@pipeworx/dice-roller

Connect: https://pipeworx.io/mcp — every tool in the catalog, including @pipeworx/dice-roller’s. Install: one-click buttons

No MCP client? Skip the connection: POST https://gateway.pipeworx.io/v1/tools/search_packs {"query":"..."} to find a tool below, GET /v1/tools/<name> for its schema, POST the same URL with arguments for the data — see For AI agents.

Tools: 3

Tabletop dice, coin flips and exact dice odds with real, reproducible randomness: roll any standard dice notation (2d6+3, 4d6kh3, 2d20kl1, 3d6!, 4dF, d%), flip up to 1,000 coins, or get the full probability distribution of a roll.

Tools

• roll_dice(notation, times?, seed?) — rolls the notation and returns every die, which dice were kept, per-term subtotals, the total and a readable breakdown. times (up to 100) repeats the roll and adds min/max/mean across repeats. Answers “roll 4d6 drop the lowest”, “roll with advantage”, “roll 2d6+3 six times”.
• flip_coins(count?, seed?) — flips up to 1,000 fair coins; returns the H/T sequence, heads and tails counts and the longest run.
• dice_odds(notation, target?, comparison?, seed?) — min, max, mean, standard deviation, mode, median and the probability of every total; with target, the chance the total is >= (default), >, <=, < or == it. Exact by enumeration for plain sums and for keep/drop pools up to 1,000,000 outcomes; otherwise (and always for exploding dice) a Monte Carlo estimate labelled method: "monte_carlo" with its sample count. Answers “what are the odds of 15+ on 3d6”, “how much does advantage help against DC 15”.

Every response carries seed and a meta envelope (seed, procedure, deck, source). Omit seed for a fresh random result; pass the returned seed back with the same arguments to reproduce it exactly. Results are random outcomes, not advice; the calling agent decides what they mean.

Notation

NdS terms joined by + or -, with whole-number constants (1d20+5, 2d6+1d4-1). N defaults to 1. S is a number, % (= 100) or F (fudge/Fate: -1, 0, +1). Modifiers go after the die, in this order: ! (exploding: a max face rolls another die), then kh/kl/dh/dl with an optional count (keep highest, keep lowest, drop highest, drop lowest; k alone means kh1). Limits: 1,000 dice per notation, 10,000 sides per die, 100 extra dice per exploding chain. Anything malformed or over a limit is refused with the reason and the grammar.

Auth

Keyless. No upstream, no outbound calls.

Data sources

• Pipeworx dice engine v1 (the shared chance engine in this repo): an sfc32 pseudo-random generator seeded from a cyrb128 hash of the seed string. A call without a seed takes a 128-bit seed from the platform’s cryptographic random source and returns it. Dice faces are drawn by rejection sampling, so no face is favoured at any die size.

The generated sequence for a given seed is pinned by a unit test. If a change to the engine re-deals seeded results, that test goes red, because people may have cited them.

Tools

• roll_dice — Pipeworx dice engine: roll tabletop dice notation with real randomness — NdS terms joined by + or - (2d6+1d4+3, 1d20-2), keep/drop (4d6kh3, 2d20kl1 for disadvantage, 4d6dl1), exploding dice (3d6!), fu
• flip_coins — Pipeworx dice engine: flip fair coins with real randomness — up to 1,000 per call. Returns the sequence (H/T), heads and tails counts, and the longest run. Omit seed for fresh flips; pass the return
• dice_odds — Pipeworx dice engine: the probability distribution of a dice notation (same grammar as roll_dice: 2d6+3, 4d6kh3, 2d20kl1, 4dF, 3d6!) — min, max, mean, standard deviation, mode, the probability of ever