Toledo NanoChess is originally a killer chess engine because it is the smallest one in the world ! The quality of the code within so few bytes is totally incredible.

This UCI version is a derivative work of the library Toledo NanoChess released in 2013 for JavaScript. It has some benefits :

• Play with a desktop application through the modern UCI protocol.
• Undo the last move without losing your game.
• With pyChess' slider, select the strength of the AI when you start a new game (6 is a good value).
• Toledo plays both White and Black.
• Play Chess960 with unsupported castling.
• Information about the analysis : processing time, nodes, nodes per second...

Despite it was coded and tested in just three days, this UCI port doesn't aim to be the smallest one in the world... ;-)

First, install NodeJS.org which is the host application to run the script.

For pyChess, just add toledo-uci.js to the list of engines.

For WinBoard, add this new line in the engine list :

"Toledo NanoChess UCI" -fcp 'C:\full-path-to\node.exe "C:\full-path-to\toledo-uci.js"' -fn "Toledo NanoChess UCI" -fUCI

For the command line, execute node toledo-uci.js.

Refer to the header of the main JavaScript file to know more about the license.

• uci
• setoption name Skill Level value (number) where (number) is a level between 1 and 20
• isready
• ucinewgame
• position startpos
• position startpos moves (string) with as many moves written in UCI format (like e2e3) as needed
• position fen (string) where (string) is a complete position in FEN format
• position fen (string) moves (string)
• debug displays Toledo NanoChess' internal variables
• debug move (string) where (string) is a move to perform written in UCI format (like a2a1q)
• debug board displays the internal board
• debug quality executes the automated quality check
• go
• go depth (number) where (number) is the forced depth to reach (it temporarily overrides the current strength of the AI)
• quit

Any other command is unsupported (like stop) or partially ignored (like go infinite).