/**
 * OpenAI Chat Completions wire shapes, as Databricks Model Serving speaks them.
 *
 * These are the request/reply payload types for `/chat/completions` and a
 * serving endpoint's `invocations` URL. They are deliberately declared here
 * rather than imported from the OpenAI or AI SDK packages: both keep these
 * fields under internal namespaces that are not part of their public API,
 * whereas the wire payload itself is the stable contract every caller in this
 * repo actually codes against.
 *
 * @module
 */
import { z } from "zod";
export declare const ChatRoleSchema: z.ZodEnum<{
    system: "system";
    developer: "developer";
    user: "user";
    assistant: "assistant";
    tool: "tool";
}>;
export type ChatRole = z.infer<typeof ChatRoleSchema>;
export declare const ChatContentPartSchema: z.ZodObject<{
    type: z.ZodOptional<z.ZodString>;
    text: z.ZodOptional<z.ZodString>;
}, z.core.$catchall<z.ZodUnknown>>;
export type ChatContentPart = z.infer<typeof ChatContentPartSchema>;
export declare const ChatToolCallFunctionSchema: z.ZodObject<{
    name: z.ZodString;
    arguments: z.ZodString;
}, z.core.$strip>;
export type ChatToolCallFunction = z.infer<typeof ChatToolCallFunctionSchema>;
export declare const ChatToolCallSchema: z.ZodObject<{
    id: z.ZodString;
    type: z.ZodString;
    function: z.ZodObject<{
        name: z.ZodString;
        arguments: z.ZodString;
    }, z.core.$strip>;
}, z.core.$strip>;
export type ChatToolCall = z.infer<typeof ChatToolCallSchema>;
export declare const ChatMessageSchema: z.ZodObject<{
    role: z.ZodString;
    content: z.ZodOptional<z.ZodNullable<z.ZodUnion<readonly [z.ZodString, z.ZodObject<{
        type: z.ZodOptional<z.ZodString>;
        text: z.ZodOptional<z.ZodString>;
    }, z.core.$catchall<z.ZodUnknown>>, z.ZodArray<z.ZodObject<{
        type: z.ZodOptional<z.ZodString>;
        text: z.ZodOptional<z.ZodString>;
    }, z.core.$catchall<z.ZodUnknown>>>]>>>;
    tool_calls: z.ZodOptional<z.ZodArray<z.ZodObject<{
        id: z.ZodString;
        type: z.ZodString;
        function: z.ZodObject<{
            name: z.ZodString;
            arguments: z.ZodString;
        }, z.core.$strip>;
    }, z.core.$strip>>>;
    tool_call_id: z.ZodOptional<z.ZodString>;
    name: z.ZodOptional<z.ZodString>;
}, z.core.$strip>;
export type ChatMessage = z.infer<typeof ChatMessageSchema>;
/**
 * Top-level request fields an OpenAI client may send that Databricks Model
 * Serving rejects outright, failing the whole turn rather than ignoring them.
 *
 * Databricks validates the chat body strictly, so an unrecognized key comes
 * back as `parallel_tool_calls: Extra inputs are not permitted` (the
 * gateway's pydantic validation) or `json: unknown field "parallel_tool_calls"`
 * (its strict JSON decode), depending on the endpoint. Everything listed here
 * is either OpenAI-platform bookkeeping with no bearing on the completion, or -
 * in the case of `parallel_tool_calls` - a real setting Databricks has no way
 * to accept, so dropping it is the only way the request can succeed at all.
 *
 * Callers that translate a request field-by-field through an allowlist never
 * need this; it exists for the
 * paths that forward a client body largely as-is.
 */
export declare const UNSUPPORTED_CHAT_FIELDS: readonly string[];
/**
 * Delete the fields Databricks rejects from a chat request body, in place.
 * Returns the names actually removed so a caller can log what it dropped.
 *
 * @param body - Parsed chat request body. Mutated.
 * @param extra - Additional field names to drop, for a workspace or endpoint
 *   that rejects something not yet in {@link UNSUPPORTED_CHAT_FIELDS}.
 */
export declare function stripUnsupportedChatFields(body: Record<string, unknown>, extra?: readonly string[]): string[];
export declare const ChatContentToTextOptionsSchema: z.ZodObject<{
    separator: z.ZodOptional<z.ZodString>;
    types: z.ZodOptional<z.ZodArray<z.ZodString>>;
}, z.core.$strip>;
export type ChatContentToTextOptions = z.infer<typeof ChatContentToTextOptionsSchema>;
/**
 * Normalize structured chat content to an array. Providers usually emit a
 * parts array, but some compatibility layers collapse a one-part array to the
 * object itself. Returns `undefined` for strings, nulls, and other scalar
 * values so callers can distinguish structured content from plain text.
 */
export declare function chatContentParts(content: unknown): ChatContentPart[] | undefined;
/**
 * Flatten a message `content` value to plain text. Accepts the string form and
 * structured content as either one {@link ChatContentPart} or an array, and
 * yields `""` for anything else (null, a lone image part, a malformed payload).
 * Typed as `unknown` because most callers are reading a just-parsed JSON body,
 * and the point of this helper is that they do not have to pre-check it.
 */
export declare function chatContentToText(content: unknown, options?: ChatContentToTextOptions): string;