Usage

Once you have compiled the engine, you can use it either through a Graphical User Interface (GUI) or directly via the Command Line Interface (CLI).

Using with a Chess GUI#

FollyChess is a UCI-compatible engine, meaning it does not have its own graphics. Instead, it “plugs into” a chess interface. We recommend using one of these GUIs:

• Arena
• BanksiaGUI
• Cutechess
• HIARCS Chess Explorer

In your GUI of choice, add a new engine and select the bazel-bin/cli/follychess binary when prompted.

Running via CLI#

You can interact with the engine directly via standard input for debugging or scripting.

bazel-bin/cli/follychess

Once running, the engine waits for commands from standard input. FollyChess currently supports a subset of the UCI protocol. Supported commands are covered below.

uci#

Initializes the UCI protocol. The engine will identify itself and list its available options.

isready#

Used to synchronize with the engine. FollyChess will respond with readyok once it has finished internal setup and is ready to receive move or search commands.

d#

Custom Command. Displays the current position:

d
8: r n b q k b n r
7: p p p p p p p p
6: . . . . . . . .
5: . . . . . . . .
4: . . . . . . . .
3: . . . . . . . .
2: P P P P P P P P
1: R N B Q K B N R
   a b c d e f g h

   w KQkq - 0 1

position#

This command tells the engine what the board looks like. It supports these formats:

• Starting Position: position startpos sets the board to the starting position:

    position startpos
    d
    8: r n b q k b n r
    7: p p p p p p p p
    6: . . . . . . . .
    5: . . . . . . . .
    4: . . . . . . . .
    3: . . . . . . . .
    2: P P P P P P P P
    1: R N B Q K B N R
       a b c d e f g h
  
    w KQkq - 0 1

• FEN String: position fen <fenstring> sets the board to a specific state using Forsyth-Edwards Notation:

    position fen 8/2p5/3p4/KP5r/1R3p1k/8/4P1P1/8 w - - 0 1
    d
    8: . . . . . . . .
    7: . . p . . . . .
    6: . . . p . . . .
    5: K P . . . . . r
    4: . R . . . p . k
    3: . . . . . . . .
    2: . . . . P . P .
    1: . . . . . . . .
       a b c d e f g h
  
    w - - 0 1

• Adding Moves: position [startpos | fen <fenstring>] moves <move1> <move2> ... applies a sequence of moves to the specified position:

  position startpos moves e2e4 e7e5 g1f3
  d
  8: r n b q k b n r
  7: p p p p . p p p
  6: . . . . . . . .
  5: . . . . p . . .
  4: . . . . P . . .
  3: . . . . . N . .
  2: P P P P . P P P
  1: R N B Q K B . R
     a b c d e f g h
  
  b KQkq - 3 2

Moves use long algebraic notation:

go#

Calculates the best move with a user-specified depth:

go depth 3
info depth 3 seldepth 3 nodes 1024 nps 175402 tbhits 36
info depth 3 seldepth 4 nodes 2048 nps 241766 tbhits 133
info depth 3 seldepth 3 nodes 3072 nps 286567 tbhits 166
info depth 3 seldepth 3 nodes 4096 nps 286033 tbhits 187
info depth 3 seldepth 3 nodes 5120 nps 310058 tbhits 264
bestmove b1c3

quit#

Terminates the engine process.