Title	Author	Date
Universal Chess Interface Specification	blocr	Feb 18, 2023

Universal Chess Interface Specification

Introduction

The Universal Chess Interface (UCI) is a communication protocol used between chess engines and chess user interfaces (GUI). UCI was created and first release in November 2000 by Rudolf Huber and Stefan Meyer-Kahlen

Move format

Moves are written in long algebraic notation

Long Algebraic Notation (LAN)

Long Algebraic Notation specify both the starting and ending square

e2e4

move the piece from the square e2 to the square e4

f3g5

move the piece from the square f3 to the square g5

Engine

• uci
• debug [on|off]
• isready
• setoption name [value]
• register
• ucinewgame
• position [fen|startpos] moves ...
• go
  • ponder
  • wtime
  • btime
  • winc
  • binc
  • movestogo
  • depth
  • nodes
  • mate
  • infinite
• stop
• ponderhit
• quit

User Interface

• id
  • name
  • author
• uciok
• readyok
• bestmove [ponder]
• copyprotection
• registration
• info
  • depth
  • seldepth
  • time
  • nodes
  • pv
  • multipv
  • score
    • cp
    • mate
    • lowerbound
    • upperbound
  • currmove
  • currmovenumber
  • hashfull
  • nps
  • tbhits
  • cpuload
  • string
  • refutation
  • currline
• option
  • name
  • type
  • default
  • min
  • max
  • var

Examples