import type { Api, Model, ToolChoice, ToolChoiceCompat, ToolChoiceSupport, ToolChoiceSupportSource } from "../types";
/**
 * Claude Mythos accepts tools but rejects forced tool use (Anthropic 400:
 * "tool_choice forces tool use is not compatible with this model"). Catalog
 * generation and dynamic discovery use this to default `toolChoiceSupport`.
 */
export declare function isClaudeForcedToolChoiceIncapableModelId(modelId: string): boolean;
/** Derives the effective static tool-choice support from compatibility flags. */
export declare function deriveToolChoiceSupport(compat: ToolChoiceCompat | undefined): {
    support: ToolChoiceSupport;
    source: "static" | "derived";
};
/** Returns the registry key used for runtime tool-choice capability overrides. */
export declare function toolChoiceRegistryKey(model: Model<Api>): string;
/** Returns the current runtime tool-choice capability override for a model. */
export declare function getToolChoiceCapabilityOverride(model: Model<Api>): ToolChoiceSupport | undefined;
/** Clears runtime tool-choice capability overrides for tests. */
export declare function clearToolChoiceIncapabilityRegistryForTests(): void;
/** Overrides durable-cache dependencies for isolated tests. */
export declare function configureToolChoiceCapabilityCacheForTests(options?: {
    path?: string;
    now?: () => number;
    beforeExpiredDelete?: () => void;
    beforeMalformedDelete?: () => void;
    onCacheOpen?: () => void;
    simulateOperationError?: () => Error | undefined;
    beforeCorruptRetire?: () => void;
    beforeLockExactUnlink?: (lockPath: string) => void;
}): void;
/** Records a discovered maximum supported tool-choice level for a model. */
export declare function markToolChoiceIncapability(model: Model<Api>, maxSupport: ToolChoiceSupport, reason?: string): void;
/**
 * Resolves a requested tool_choice against static and runtime capability limits.
 * `compat` overrides `model.compat` for transports that layer URL/provider
 * detection on top of explicit model overrides (e.g. resolveOpenAICompat).
 */
export declare function resolveToolChoice(model: Model<Api>, requested: ToolChoice | undefined, compat?: ToolChoiceCompat): ResolveToolChoiceResult;
/** Detects provider errors indicating forced tool_choice is unsupported. */
export declare function isForcedToolChoiceUnsupportedError(error: unknown, sentForcedToolChoice: boolean): boolean;
/**
 * Detects Codex's statusless SSE rejection for a named function tool choice.
 * This is intentionally separate from the shared HTTP-400 classifier.
 */
export declare function isCodexStatuslessNamedToolChoiceNotFoundError(error: unknown, forcedToolName: string | undefined, sentToolNames: readonly string[]): boolean;
export type { ToolChoiceCompat, ToolChoiceSupport, ToolChoiceSupportSource } from "../types";
export interface ResolveToolChoiceResult {
    requestedChoice: ToolChoice | undefined;
    requestedLevel: ToolChoiceSupport;
    resolvedChoice: ToolChoice | undefined;
    resolvedLevel: ToolChoiceSupport;
    support: ToolChoiceSupport;
    supportSource: ToolChoiceSupportSource;
    degraded: boolean;
    reason?: string;
    registryKey: string;
    targetToolName?: string;
}