Chess Coach, play chess and learn every move
Chess Coach lets you play chess against the computer and learn from every move. After each move it gives your move a mark, such as ✓ Good or ? Mistake, says in one or two plain sentences why the computer played its reply, and shows the better move when you went wrong. At the end you get your accuracy, a count of good moves and errors, and the key moments of the game.
Chess Coach is one of the ZenithAI Agents. Open Agents in the top bar and choose Chess Coach under Learning. It runs completely on your organisation’s own ZenithAI server.
Start a game
Section titled “Start a game”- Open Agents, then Chess Coach. The start screen lists your Continue games (unfinished, with a Resume button) and your Recent games (finished, with a Review button).
- Click New game.
- Under Your colour, choose White, Random or Black. White moves first.
- Under Level, choose one:
- Moderate: makes human-like slips. Good for learning and for beginners. This is the default.
- Difficult: punishes mistakes. For players who already know the basics well.
- Click Start game. If you play Black, the computer makes the first move.
You can have up to 5 unfinished games at a time. To start a sixth, finish or delete one first.
Make a move
Section titled “Make a move”Use whichever way suits you:
| Way | How |
|---|---|
| Click | Click a piece, then the square to move it to. Dots show the squares it can legally go to |
| Drag | Drag the piece to its square. This also works with a finger on a phone or tablet |
| Keyboard | Move around the board with the arrow keys, press Enter or Space to pick up and put down, Esc to cancel |
| Type | Type the move in the box Type a move, e.g. Nf3 and press Play. Nf3, exd5, O-O and e8Q all work |
When a pawn reaches the last row, a Promote to picker lets you choose a queen, rook, bishop or knight.
If a move is not allowed, the board shakes and nothing changes. A typed move that fits two pieces asks you to
type it in full, for example Nbd7 instead of Nd7.
Flip turns the board around. The ⋯ More menu has Copy PGN, Download .pgn, Sounds on or off, and New game.
Read the coach notes
Section titled “Read the coach notes”Every move gets a card in the notes panel, titled Move 1, Move 2 and so on. The card says Checking… for a moment while the engine looks at the position, then Brief note. You never wait for the note to play your next move.
The computer’s move is explained in one sentence, for example The computer played Nd4 because it attacks two pieces at once. Other reasons include it gives check, it pins a piece and it puts the king to safety. When the computer itself slips (this happens at Moderate on purpose), the note says so and invites you to take advantage.
Your move gets a mark and a short reason:
| Mark | Meaning |
|---|---|
| ★ Best | The engine’s own top choice |
| ! Excellent | Almost as good as the best move |
| ✓ Good | A sound move that keeps your position |
| Book | A well-known opening move |
| Forced | The only legal move in the position |
| ?! Inaccuracy | Gives away a small part of your winning chances |
| ? Mistake | Gives away a clear part of your winning chances |
| ?? Blunder | Gives away a large part of your winning chances, often the game |
For an Inaccuracy, Mistake or Blunder, the card says what went wrong in plain words, such as it leaves your knight on f3 open to attack, it misses a forced checkmate or it loses material, and opens a box with three lines:
- You played: your move.
- Better was: the move the engine prefers.
- Line: up to 8 moves showing how the better move continues. Click Show on the board to see it. A teal arrow shows the better move and a red arrow shows the computer’s answer to your move.
Words about your advantage appear only when you really were ahead before the move: it gives up part of your advantage, it lets your advantage slip away or it throws away your advantage, depending on how much was lost. If the position was level, the note says the move makes your position worse; if you were already behind, makes your position harder.
The name of the opening you are playing appears at the top of the notes, and the Moves tab lists the whole game.
Hints, takebacks, draws and resigning
Section titled “Hints, takebacks, draws and resigning”| Button | What it does | Limit |
|---|---|---|
| Hint | Draws a teal arrow for the best move in the position | 3 per game at both levels |
| Takeback | Undoes your last move and the computer’s reply | Unlimited at Moderate, 3 per game at Difficult |
| Draw | Offers a draw. Becomes Claim draw when the rules let you claim one, for example after the same position three times or 50 moves without a capture or pawn move | The computer accepts an offer only from move 30, and only when the position is level |
| Resign | Ends the game as a loss, after you confirm Resign this game? | None |
Using any hint or takeback marks the game assisted. It still counts, and the summary shows the mark so you can tell assisted games from unaided ones. A game that reaches 400 half-moves ends as a draw at the move limit.
The end of the game
Section titled “The end of the game”When the game ends, the Game over summary shows:
- The result, such as You won by checkmate, Draw by repetition or You resigned, with the opening, the number of moves, the level and the assisted mark if used.
- Your accuracy from 0 to 100, and the computer’s accuracy at its limited strength. Each move scores 100 when it keeps all your winning chances and less the more it gives away; book moves are left out. The game figure weighs your worst moves more than a plain average, so one blunder shows.
- A tally of your Book, Best, Good, Inaccuracy, Mistake and Blunder moves.
- Key moments: up to the 5 biggest errors of the game, each with a small board.
- Copy PGN, Download .pgn, New game and Rematch.
PGN is the standard chess file format. A downloaded game is named chess-coach-<date>.pgn and opens in any chess
program or website.
Your games and your data
Section titled “Your games and your data”- Games and notes are stored on your organisation’s own ZenithAI server, in your own space. The chess engine runs on the same server. Nothing about your games is sent outside.
- Your newest 200 finished games are kept; older ones are removed first. Open one from Recent games to review it move by move.
- An unfinished game you have not touched for 30 days is closed.
- To delete an unfinished game, click its bin icon under Continue and confirm. This can’t be undone.
- Delete data in your account removes all your chess games and notes at once.
Phones and tablets
Section titled “Phones and tablets”Chess Coach works on phones and tablets. On a narrow or upright screen the board sits above the notes and takes the full width; the notes and move list scroll in their own box, so the board stays in view. On a wide screen the notes panel uses the extra width with larger text. You can drag pieces with your finger.
Messages you may see
Section titled “Messages you may see”| Message | What it means and what to do |
|---|---|
| You are playing very fast. Wait a few seconds and try again. | More than 40 moves in a minute. Wait a moment |
| You have too many unfinished games. Open or delete one first. | You already have 5 unfinished games |
| The chess engine is busy; trying again… | Many people are playing. Chess Coach retries by itself |
| The chess server is very busy right now. Please try again in a minute. | The retries did not get through. Wait a minute |
| Checking your moves is taking longer than usual. Press Try again. | The notes took more than 90 seconds. Press Try again |
| Your session has ended. Please sign in again, then press Try again. | Sign in again in another tab, then press Try again |
| This game changed in another window. It has been refreshed. | The same game is open in another tab. The board now shows the latest position |
| The chess engine is restarting. Your move was not played; try again in a moment. | Play the move again in a few seconds |
Limits
Section titled “Limits”| What | Limit |
|---|---|
| Levels | Moderate and Difficult |
| Unfinished games | 5 at a time |
| New games | 20 an hour |
| Moves | 40 a minute |
| Hints | 3 per game |
| Takebacks | Unlimited at Moderate, 3 per game at Difficult |
| Finished games kept | The newest 200 |
| Unfinished game closed after | 30 days without a move |
| Game length | 400 half-moves, then a draw |
Common questions
What is ZenithAI Chess Coach?
Chess Coach is a ZenithAI agent where you play chess against the computer at Moderate or Difficult level. After every move it marks your move, from Best to Blunder, explains why the computer played its reply, and shows a better move when you went wrong. Each game ends with your accuracy and key moments.
How strong is the computer in Chess Coach?
Moderate plays like a club player and makes human-like slips, so it suits beginners and casual players. Difficult plays like a strong club player and punishes mistakes. Both use a strong chess engine with its strength deliberately limited, running on your organisation's own ZenithAI server.
Who writes the coach notes in Chess Coach?
The notes are built from the chess engine's analysis of each position, with fixed sentence patterns filled in with the facts of that move, such as the piece left open to attack or the forced checkmate missed. Every note is checked against the position. No language model writes them today.
How many hints and takebacks do I get?
Three hints per game at either level. Takebacks are unlimited at Moderate and limited to three per game at Difficult. A takeback undoes your move and the computer's reply. Using any hint or takeback marks the game as assisted, so your accuracy is read in that light.
How is my accuracy worked out?
Each of your moves gets a score from 0 to 100 based on how much winning chance it gave away compared with the engine's best move. Opening book moves are left out. The game figure combines the average of all moves with a measure that weighs your worst moves more, so one blunder counts.
Can I save or share a Chess Coach game?
Yes. At the end of a game, or from the More menu during it, choose Copy PGN or Download .pgn. PGN is the standard chess file format, so you can open the game in any chess program or website to replay it.
Where are my chess games stored, and can I delete them?
On your organisation's own ZenithAI server, in your own space; nothing is sent outside. Your newest 200 finished games are kept. You can delete an unfinished game with its bin icon. Delete data in your account removes all your games and notes at once.
Why can't I see Chess Coach on the Agents page?
Chess Coach is switched on per server by the server team. If the Agents page has no Chess Coach tile under Learning, it is not on for your server yet, or your server has not been updated. Ask your administrator.