import type { ProviderMessage } from "./types.js";
import type { BaseMessage } from "../agents/types.js";
/** Attachment accepted by {@link convertMessagesToProvider}. */
export interface InspectorAttachment {
    /** Attachment kind. Files that are not images are ignored. */
    type: "image" | "file";
    /** Base64-encoded attachment bytes. */
    data: string;
    /** MIME type for the encoded bytes. */
    mimeType: string;
}
/** Text or completed tool invocation in an inspector message. */
export interface InspectorMessagePart {
    /** Message part kind. */
    type: "text" | "tool-invocation";
    /** Text content when `type` is `"text"`. */
    text?: string;
    /** Invocation details when `type` is `"tool-invocation"`. */
    toolInvocation?: {
        /** Tool name. */
        toolName: string;
        /** Tool arguments. */
        args: Record<string, unknown>;
        /** Completed result. Omit while the invocation is pending. */
        result?: unknown;
    };
}
/** Structural inspector message accepted by {@link convertMessagesToProvider}. */
export interface InspectorMessageLike {
    /** Author of the message. */
    role: "user" | "assistant";
    /** Plain text or framework-specific content. */
    content: unknown;
    /** Optional message attachments. */
    attachments?: InspectorAttachment[];
    /** Optional AI SDK-style message parts. */
    parts?: InspectorMessagePart[];
}
/**
 * Converts LangChain messages into provider-neutral history.
 *
 * @param messages - LangChain history in conversation order.
 * @returns Equivalent provider messages.
 * @throws TypeError if a message has an unsupported or unknown role.
 */
export declare function convertExternalHistoryToProvider(messages: BaseMessage[]): ProviderMessage[];
/**
 * Convert inspector chat `Message[]` to provider-neutral `ProviderMessage[]`.
 *
 * Assistant messages with completed tool invocations are expanded into an
 * assistant message (bearing `toolCalls`) followed by one `tool` message per
 * invocation carrying the serialized result. This mirrors what the inspector
 * previously built using LangChain's AIMessage + ToolMessage pair.
 *
 * @param messages - Inspector messages in conversation order.
 * @returns Provider-neutral messages, including completed tool call/result
 * pairs.
 */
export declare function convertMessagesToProvider(messages: InspectorMessageLike[]): ProviderMessage[];
/**
 * Extract the top-level `system` instruction (if any) from a ProviderMessage
 * list and return both the system text and the messages without it.
 *
 * Anthropic and Google do not accept a `system` role inside their `messages`
 * array; they take it as a top-level field instead.
 */
export declare function extractSystem(messages: ProviderMessage[]): {
    system?: string;
    rest: ProviderMessage[];
};
/**
 * Parses a base64 data URL.
 *
 * @param url - URL in `data:<mime>;base64,<payload>` form.
 * @returns The MIME type and base64 payload, or `null` for another URL form.
 */
export declare function parseDataUrl(url: string): {
    mimeType: string;
    data: string;
} | null;
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