export const ENDPOINT_MODEL_SELECTION_ALLOWLIST: Readonly<{
  openrouter: readonly [
    "anthropic/claude-opus-5.5",
    "deepseek/deepseek-v4-flash-0731",
    "openai/gpt-6-luna",
    "anthropic/claude-sonnet-5.5",
  ];
  "openai-codex": readonly ["gpt-6.1-sol"];
}>;
export const ENDPOINT_MODEL_REASONING_EFFORTS: readonly [
  "none",
  "low",
  "medium",
  "high",
  "xhigh",
];
export const ENDPOINT_MODEL_MAX_FALLBACKS: 2;
export type EndpointModelStep = Readonly<{
  provider: string;
  model: string;
  reasoningEffort: (typeof ENDPOINT_MODEL_REASONING_EFFORTS)[number];
  runsApiBaseUrl?: string;
  modelConnectionId?: string;
}>;
export type EndpointModelSelection = Readonly<
  EndpointModelStep & {
    fallbackPolicy?: "STOP" | "PRODUCT_DEFAULT";
    fallbacks?: readonly EndpointModelStep[];
  }
>;
export type EndpointChainFailure =
  | "NATIVE_FAILED"
  | "OUTPUT_CONTRACT_FAILED"
  | "NOT_ADMITTED"
  | "STEP_UNAVAILABLE";
export type EndpointChainDecision =
  | Readonly<{
      advance: true;
      stepIndex: number;
      selection: EndpointModelStep;
    }>
  | Readonly<{
      advance: false;
      reason:
        | "INVALID"
        | "NOT_ADVANCEABLE"
        | "CHAIN_EXHAUSTED"
        | "NO_TIME_LEFT";
    }>;
export function normalizeRunsApiBaseUrl(value: unknown): string | null;
export function compileEndpointModelSelection(
  value: unknown
): EndpointModelSelection | null | "invalid";
export function endpointModelSelectionChain(
  selection: unknown
): EndpointModelStep[];
export function endpointModelSelectionSource(
  selection: { provider: string; runsApiBaseUrl?: string } | null | undefined
): "default" | "openrouter" | "codex" | "custom";
export const ENDPOINT_CHAIN_STEP_ADMISSION_MS: number;
export const ENDPOINT_CHAIN_MIN_STEP_MS: number;
export const ENDPOINT_CHAIN_ADVANCE_FAILURES: readonly EndpointChainFailure[];
export function nextEndpointChainStep(
  chain: readonly EndpointModelStep[],
  history: readonly string[],
  failure: string,
  remainingMs?: number
): EndpointChainDecision;
export function endpointChainStepAdmissionDeadline(input: {
  startedAtMs: number;
  deadlineMs: number;
  stepIndex: number;
  stepCount: number;
}): number;