/**
 * How the runtime reacts when a request asks for something the target model does not declare.
 *
 * - `strict` throws a `NexusCapabilityError` before the provider is called.
 * - `warn` removes the option, records a `CapabilityWarning`, and continues.
 * - `off` sends the request unchanged, so a provider feature that is newer than the bundled
 *   registry is never blocked by stale metadata.
 *
 * An option the model does not mention at all is always allowed: absence means unknown, not
 * unsupported. Only an explicit `false`, or a value outside a declared constraint, is refused.
 */
export type CapabilityPolicy = 'strict' | 'warn' | 'off';
/** What happened to a requested option that the model could not honor as written. */
export type CapabilityWarningAction = 'dropped' | 'adjusted';
/**
 * A request option that was dropped or adjusted because the model does not support it as written.
 */
export interface CapabilityWarning {
    /** Dotted request path, such as `reasoning.effort` or `cache.mode`. */
    feature: string;
    /** The model it was requested for. */
    model: string;
    /** The provider, when known. */
    provider?: string;
    /** The value requested. */
    requested?: unknown;
    /** Whether it was dropped or adjusted. */
    action: CapabilityWarningAction;
    /** Value actually sent, when the option was clamped rather than removed. */
    adjustedTo?: unknown;
    /** Why. */
    reason: string;
}
/** How capability negotiation behaves. */
export interface CapabilityConfig {
    /** Default policy for every operation. Defaults to `warn`. */
    policy?: CapabilityPolicy;
    /**
     * Emit a one-time console warning the first time a deprecated or floating alias resolves.
     * Off by default so libraries do not write to a host application's logs uninvited.
     */
    warnOnAliasStage?: boolean;
}