/**
 * RB-476-A stage 2 (ruling 2026-08-02, RB-476 "no compatibility surface survives", replay
 * resolution included) — the durable-name machinery this module used to hold is RETIRED:
 *
 *  - `OLD_TO_NEW` (the Q6/design-108/design-115 persisted-name normalization) and the MCP `mcp__`
 *    prefix arm are gone: a persisted checkpoint/orphan/policy entry carrying a pre-rename name no
 *    longer resolves to the live roster. Old durable state misses LOUDLY (`resume.tool_unavailable`
 *    on a resumed checkpoint, a roster miss on replay) — by ruling, old sessions are sacrificed
 *    rather than carried.
 *  - `canonicalToolName` is gone with it: with the mapping cleared it was the identity function, and
 *    keeping an identity shim invites the next mapping to grow back silently.
 *  - `TOMBSTONED_TOOLS` (per-name re-education messages) is gone: a retired name now gets the same
 *    loud generic roster miss as any unknown tool.
 *
 * What REMAINS is validation data: {@link RETIRED_TOOL_NAMES} maps every name the engine ever
 * retired to a one-line guidance string, and {@link judgeRuleToolName} is the ONE reading of it a rule's
 * tool name gets. They exist because deleting the mapping flips stale POLICY entries from "silently
 * matched" to "silently matches nothing" — and for a deny/requireApproval entry that direction WIDENS
 * the surface. `validatePermissionRules` (permission-rules.ts) does NOT classify retired names itself:
 * which names a deployment mounts its OWN tool under is a roster fact, and the judgment takes the roster.
 * A deployment that mounts its OWN tool under one of these names is unaffected: the name is then in the
 * roster and the judgment answers `current`.
 *
 * GRAMMAR of a guidance string, read by {@link judgeRuleToolName} and held by a pin: it opens with
 * `renamed "<name>"` (a 1:1 successor — the judgment's `currentName`), `folded into "<name>"` (merged into a
 * wider tool: writing it would deny more than the entry did, so it is no current name), or `removed — `.
 */
export declare const RETIRED_TOOL_NAMES: ReadonlyMap<string, string>;
/** The three answers {@link judgeRuleToolName} gives — a closed set. */
export declare const RULE_TOOL_NAME_VERDICTS: readonly ["current", "retired", "unprefixed_namespace"];
/**
 * Whether a tool name written in a rule is a stale name — one that, against `roster`, names no tool and never can:
 *  - `current` — not a stale name: the roster mounts it, or it is neither retired nor a prefix-less `__` name. (Whether a
 *    current name matches anything THIS run is a different question — an unknown name is the prepare audit's advisory.)
 *  - `retired` — a name in {@link RETIRED_TOOL_NAMES} the roster does not mount; `guidance` is that table's line, and
 *    `currentName` the 1:1 successor when there is one (see the module header's grammar).
 *  - `unprefixed_namespace` — carries the `__` namespace separator with no protocol prefix. The roster cannot clear it:
 *    a caller tool name or alias carrying `__` is refused at prepare, every engine tool name is `__`-free, and every
 *    protocol tool is minted with its prefix.
 *
 * `roster` = the tool names (aliases included) the reader knows are mounted: a run's assembled roster at prepare, the
 * names a deployment DECLARES it mounts its own tools under at a session-rule store (an empty set when it declares none).
 */
export type RuleToolNameVerdict = {
    readonly kind: "current";
} | {
    readonly kind: "retired";
    readonly guidance: string;
    readonly currentName?: string;
} | {
    readonly kind: "unprefixed_namespace";
};
/** See {@link RuleToolNameVerdict}. Pure; the one answer to "is this rule's tool name a retired or prefix-less name". */
export declare function judgeRuleToolName(name: string, roster: ReadonlySet<string>): RuleToolNameVerdict;