---
name: stockfish-desk
description: "Knowledge for playing, planning and analysing chess against the Stockfish engine, from Stockfish Exchange's ten-agent war room: what Stockfish is, how its Skill Level handicap behaves, lessons and plans from 15 live games (PGNs included), prompts for a strategy desk, and an MCP server / HTTP API that returns Stockfish's best move and evaluation for any position. Use when asked to play or beat Stockfish, to analyse a chess position with an engine, or to set up a chess strategy desk."
metadata:
  source: https://stockfish.finance
  generated: 2026-10-28T20:05:53.683Z
  games: 15
  record: Claude 0 · draws 0 · Stockfish 269
---

# Stockfish desk

The war room at https://stockfish.finance plays Claude against Stockfish at handicapped Skill Levels, live, and writes down what it learns. This skill packages that knowledge together with a way to consult the engine itself.

## Files

- `knowledge.md` — read this first: what Stockfish is, how Skill Levels behave, results by level and colour, the lessons and the current plan.
- `lessons.json` — the same, structured (lessons per agent, plans, results, game index).
- `games.pgn` — every exhibition game with headers (level, colours, result, reason, plan).
- `prompts/player.md` — the player's system prompt and its move contract (JSON, one legal move + a remark).
- `prompts/war-room.md` — the ten strategists, the meeting protocol and the plan schema, ready to run in any LLM.
- `tools/stockfish-mcp.mjs` — MCP server: `analyse_position` (best move + eval from Stockfish) and `desk_knowledge`.

## How to use

1. **Playing against Stockfish** at a given level: read the Skill Level section and the lessons in `knowledge.md`, adopt the current plan (or run the desk from `prompts/war-room.md` to write a new one), then play with the contract in `prompts/player.md`: only ever answer with a move from the legal-move list you were given, and check checks, captures and hanging pieces before committing.
2. **Analysing a position**: use the MCP tool `analyse_position` or POST to `https://stockfish.finance/api/analyse` with a FEN and/or moves. Trust the engine's evaluation over your own; it is never handicapped.
3. **Studying**: `games.pgn` loads into any chess GUI or library; `lessons.json` is easy to filter by level.

## Rules of thumb the desk has paid for

- General: When material starts disappearing via simplification (queen trade, bishop trades) in a slightly worse position, recalculate king safety immediately - open g/h files near your king are fatal even against lower-level engines.
- General: In the Caro-Kann Advance, don't let the dark-square bishop get trapped/traded awkwardly (Bh6 hit my rook); keep escape squares and watch for Bh6-type pins on f6/g7 structure after ...gxf6.
- Caro-Kann with ...Bf5 then ...Bd3 traded off my good bishop for nothing while allowing cxd3 to repair White's structure - avoid trading a strong developed piece without clear gain.
- General: When king is on f1/g1 after castling, keep an eye on diagonal/file checks from bishops or queens that could combine into a material-winning sequence; don't assume one tactical shot is the end of danger.
- General: Before playing moves like Qd2 that leave h2 undefended, check if opponent's queen can infiltrate with check (e.g., Qxh2+) and what follow-up checks (like Bc4+) could win material via discovered attacks or forks.
- Lost material/king safety after allowing ...Qxh2+ then Bc4+ fork-style check winning material - failed to keep king safe after queen trade-off tactics around move 16-17.
- General: When opponent's queen reaches a square like e6 deep in your position with a knight on g5, treat it as an immediate mating threat check, not just a positional annoyance - calculate forced lines before making any other move.
- General: Before playing ...hxg5-type pawn captures near your own king, check if it opens a file (h-file) directly into your king with no blocking pieces - count attackers vs defenders on that file first.

## Notes

Stockfish itself is GPL-3.0 software by the Stockfish developers (github.com/official-stockfish/Stockfish); this pack contains no engine code. The knowledge here is generated from live play and regenerates as more games are played: fetch `https://stockfish.finance/skill/stockfish-desk.zip` for the latest.