import { type ChatUiMessage, type ProviderModelMessage } from "./types.js";
/** Tunable limits used while preparing chat history for model context. */
export type MessagePrepLimits = {
    charsPerToken: number;
    historicalToolOutputMaskChars: number;
    historicalToolInputMaskChars: number;
    retainedMetadataStringMaxChars: number;
    retainedMetadataArrayMaxItems: number;
    retainedMetadataObjectMaxEntries: number;
};
/** Default limits for chat history preparation. */
export declare const DEFAULT_MESSAGE_PREP_LIMITS: MessagePrepLimits;
/** Field selector retained in a historical tool-input summary. */
export type HistoricalToolInputRetainedField = string | {
    inputName: string;
    outputName?: string;
} | {
    inputNames: readonly string[];
    outputName: string;
};
/** Policy for compacting a completed historical tool-call input. */
export type HistoricalToolInputRetentionPolicy = {
    compactCompletedInput: boolean;
    compactAfterChars?: number;
    retainInputFields?: readonly HistoricalToolInputRetainedField[];
};
/** Resolves the retention policy for a completed historical tool input. */
export type HistoricalToolInputRetentionPolicyResolver = (toolName: string, input: Record<string, unknown>) => HistoricalToolInputRetentionPolicy | null | undefined;
/** Diagnostic emitted when a completed historical tool input is compacted. */
export type HistoricalToolInputCompactionDiagnostic = {
    source: "provider" | "ui";
    toolName: string;
    toolCallId: string;
    originalInputChars: number;
    retainedInputChars: number;
    originalInputTokens: number;
    retainedInputTokens: number;
    originalInputHash: string;
    reason: "completed_historical_tool_input";
};
/** Options for historical tool-input compaction. */
export type HistoricalToolInputRetentionOptions = {
    resolvePolicy?: HistoricalToolInputRetentionPolicyResolver;
    diagnostics?: HistoricalToolInputCompactionDiagnostic[];
    limits?: Partial<MessagePrepLimits>;
};
/** Options accepted by prepare provider model messages from UI messages. */
export interface PrepareProviderModelMessagesFromUiMessagesOptions {
    providerOwnedToolNames?: readonly string[];
    historicalToolInputRetention?: HistoricalToolInputRetentionOptions;
}
/** Estimate tokens. */
export declare function estimateTokens(value: unknown): number;
/** Approximate token categories for context diagnostics. */
export type MessageTokenBreakdown = {
    totalTokens: number;
    systemTextTokens: number;
    userContentTokens: number;
    assistantContentTokens: number;
    reasoningTokens: number;
    toolCallInputTokens: number;
    toolResultOutputTokens: number;
    fileTokens: number;
    unknownTokens: number;
};
/** Estimate token categories for provider, UI, or runtime messages. */
export declare function estimateMessageTokenBreakdown(messages: readonly unknown[]): MessageTokenBreakdown;
/** Compress turn. */
export declare function compressTurn(messages: ProviderModelMessage[], startIdx: number, endIdx: number): ProviderModelMessage[];
/** Enforce token budget with turn compression. */
export declare function enforceTokenBudgetWithTurnCompression(messages: ProviderModelMessage[], budget: number, overhead: number): ProviderModelMessage[];
/** Check whether the model supports the file media type. */
export declare function isModelSupportedFileMediaType(mediaType: string): boolean;
/** Normalizes message file part media types. */
export declare function normalizeMessageFilePartMediaTypes(messages: ChatUiMessage[]): ChatUiMessage[];
/** Rewrite unsupported file parts as annotations. */
export declare function rewriteUnsupportedFilePartsAsAnnotations(messages: ChatUiMessage[]): ChatUiMessage[];
/** Strip pending tool parts. */
export declare function stripPendingToolParts(messages: ChatUiMessage[]): ChatUiMessage[];
/** Sanitize provider model messages. */
export declare function sanitizeProviderModelMessages(messages: ProviderModelMessage[]): ProviderModelMessage[];
/** Prepare provider model messages from UI messages. */
export declare function prepareProviderModelMessagesFromUiMessages(messages: ChatUiMessage[], options?: PrepareProviderModelMessagesFromUiMessagesOptions): ProviderModelMessage[];
/** Mask old tool outputs. */
export declare function maskOldToolOutputs(messages: ProviderModelMessage[]): ProviderModelMessage[];
/** Compact large historical tool-call inputs after matching results are available. */
export declare function compactOldToolInputs(messages: ProviderModelMessage[], options?: HistoricalToolInputRetentionOptions): ProviderModelMessage[];
/** Compact large historical UI-message tool inputs after matching results are available. */
export declare function compactHistoricalUiMessageToolInputs(messages: ChatUiMessage[], options?: HistoricalToolInputRetentionOptions): ChatUiMessage[];
/** Repair tool pairs. */
export declare function repairToolPairs(messages: ProviderModelMessage[]): ProviderModelMessage[];
/** Estimate overhead. */
export declare function estimateOverhead(instructions: unknown, toolCount: number): number;
/** Ensure tool call inputs helper. */
export declare function ensureToolCallInputs(messages: ProviderModelMessage[]): ProviderModelMessage[];
/** Compact for step. */
export declare function compactForStep(messages: ProviderModelMessage[], overhead?: number, options?: {
    historicalToolInputRetention?: HistoricalToolInputRetentionOptions;
}): ProviderModelMessage[];
/** Dedupe tool history. */
export declare function dedupeToolHistory(messages: ProviderModelMessage[]): ProviderModelMessage[];
/** Enforce token budget. */
export declare function enforceTokenBudget(messages: ProviderModelMessage[], budget?: number, overhead?: number): ProviderModelMessage[];
//# sourceMappingURL=message-prep.d.ts.map