NAGs
A NAG is a Numeric Annotation Glyph, introduced in the PGN standard to annotate chess games. It consists of a dollar sign $ followed by a number from 1-255, with 0 being reserved to indicate no NAG (helpful for programmers).
NAGs 1-9 annotate the move just played, and most have a symbol that can use be instead. Hence in a PGN, Bc6 $1 is the same as Bc6!.
| NAG | Meaning | Symbol |
|---|---|---|
| 1 | Sharp / Great | ! |
| 2 | Mistake | ? |
| 3 | Brilliant | !! |
| 4 | Blunder | ?? |
| 5 | Speculative | !? |
| 6 | Dubious / Inaccuracy | ?! |
| 7 | Forced move (all others lose quickly) | □ |
| 8 | Singular move (no reasonable alternatives) | |
| 9 | Worst move |
ChessTake uses NAGs 1-7 and define three extra for move accuracy indication:
- Best - the best move in the position (but not Sharp/Brilliant).
- Good - not the best move, but pretty good nonetheless.
- OK - an OK move. Not bad, not dubious.
In summary, NAGs in ChessTake are used according to the following symbols, colours and meanings:
