Chess TCN Python is a Python package that provides functionality to encode and decode TCN, a move format used by Chess.com. This package is ideal for developers looking to work with TCN in Python applications.
TCN is a format used by Chess.com to transmit move lists in its JSON API. A typical endpoint for retrieving a game’s move list is:
https://www.chess.com/callback/live/game/{gameId}
This endpoint returns a moveList field containing a TCN string.
- Decode TCN strings into PGN (Portable Game Notation).
- Encode PGN back into TCN format.
To install the package, use pip:
pip install chess-tcnHere’s a quick example of how to use the package:
from chess_tcn import decode_tcn, encode_tcn, tcn_to_pgn, pgn_to_tcn
# Example TCN string (e.g. from Chess.com live‐game API)
tcn_string = "mC0Kgv7Tbq5Qlt9IqHT7cM1TMFWOHs2MFwZRfm6Eeg"
# Decode TCN to a list of move dicts
moves = decode_tcn(tcn_string)
print("Decoded moves (dicts):", moves)
# Re-encode that move list back into a TCN string
reencoded_tcn = encode_tcn(moves)
print("Re-encoded TCN string:", reencoded_tcn)
# Convert the TCN string directly to a PGN move-text string
pgn_text = tcn_to_pgn(tcn_string)
print("PGN move-text:", pgn_text)
# Convert a PGN move-text string back into TCN
roundtrip_tcn = pgn_to_tcn(pgn_text)
print("TCN from PGN:", roundtrip_tcn)For complete details on usage, check out the documentation.
This project is licensed under the MIT License. See below for full text.
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