import type { TSchema } from "typebox";
/** Port of 204 `Lqn` — derive the strict form of a whole schema (root must be `type:"object"`). */
export declare function deriveStrictSchema(schema: unknown): {
    ok: true;
    schema: Record<string, unknown>;
} | {
    ok: false;
    reason: string;
};
/** Exposed for callers that only need validity (no derivation). Runs the size guard first. */
export declare function validateJsonSchemaShape(schema: unknown): string | null;
export type CompiledOutputSchema = 
/** The schema is not a valid JSON Schema (or too large) — callers must FAIL FAST, never run silently. */
{
    error: string;
}
/** Strict derivation succeeded: `modelSchema` is the tightened form to hand the model. */
 | {
    modelSchema: TSchema;
    strict: true;
}
/** Valid but outside the strict subset: serve the schema as-is; `fallbackReason` is the observable why. */
 | {
    modelSchema: TSchema;
    strict: false;
    fallbackReason: string;
};
/**
 * Validate + strict-derive a structured-output schema (CC 2.1.205 semantics):
 *   invalid / oversized schema → `{error}` (the caller throws — no silent acceptance);
 *   in-subset schema → `{modelSchema: strictForm, strict:true}` (`additionalProperties:false` stamped);
 *   valid-but-unsupported schema → `{modelSchema: original, strict:false, fallbackReason}` (observable).
 * A derivation CRASH also falls back non-strict (CC's inner try/catch), never fails the task.
 */
export declare function compileOutputSchema(schema: TSchema): CompiledOutputSchema;