Countwerk Pricing Runtime v2

Helper for the PriceCalc Runtime Contract (Dimensions -> Credits).

Install

npm i @sebastianmaierofficial/countwerk-pricing

Quickstart

import { loadProfileVersion } from "@sebastianmaierofficial/countwerk-pricing";

const engine = loadProfileVersion(profileVersionJson);

const input = {
  dimensions: {
    active_user_day: 1
  },
  attributes: {
    plan: "pro"
  }
};

const result = engine.price(input);

const auditPayload = engine.buildAuditPayload(input, result);

console.log(result.totalCredits);

// Optional: rounded credits for display-only convenience
const rounded = engine.price(input, { includeRounded: true, roundingMode: "ceil" });
console.log(rounded.totalCreditsToDeduct);

API

• loadProfileVersion(json) -> PricingEngine
• price(profileVersion, input) -> PriceResult
• buildAuditPayload(profileVersion, input, result) -> object
• PricingError (thrown in STRICT mode when unmatched dimensions are detected)

Notes

• Rule matching: AND across keys; array values are OR within a key; missing attribute means no match.
• Tie-breaker: priority DESC -> createdAt DESC -> ruleId ASC.
• rulesetHash: SHA-256 of normalized active rules (deterministically sorted).
• Quarantine: mode: "STRICT" throws PricingError with code = "UNMATCHED_DIMENSION". mode: "RUNTIME" returns unmatchedDimensions in the result.
• rulesetHash is validated against the computed hash when provided in the profile JSON.
• mode: "STRICT" throws PricingError with code = "RULESET_HASH_MISMATCH".
• mode: "RUNTIME" returns quarantineReason = "RULESET_HASH_MISMATCH".
• Countwerk deducts fractional credits. totalCredits is the raw fractional value.

Canonical v1 Schema (short)

ProfileVersion:

• profileVersionId, eurPerCredit, rateRules, rulesetHash, engineVersion

Rule:

• id, dimensionKey, creditsPerUnit, costPerUnitEur?, attributesMatch?, priority?, status?, createdAt?

Input:

• dimensions, attributes, mode?

Output:

• totalCredits, ruleIdsUsed, rulesetHash, profileVersionId, profileEngineVersion, runtimeEngineVersion, unmatchedDimensions?, quarantineReason?, breakdown?
• breakdown entries: { dimensionKey, qty, creditsPerUnit, credits, costPerUnitEur?, costEur?, ruleId }

Examples

CoachWunder: active_user_day (credits-only)

const profileVersionJson = {
  profileVersionId: "pv_2026_01_31",
  engineVersion: "pricecalc-v2",
  eurPerCredit: 0.01,
  rateRules: [
    {
      id: "rule_active_user_day_default",
      dimensionKey: "active_user_day",
      creditsPerUnit: 3,
      status: "active"
    }
  ]
};

const engine = loadProfileVersion(profileVersionJson);
const result = engine.price({
  dimensions: { active_user_day: 1 }
});

console.log(result.totalCredits); // 3

Petra: token pricing (credits per token)

const profileVersionJson = {
  profileVersionId: "pv_petra_2026_01_31",
  engineVersion: "pricecalc-v2",
  eurPerCredit: 0.01,
  rateRules: [
    {
      id: "rule_input_tokens",
      dimensionKey: "llm_input_tokens",
      creditsPerUnit: 0.0002,
      costPerUnitEur: 0.0000003,
      attributesMatch: { model: "gpt-4o-mini" },
      priority: 10,
      status: "active"
    },
    {
      id: "rule_output_tokens",
      dimensionKey: "llm_output_tokens",
      creditsPerUnit: 0.0006,
      costPerUnitEur: 0.0000012,
      attributesMatch: { model: "gpt-4o-mini" },
      priority: 10,
      status: "active"
    }
  ]
};

const engine = loadProfileVersion(profileVersionJson);
const result = engine.price({
  dimensions: { llm_input_tokens: 1200, llm_output_tokens: 350 },
  attributes: { model: "gpt-4o-mini" }
});

console.log(result.totalCredits);