testsAndMisc/PYTHON/lichess_bot

Lichess Bot (minimal)

A small Lichess BOT that accepts standard challenges and plays quick random legal moves using python-chess. It demonstrates the Lichess Board API basics with a simple, readable implementation.

Features

• Connects to Lichess Board API via streaming NDJSON
• Accepts only standard chess challenges (bullet/blitz/rapid/classical)
• Spawns a thread per active game
• Plays random legal moves (swap in a stronger engine later)
• Simple logging and basic retries on transient network errors

Requirements

• Python 3.9+
• A Lichess account that is activated as a BOT
• A Lichess API access token with at least the scopes:
  • bot:play
  • challenge:read
  • challenge:write

Install dependencies:

pip install -r PYTHON/lichess_bot/requirements.txt

Activate BOT and get a token

1. Create or use an existing Lichess account for your bot.
2. Activate it as a BOT (one-time): https://lichess.org/api#tag/Bot
   • If not already BOT, you need to convert the account; follow Lichess docs.
3. Create a personal API token: https://lichess.org/account/oauth/token/create
   • Grant scopes: bot:play, challenge:read, challenge:write

Export the token in your shell (recommended):

export LICHESS_TOKEN="your_bot_token_here"

Run

From the repo root:

python -m PYTHON.lichess_bot.main

Optional flags:

• --log-level INFO|DEBUG|WARNING|ERROR (default: INFO)
• --decline-correspondence (declines correspondence challenges)

You can also use the helper script:

bash PYTHON/lichess_bot/run.sh

Notes

• The engine is intentionally weak (random moves). Swap it with a UCI engine or implement a better search in engine.py.
• Network calls hit real Lichess endpoints. Keep the bot polite; respect rate limits.

Development

• Small unit tests are in tests/ and only cover local helpers (no network). Run:

python -m pytest PYTHON/lichess_bot/tests -q

If you add tests requiring third-party packages, install them in your environment first.