Limits

All of these are exported constants, and the notation refuses anything past them by name.

Limit	Value	Constant
Dice in one roll	1 to 10	MIN_DICE, MAX_DICE
Dice in one roll, asked for from code	up to 100, all plain	MAX_DICE_BY_CODE
Sides of dice that all differ	100	MAX_UNIQUE_SIDES
A number in a formula	9999	MAX_MATH_NUMBER
The span of a formula's totals	1,000,000	MAX_MATH_TOTALS
Kinds of dice in one roll	4	MAX_GROUPS
Rerolls until clear, for each die	10	MAX_REROLLS
Faces of a custom die	2 to 20	MAX_FACES
Characters in a custom face	16	MAX_LABEL
A custom face's value	−9999 to 9999	MAX_FACE_VALUE
A loaded die	up to 100 sides, weights 0 to 99	MAX_LOADED_SIDES, MAX_WEIGHT
Sets kept on a device	50, names up to 40 characters	MAX_SETS, MAX_SET_NAME
Sides of a die	2 to 1000, or F	MIN_SIDES, MAX_SIDES
Bonus	−99 to +99	MAX_MODIFIER
Explosions for each die	10 more dice	MAX_EXPLOSIONS
Largest die that may explode	d100	MAX_EXPLODING_SIDES
Times a roll is thrown in one go	1 to 100 (1 to 10 in the tray)	MAX_TIMES
A roll's label	40 characters	MAX_ROLL_LABEL
Rolls kept in a history	500	HISTORY_LIMIT
Length of notation read	400 characters

More than ten dice

The tray and typed notation stop at ten dice: that is what fits a felt, and what a table throws. Code may ask for up to a hundred:

const volley = parseNotation("40d6", { maxDice: 100 })!;         // null without the option
normalizeSpec({ count: 40, sides: 6 }, { maxDice: 100 }).count;  // 40; 10 without it
roll(volley, seededSource("table"), { maxDice: 100 }).faces.length;  // 40; 10 without it
expectedTotal(volley);            // 140
chanceAtLeast(volley, 150);       // 0.1902
exactCounts(volley)!.outcomes;    // 6 to the 40th, a whole number of 32 digits

The one option, maxDice, is the same on all three, and on rollMany. Each stops at ten without it, as it always has: roll({ count: 50, sides: 6 }) throws ten dice. roll's third argument is the time of the roll, as before, or { at, maxDice }. On the command line it is --max-dice 100.

Past ten, every kind has to be plain dice: fair numbered or Fate dice, all added or one kept (100d20kh1), which is where the odds stay exact and quick however many there are. Anything else past ten is refused by name.