import { z } from "zod";
import { type CanonicalModelId, type ProviderId } from "./canonical-model.js";
/**
 * Policy order and semantics are versioned; the version string travels into
 * telemetry (LLM Provider Routing PRD §4.2) so a routing-behavior change is
 * distinguishable from a configuration change after the fact.
 */
export declare const ROUTE_POLICY_VERSION = "provider-router-v1";
export type RoutePolicyVersion = typeof ROUTE_POLICY_VERSION;
/**
 * `ordered` tries each listed provider in order, skipping unavailable or
 * incapable endpoints. `only` is a hard fence: the marked canonical model is
 * never attempted through another provider. A separately configured fallback
 * model still expands under its own policy (PRD §4.2).
 */
export declare const providerPolicySchema: z.ZodDiscriminatedUnion<[z.ZodReadonly<z.ZodObject<{
    mode: z.ZodLiteral<"ordered">;
    providers: z.ZodArray<z.core.$ZodBranded<z.ZodString, "ProviderId", "out">>;
}, z.core.$strict>>, z.ZodReadonly<z.ZodObject<{
    mode: z.ZodLiteral<"only">;
    provider: z.core.$ZodBranded<z.ZodString, "ProviderId", "out">;
}, z.core.$strict>>], "mode">;
export type ProviderPolicy = z.infer<typeof providerPolicySchema>;
/**
 * The checked-in route registry. It contains policy only — never endpoints,
 * deployment names, credentials, prices, quota, or tenant-specific values.
 *
 * Naming note: the PRD draft called the bound default `azureBoundDefault`.
 * The harness is provider-agnostic, so the registry generalizes it to
 * `boundDefault`, applied when the host reports at least one provider
 * binding for the model (see `resolveProviderPolicy`).
 */
export declare const modelRouteRegistrySchema: z.ZodReadonly<z.ZodObject<{
    version: z.ZodLiteral<"provider-router-v1">;
    /** Used when a model has no explicit policy and no provider binding. */
    unboundDefault: z.ZodDiscriminatedUnion<[z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"ordered">;
        providers: z.ZodArray<z.core.$ZodBranded<z.ZodString, "ProviderId", "out">>;
    }, z.core.$strict>>, z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"only">;
        provider: z.core.$ZodBranded<z.ZodString, "ProviderId", "out">;
    }, z.core.$strict>>], "mode">;
    /** Used when a model has no explicit policy but has ≥1 provider binding. */
    boundDefault: z.ZodDiscriminatedUnion<[z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"ordered">;
        providers: z.ZodArray<z.core.$ZodBranded<z.ZodString, "ProviderId", "out">>;
    }, z.core.$strict>>, z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"only">;
        provider: z.core.$ZodBranded<z.ZodString, "ProviderId", "out">;
    }, z.core.$strict>>], "mode">;
    /** Keys are canonical model ids; parsing rejects deployment names. */
    models: z.ZodRecord<z.core.$ZodBranded<z.ZodString, "CanonicalModelId", "out">, z.ZodDiscriminatedUnion<[z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"ordered">;
        providers: z.ZodArray<z.core.$ZodBranded<z.ZodString, "ProviderId", "out">>;
    }, z.core.$strict>>, z.ZodReadonly<z.ZodObject<{
        mode: z.ZodLiteral<"only">;
        provider: z.core.$ZodBranded<z.ZodString, "ProviderId", "out">;
    }, z.core.$strict>>], "mode">>;
}, z.core.$strict>>;
export type ModelRouteRegistry = z.infer<typeof modelRouteRegistrySchema>;
/**
 * Parse and freeze a checked-in registry object at module initialization.
 * `satisfies` on the literal is not a runtime-validation substitute
 * (PRD §4.2) — hosts must call this on their checked-in object.
 */
export declare function parseModelRouteRegistry(input: unknown): ModelRouteRegistry;
/**
 * Policy precedence (PRD §4.2): exact canonical-model entry, then the bound
 * default when the host reports a provider binding for this model, then the
 * unbound default. An explicit policy always wins — in particular, an
 * explicit single-provider model does not become bound-first merely because
 * a binding is later added.
 *
 * `boundProviders` is the host's report of which providers have an explicit
 * binding for this model (e.g. an Azure deployment mapping). A catch-all
 * transport that serves every model without per-model configuration should
 * not be reported as a binding.
 */
export declare function resolveProviderPolicy(registry: ModelRouteRegistry, model: CanonicalModelId, boundProviders: ReadonlySet<ProviderId>): ProviderPolicy;
/** The provider order a policy prescribes; `only` is a single-entry order. */
export declare function policyProviderOrder(policy: ProviderPolicy): readonly ProviderId[];