Dmcheck MCP server

dmcheck

Deterministic conduct verdicts for live tabletop sessions — CI for running a game.

Feed it a session transcript (and optionally an engine event ledger) plus a table charter, and it returns named findings — the player whose question was never answered, the dice roll nobody acknowledged, the turn that began without anyone being told, the spoiler that leaked into the channel, the five-minute dead air. Every finding cites the charter rule it violates, with the evidence attached.

Agents start here → SKILL.md — when to call this, worked examples, MUST/MUST NOTs. Family contract: FAMILY.md.

Cold-boot probe (2026-07-24): a fresh agent session given only this repo URL installed and refereed a session in 2 commands, verified all three exit-code legs against the docs, and confirmed the no-false-accusation contract held (a consumed roll produced silence). Its friction notes shipped as 0.1.1 (--dice-bot, dmcheck charter).

The design contract: a false accusation is the unforgivable bug. Only source-observed evidence becomes a definite finding. Legacy ambiguity is either silent or explicitly labeled severity: advisory, provenance: inferred, confidence: low; it is never promoted by R8 or sent to a notification hook. The verdict path is model-free and deterministic: same transcript, same findings, every time.

30 seconds to a refereed session

$ pip install dmcheck          # stdlib only, no dependencies
$ dmcheck run session.jsonl --gm "Greta"
{
 "result_schema_version": "1.0",
 "status": "findings",
 "exit_code": 1,
 "mode": "closed",
 "messages": 9,
 "findings": [
  {"finding_id": "r2-…", "rule": "R2", "summary": "unconsumed-roll: a dice result got no correlated GM narration within threshold",
   "charter": "roll_ack_within_messages=4; correlation=explicit",
   "detail": "dice result from DiceBot received no correlated GM narration within 4 messages",
   "evidence": {"index": 6, "author": "DiceBot", "obligation_id": "roll-42"},
   "status": "open", "severity": "finding", "provenance": "observed", "confidence": "high",
   "charter_digest": "sha256:...", "effective_policy": {"roll_ack_within_messages": 4, "...": "..."}},
  ...
 ],
 "counts": {"R1": 1, "R2": 1, "R6": 1, "R7": 1, "R8": 1}
}

Portfolio hosts that emit table-kit's versioned contract can use dmcheck run-events session-events.jsonl --gm "gm-dan" instead of pre-projecting a transcript. The strict adapter accepts a JSON array or JSONL of table.event/1.0 objects and preserves event/correlation IDs in finding evidence. A declared action is not treated as an authoritative engine resolution, so legal Reactions and interrupts are not falsely accused. Transport gaps, unknown versions/types, and zero-compatible streams return typed incomplete status and exit 2; malformed v1 events return invalid and exit 2. Redacted message content is likewise incomplete because absence of prose cannot prove absence of a conduct obligation. This unreleased adapter is pinned to table-kit PR #11 and does not imply host attestation.

Add --table-evaluation to run-events when a portfolio host needs the shared table.evaluation/1.0 envelope. The projection has deterministic evaluation identity, exact event evidence references, per-rule and aggregate coverage, cursor/input digest, public-policy digest, and status/exit-code mapping. It is always self_attested; dmcheck cannot confer host authority on its own output.

Shortened. The full README is on GitHub.