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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228import { type LanguageModel, wrapLanguageModel } from "ai";import { policyFor, type Role } from "./auth";import { getCatalog, getRegistry } from "./inference";import type { Store, UsageEntry } from "./store";
/** * What a run costs, and who may keep spending. * * Two halves of one idea. The ledger records every provider call with a price * attached, and a budget reads that ledger back to decide whether a role has * spent enough for one day. Both hang off `payer`: a call on someone's own * connected account is recorded but never counted against a budget, because a * budget bounds what the operator pays for and nothing else. * * Metering happens at the model, not at the turn. A turn with three tool steps * is three calls, a research run is a lead plus its workers, and a title is a * fourth model nobody picked — measuring at the model catches all of it, where * measuring at the turn would quietly miss most of what a busy run spends. */
/** The rolling window a budget is measured over. Not a calendar day: no timezone to argue with. */export const DAY_MS = 86_400_000;
const num = (n: unknown): number => (typeof n === "number" && Number.isFinite(n) ? n : 0);
/** Per-million prices for a ref, from wherever the ref is known. */function priceOf(modelRef: string): { in: number; inCached: number; out: number } { const [providerId, ...rest] = modelRef.split("/"); const modelId = rest.join("/"); try { const enabled = getRegistry() .listModels() .find((m) => m.ref === modelRef); if (enabled) { // The registry's view carries no cached price; the catalog underneath // does, so fall through to it for that one number. const cached = getCatalog()?.getModel(providerId ?? "", modelId); return { in: num(enabled.costPer1MIn), inCached: num(cached?.costPer1MInCached), out: num(enabled.costPer1MOut), }; } } catch { // no registry yet (early boot, tests): the catalog below may still know it } const model = getCatalog() ?.getProvider(providerId ?? "") ?.models.find((m) => m.id === modelId); return { in: num(model?.costPer1MIn), inCached: num(model?.costPer1MInCached), out: num(model?.costPer1MOut), };}
/** * What a call cost, in dollars. * * Cache reads are charged at the cached rate only when the catalog names one. * A provider that reports a cache hit against a catalogue with no cached price * is charged the full rate instead of nothing: understating a number a budget * is measured against is the wrong way to be wrong. */export function costOf( modelRef: string, inputTokens: number, outputTokens: number, cachedInputTokens = 0,): number { const price = priceOf(modelRef); const cachedRate = price.inCached > 0 ? price.inCached : price.in; return ( (inputTokens / 1e6) * price.in + (cachedInputTokens / 1e6) * cachedRate + (outputTokens / 1e6) * price.out );}
/** * The token counts on a response, whichever shape they arrive in. * * The SDK's current spec reports each figure as an object — `{total, noCache, * cacheRead}` for input, `{total, text, reasoning}` for output — where older * ones (and kloe's own echo model) report a plain number. Reading only the * number is how this shipped recording nothing at all: every real adapter sends * the object, and an object coerces to zero without complaining. */export function countUsage(usage: unknown): { input: number; cachedInput: number; output: number;} { const u = (usage ?? {}) as { inputTokens?: unknown; outputTokens?: unknown }; const inp = u.inputTokens as { total?: unknown; noCache?: unknown; cacheRead?: unknown }; const out = u.outputTokens as { total?: unknown }; if (typeof u.inputTokens === "number" || typeof u.outputTokens === "number") { return { input: num(u.inputTokens), cachedInput: 0, output: num(u.outputTokens) }; } const cached = num(inp?.cacheRead); // `noCache` when it's there, else back out the cache read from the total — // the two must not be added together, they overlap. const fresh = inp?.noCache !== undefined ? num(inp.noCache) : Math.max(0, num(inp?.total) - cached); return { input: fresh, cachedInput: cached, output: num(out?.total) };}
/** Who a call is billed to, and where to file it. */export interface Meter { store: Store; sub: string; payer: UsageEntry["payer"]; conversationId?: string;}
function record(meter: Meter, modelRef: string, usage: unknown): void { const { input, cachedInput, output } = countUsage(usage); // The provider told us nothing; there is nothing to file. if (input === 0 && cachedInput === 0 && output === 0) return; meter.store.recordUsage({ ts: Date.now(), sub: meter.sub, payer: meter.payer, service: "inference", providerId: modelRef.split("/")[0] ?? "", modelRef, conversationId: meter.conversationId, // The whole prompt, cache hits included — that is the number a person // recognizes. What each part cost is already settled in cost_usd. inputTokens: input + cachedInput, outputTokens: output, costUsd: costOf(modelRef, input, output, cachedInput), });}
/** * Wrap a model so every call it serves lands in the ledger. * * The stream case files its row when the stream drains rather than when the * `finish` part arrives, so a turn the user cancels mid-sentence still records * what it had spent by then — the provider charged for it either way. */export function metered(model: LanguageModel, modelRef: string, meter: Meter): LanguageModel { return wrapLanguageModel({ // `LanguageModel` includes the string form (a ref the SDK resolves itself); // everything kloe resolves is already an instance, and only an instance can // be wrapped. model: model as Exclude<LanguageModel, string>, middleware: { wrapGenerate: async ({ doGenerate }) => { const result = await doGenerate(); record(meter, modelRef, result.usage); return result; }, wrapStream: async ({ doStream }) => { const { stream, ...rest } = await doStream(); let usage: unknown; return { ...rest, stream: stream.pipeThrough( new TransformStream({ transform(chunk, controller) { const part = chunk as { type?: string; usage?: unknown }; if (part.type === "finish" && part.usage) usage = part.usage; controller.enqueue(chunk); }, flush() { record(meter, modelRef, usage); }, }), ), }; }, }, });}
/** What a role may spend of the instance's credits in a day. 0 means no bound. */export interface Budget { usdPerDay: number; tokensPerDay: number;}
export function budgetFor(role: Role): Budget { const policy = policyFor(role); return { usdPerDay: policy.usdPerDay, tokensPerDay: policy.tokensPerDay };}
export interface BudgetStatus { /** True when this person may still start work on the instance's credits. */ ok: boolean; /** Why not, in words a person can act on. */ reason?: string; spentUsd: number; spentTokens: number; budget: Budget; /** When the window rolls far enough for them to continue. */ resetsAt?: number;}
/** * Where this person stands against their role's budget. * * Checked when a run starts, not while it runs. A turn already in flight * finishes and is billed in full — stopping mid-sentence would waste what was * already spent to save the tail of one answer. */export function budgetStatus(store: Store, sub: string, role: Role): BudgetStatus { const budget = budgetFor(role); const since = Date.now() - DAY_MS; const spent = store.spentSince(sub, since); const out: BudgetStatus = { ok: true, spentUsd: spent.costUsd, spentTokens: spent.tokens, budget, }; if (budget.usdPerDay > 0 && spent.costUsd >= budget.usdPerDay) { out.ok = false; out.reason = `daily limit of $${budget.usdPerDay.toFixed(2)} reached`; } else if (budget.tokensPerDay > 0 && spent.tokens >= budget.tokensPerDay) { out.ok = false; out.reason = `daily limit of ${budget.tokensPerDay.toLocaleString("en-US")} tokens reached`; } if (!out.ok) out.resetsAt = since + DAY_MS; return out;}