dice-check

name	dice-check
description	Resolve any check, save, attack, or world-roll using the dice-roller MCP — never compute dice results from LLM memory.
version	0.1.0
author	dobry-ops
license	MIT
metadata	{"hermes":{"tags":["koth-dm","dice","resolution"],"category":"campaign-management","related_skills":["roll-initiative","koth-dm-journal"],"config":{"destructive":false}}}

dice-check

Use the dice-roller MCP for every roll the GM (you) needs to make. Players roll their own dice and report results. The GM rolls for: NPCs, the world, weather, random tables, and anything else the players don't roll for.

Hard rule

Never compute a dice result from memory. LLM dice math drifts toward middle-of-the-range averages — random feeling is preserved but actual randomness is not. Every roll goes through dice_roller.roll(expr).

Expression cheatsheet

Expression	Meaning
1d20+5	One d20 plus modifier 5 (standard check / save / attack)
2d6+3	PbtA-style 2d6 + modifier (the campaign's hard-rule mechanic)
4d6kh3	4d6, keep highest 3 (D&D 5e ability score generation)
2d20kh1	2d20 keep highest (advantage)
2d20kl1	2d20 keep lowest (disadvantage)
1d100	Percentile roll for random tables
1d6-1	One d6 minus 1 (e.g., poison damage with a negative mod)

Combine freely: 2d6+1d4+3, etc.

When the GM rolls

• NPC attacks / saves / checks — roll them, report the breakdown if it matters to the fiction ("the goon's blade misses by 2 — the parry is just in time").
• Random world events — the storm intensifies? Roll for it. Hostage morale? Roll. The cap-point ticks? Roll.
• PbtA resolution — when a player's action calls for the 2d6+mod hard rule from CAMPAIGN.md, ASK the player to roll 2d6+<their_mod>. You do NOT roll for them. The result they report drives the resolution: 10+ clean, 7–9 mixed, 6– complication.

What players roll

When a player needs to roll, ASK in plain English with the check type, and offer both options:

"Bovf, this is a Brawn check — roll 2d6+Brawn yourself, or say roll for me and I'll roll it on the table."

Path A — player rolls and reports

Take the number at face value. Don't second-guess. Examples of valid reports: "I got 9", "rolled 4 and 3 plus 2 = 9", "7". Arbitrate the outcome.

Path B — player asks YOU to roll ("roll", "Roll", "roll for me", "you

roll", "I don't have dice")

Use the character-sheets MCP to compose the expression, then roll. The exact sequence — do this every time a player asks you to roll a check:

1. Call character_sheets.get_character(player='<their mxid>') to fetch their sheet.

2. Read the relevant stat (stats.brawn, stats.cunning).

3. Compose the expression: f"2d6+{stat}" (e.g. "2d6+2").

4. Call dice_roller.roll(expression).

5. Report the breakdown out loud and arbitrate the outcome:

   "Rolling Cunning for you (Bovf, +2) — 2d6+2 → [4, 3]+2 = 9. Mixed success."

When the sheet lookup fails (no PC yet, e.g. solo test)

If get_character raises "no character for player …", the player has no sheet yet. Two graceful options:

• Ask them inline: "What's your Cunning mod for this one?" Then dice_roller.roll(f"2d6+{value}") with what they tell you.
• Suggest setup: "You don't have a sheet yet — say start campaign if you want session zero, or just tell me the mod and I'll roll."

Do NOT default to a +0 silently. Always confirm or ask.

Hard invariants

• Both paths are equally valid. The matrix-only campaign cadence means some players never have physical dice — refusing on principle breaks the game.
• Never compute dice in your head. Player-rolled-and-reported OR you-rolled-via-MCP OR you-rolled-for-NPCs — every roll has honest randomness behind it.
• Always use the live sheet for stats. Don't trust the player's recall of their own stats during a check; the sheet is canon. If they disagree, pause and reconcile (probably via update_character).

Reporting GM rolls

When YOU roll, include the expression and the result so the table can audit:

"The goon swings — 1d20+4 → 17. Hit. Damage 1d8+2 → 6."

This keeps the roll honest and visible, even though the actual randomness comes from the MCP.

Related: roll-initiative opens combat; koth-dm-journal logs outcomes.