/**
 * LlmMeteringPlugin
 *
 * Opt-in billing integration for graphile-llm. Completely separate from the
 * pure LLM plugins (text-search, text-mutation, rag).
 *
 * **How it works:**
 * 1. At schema build time, replaces `build.llmEmbedder` with a metered wrapper
 *    that has the same `(text: string) => Promise<number[]>` signature
 * 2. At request time, wraps every root query/mutation resolver to set up a
 *    request-scoped MeteringContext via AsyncLocalStorage
 * 3. When the embedder is called (by any plugin), the wrapper checks
 *    AsyncLocalStorage for a metering context and if found, calls
 *    check_billing_quota before and record_usage after
 * 4. If quota is exceeded, the wrapper returns null — the calling plugin sees
 *    null and handles it (search falls back to text-only, mutations throw)
 *
 * The pure plugins never import metering, config-cache, or billing types.
 * They call the embedder and handle null results — that's it.
 *
 * **Entity ID resolution:**
 * The billing `entity_id` is resolved via a configurable callback.
 * Default: reads `jwt.claims.user_id` from pgSettings. Override via
 * `metering.resolveEntityId` in GraphileLlmPreset options.
 *
 * **Graceful behavior:**
 * - billing_module not provisioned → embedder passes through unmetered
 * - entity_id not available → embedder passes through unmetered
 * - check_billing_quota throws → call is allowed (billing is opt-in)
 * - record_usage throws → call succeeds, recording silently skipped
 * - quota exceeded → embedder returns null
 */
import type { GraphileConfig } from 'graphile-config';
import type { MeteringConfig } from '../types';
declare global {
    namespace GraphileConfig {
        interface Plugins {
            LlmMeteringPlugin: true;
        }
    }
}
export declare function createLlmMeteringPlugin(meteringConfig?: MeteringConfig): GraphileConfig.Plugin;