@conform-ed/pci-math-entry

The reference PCI for the conform-ed QTI stack: math entry with MathLive input and compute-engine checking. It exists to be a real, end-to-end example of what a PCI package looks like for consumers of @conform-ed/qti-react — interaction module, pure checker, and response-processing operator, each on its own subpath.

The response contract

The response of record is a PCI JSON record:

• expression — the learner's LaTeX, exactly as written. Always present.
• verdict — an advisory boolean computed client-side by the same checker the platform re-scores with. Present only when the item carries checker config (data-correct, optional data-mode, data-tolerance); a high-stakes delivery redacts those properties and the module degrades to expression-only. Unjudgeable input omits the verdict — never a guess.

Items score portably with plain QTI (qti-field-value over verdict); platforms holding the expression re-score it server-side for the authoritative result.

Subpaths

• . — checker, operator, module core (injectable input), type identifier.
• ./checker — the pure function only (compute-engine; no qti-react, no DOM).
• ./operator — org.conform-ed.mathEquivalent for QtiRuntimeConfig.customOperators.
• ./module — the browser-ready module (MathLive + compute-engine). Heavy by design; load it lazily (ADR-0007: descriptors eager, implementations lazy):

const { mathEntryModule } = await import("@conform-ed/pci-math-entry/module");
registry.registerModule("math-entry", mathEntryModule);

Checking modes

• equivalent (default) — symbolic equality, any mathematically equal form passes; optional absolute tolerance for float answers.
• literal — the written form matters (EqualComAss-style: \frac{2}{4} and 0.5 fail against \frac{1}{2}; reordered terms pass).

Server-side re-scoring

The checker is a pure function — no adapters, usable from any API:

import { checkMathExpression } from "@conform-ed/pci-math-entry/checker";

Bun.serve({
  port: 3000,
  fetch: async (request) => {
    const { expression, correct, mode, tolerance } = await request.json();
    const result = checkMathExpression(expression, correct, { mode, tolerance });

    return Response.json(result); // { verdict: boolean | null, reason? }
  },
});