/**
 * Context Window Registry
 *
 * Accurate per-provider, per-model context window sizes (INPUT token limits).
 * These are distinct from OUTPUT token limits in tokens.ts.
 *
 * Sources:
 * - Anthropic: https://docs.anthropic.com/en/docs/about-claude/models
 * - OpenAI: https://platform.openai.com/docs/models
 * - Google: https://ai.google.dev/gemini-api/docs/models
 * - Others: Provider documentation as of Feb 2026
 */
/** Default context window when provider/model is unknown */
export declare const DEFAULT_CONTEXT_WINDOW = 128000;
/** Maximum output reserve when maxTokens not specified */
export declare const MAX_DEFAULT_OUTPUT_RESERVE = 64000;
/** Default output reserve ratio (35% of context) */
export declare const DEFAULT_OUTPUT_RESERVE_RATIO = 0.35;
/**
 * Per-provider, per-model context window sizes.
 * The "_default" key is the fallback for unknown models within a provider.
 */
export declare const MODEL_CONTEXT_WINDOWS: Record<string, Record<string, number>>;
/**
 * Resolve context window size for a provider/model combination.
 *
 * Priority:
 *  0. Dynamic model registry (DynamicModelProvider) — resolves cross-provider
 *     models (e.g. Claude on Vertex) that the static table cannot handle
 *  1. Exact model match under provider in static registry
 *  2. Prefix match under provider in static registry
 *  3. Provider's _default in static registry
 *  4. Global DEFAULT_CONTEXT_WINDOW
 */
export declare function getContextWindowSize(provider: string, model?: string): number;
/**
 * Calculate output token reserve for a given context window.
 *
 * Returns the *real* token count that will be reserved for output so callers
 * (`getAvailableInputTokens`, `BudgetChecker`, conversation-memory pruning, file
 * summarisation) compute input budget against the actual outgoing maxTokens.
 *
 * @param contextWindow - Total context window size
 * @param maxTokens - Explicit maxTokens from user config (if set)
 * @returns Number of tokens reserved for output (matches what's sent upstream)
 */
export declare function getOutputReserve(contextWindow: number, maxTokens?: number): number;
/**
 * Calculate available input tokens for a given provider/model.
 *
 * available = contextWindow - outputReserve
 */
export declare function getAvailableInputTokens(provider: string, model?: string, maxTokens?: number): number;