0)
          
          # Find local variable to rename
          found: bool = False
          renamed: bool = False
          lvar: Optional[ida_hexrays.lvar_t] = None
          
          # Iterate through all local variables
          lvars = cfunc.get_lvars()
          for i in range(lvars.size()):
              v = lvars[i]
              if v.name == old_name:
                  lvar = v
                  found = True
                  break
          
          if not found:
              return {"success": False, "message": f"Local variable '{old_name}' not found in function '{function_name}'"}
          
          # Rename local variable
          if ida_hexrays.rename_lvar(cfunc.entry_ea, lvar.name, new_name):
              renamed = True
          
          if renamed:
              # Refresh view
              self._refresh_view_internal()
              return {"success": True, "message": f"Local variable renamed from '{old_name}' to '{new_name}' in function '{function_name}'"}
          else:
              return {"success": False, "message": f"Failed to rename local variable from '{old_name}' to '{new_name}', possibly due to invalid name format or other IDA restrictions"}
      
      except Exception as e:
          print(f"Error renaming local variable: {str(e)}")
          traceback.print_exc()
          return {"success": False, "message": str(e)}

• src/mcp_server_ida/server.py:55-58 (schema)

  Pydantic schema defining input for the MCP tool: function name and list of old-to-new name pairs.

  class RenameMultiLocalVariables(BaseModel):
      function_name: str
      rename_pairs_old2new: List[Dict[str, str]]  # List of dictionaries with "old_name" and "new_name" keys

• src/mcp_server_ida/server.py:973-977 (registration)

  MCP tool registration in @server.list_tools(): defines name, description, and input schema.

  Tool(
      name=IDATools.RENAME_MULTI_LOCAL_VARIABLES,
      description="Rename multiple local variables within a function at once in the IDA database",
      inputSchema=RenameMultiLocalVariables.schema(),
  ),

• plugin/ida_mcp_server_plugin.py:255-259 (registration)

  Dispatch/registration in IDA socket server: handles 'rename_multi_local_variables' request type by calling core handler.

  elif request_type == "rename_multi_local_variables":
      response.update(self.core.rename_multi_local_variables(
          request_data.get("function_name", ""),
          request_data.get("rename_pairs_old2new", [])
      ))