/**
 * Memory pressure thresholds.
 *
 * Steve 2026-05-15 dogfood: macOS keeps the "memory used %" stat at
 * 95-99% on virtually every Mac because the OS aggressively uses RAM
 * for file cache (which is reclaimable on demand). Gating spawns purely
 * on usedPercent meant the user's machine permanently skipped every
 * wake action — agents could never come back online. Concrete signal
 * from the log: `consecutiveSkips` climbing past 450 with freeMB
 * fluctuating 80-800 (i.e. plenty of real headroom most of the time).
 *
 * The fix: keep the percent check as a soft signal, but only DECLARE
 * memory pressure when freeMB drops below an absolute headroom floor.
 * A fresh Claude Code process is ~150-200MB RSS; reserve 300MB so we
 * never spawn into an actual OOM situation while letting the cache-
 * inflated 95-99% percent reading pass.
 *
 * Steve 2026-05-22 dogfood follow-up: even with the 300MB floor, the
 * gate fires constantly on macOS because `os.freemem()` only counts
 * STRICTLY-FREE pages — it excludes inactive + speculative pages that
 * the kernel can reclaim on demand. On a typical Mac with 3GB+ of
 * reclaimable cache, os.freemem() routinely reports 50-200MB while
 * Activity Monitor / `vm_stat` show 3-4GB available. The reconciler
 * was effectively never letting wakes through.
 *
 * Real fix: on macOS use `vm_stat` to compute AVAILABLE memory
 * (free + inactive + speculative), which is what the kernel itself
 * uses for OOM decisions. Linux's `os.freemem()` is accurate and
 * keeps the old path.
 */
export declare const MEMORY_PRESSURE_SPAWN_THRESHOLD = 90;
export declare const MEMORY_PRESSURE_MIN_FREE_MB = 300;
/**
 * Get the platform-appropriate free-memory reading in bytes.
 *
 * Exposed for tests; production callers should use {@link getMemoryStats}
 * or {@link isUnderMemoryPressure} instead.
 *
 * @returns free memory in bytes; falls back to os.freemem() if the
 *   macOS vm_stat parse fails.
 */
export declare function getAvailableMemoryBytes(): number;
/**
 * Check if the system is under memory pressure.
 *
 * Returns true only when BOTH:
 *   - usedPercent >= MEMORY_PRESSURE_SPAWN_THRESHOLD (90%), AND
 *   - freeMB < MEMORY_PRESSURE_MIN_FREE_MB (300MB)
 *
 * On macOS, "free" includes reclaimable inactive+speculative pages
 * (parsed from `vm_stat`) — without this the reading is ~50MB on a
 * Mac that actually has gigabytes of headroom, and the gate would
 * fire constantly. See module-doc comment for the dogfood history.
 *
 * @returns true if system should NOT spawn new processes
 */
export declare function isUnderMemoryPressure(): boolean;
/**
 * Get current memory usage stats.
 * @returns Object with totalMB, freeMB, usedPercent
 */
export declare function getMemoryStats(): {
    totalMB: number;
    freeMB: number;
    usedPercent: number;
    swapUsedPercent?: number;
    pressureElevated?: boolean;
};
/**
 * Swap use and the kernel's own pressure verdict.
 *
 * "Available" memory counts inactive pages as free, which on macOS stays
 * in the gigabytes even while the machine is swapping itself to a crawl
 * (2026-09-23: 10.7 of 12 GB swap, 7 GB compressed, load 117 — and the
 * idle-stop gate still read "memory is fine"). Swap fill and
 * `kern.memorystatus_vm_pressure_level` (1 normal, 2 warn, 4 critical)
 * see that; on Linux, SwapTotal/SwapFree from /proc/meminfo.
 *
 * @returns Swap share in use and whether the OS reports pressure, or null if unreadable
 */
export declare function readSwapPressure(): {
    swapUsedPercent: number;
    pressureElevated: boolean;
} | null;
/** Reset the swap reading cache — test affordance. */
export declare function _resetSwapCacheForTesting(): void;
/** Reset the vm_stat cache — test affordance. */
export declare function _resetVmStatCacheForTesting(): void;
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