Read your token receipts right: volume and cost are different leaderboards

The Stack

Steps

1. 1

   Attribute usage by tokens and cost, and check the flip

   List each model with its tier, its token count, and its output price per million tokens. CI computes each tier's share of volume and share of cost and confirms the flip: cheap open dominates volume, premium dominates cost. Deciding what to route where is fenced.

   cat > receipts.json <<'JSON'
   {
     "period": "2026-06",
     "models": [
       { "name": "DeepSeek V4 Flash", "tier": "cheap_open", "tokens": 167000000000, "usd_per_mtok": 0.28 },
       { "name": "GLM 5.2", "tier": "cheap_open", "tokens": 50200000000, "usd_per_mtok": 3.00 },
       { "name": "Claude Opus 4.8", "tier": "premium", "tokens": 14800000000, "usd_per_mtok": 25.00 }
     ]
   }
   JSON
   node -e '
   const fs = require("fs");
   const c = JSON.parse(fs.readFileSync("receipts.json", "utf8"));
   function bad(m) { console.error("BAD: " + m); process.exit(1); }
   const models = c.models || [];
   if (models.length < 2) bad("need at least two models to compare");
   let totTok = 0, totCost = 0;
   const tierTok = {}, tierCost = {};
   for (const m of models) {
     if (!m.tier || m.tokens == null || m.usd_per_mtok == null) bad("each model needs tier, tokens, usd_per_mtok");
     const cost = (m.tokens / 1e6) * m.usd_per_mtok;
     totTok += m.tokens; totCost += cost;
     tierTok[m.tier] = (tierTok[m.tier] || 0) + m.tokens;
     tierCost[m.tier] = (tierCost[m.tier] || 0) + cost;
   }
   function pct(x, t) { return (x / t * 100).toFixed(1); }
   const coVol = tierTok.cheap_open || 0, coCost = tierCost.cheap_open || 0;
   const prVol = tierTok.premium || 0, prCost = tierCost.premium || 0;
   if (!(coVol > totTok / 2)) bad("cheap_open should dominate volume for this pattern");
   if (!(prCost / totCost > prVol / totTok)) bad("premium cost-share should exceed its volume-share (the flip)");
   console.log("receipts OK: cheap_open is " + pct(coVol, totTok) + "% of volume but " + pct(coCost, totCost) + "% of cost; premium is " + pct(prVol, totTok) + "% of volume but " + pct(prCost, totCost) + "% of cost (volume != value)");
   '

2. 2

   Act on the split (the routing step, not checked by CI)

   Once you can see that cheap open models carry your volume and a premium model carries your spend, route deliberately: bulk loops to the cheap open model, the fewer hard calls to premium. The actual routing and quality tradeoffs are fenced.