/**
 * embeddingSummary — what a recording keeps of a vector: its shape, not its
 * bytes.
 *
 * Pattern: pure copy-on-write projection, in the `storedPreview` family —
 *          "summarise structured values rather than serialize them", applied
 *          to the one field measured to dominate a recording's size.
 * Role:    recorders/observability layer. Applied at the RECORDING boundary
 *          (BoundaryRecorder payload capture, `recordRun` freeze), never to
 *          live run state — stages and stores keep their real vectors.
 * Emits:   N/A.
 *
 * ── The measurement this exists for ─────────────────────────────────────────
 * A single retrieval turn's recording measured 2.76 MB in a production RAG
 * deployment — about 1.1 MB of it embedding floats, because the memory-read
 * subflow's boundary output carries every retrieved entry, and every entry
 * carries its full vector (1,024 floats serializing at ~19 bytes each). No
 * consumer of a recording reads those floats: retrieval debugging needs the
 * score, the passage, the document and the rejected candidates — all of which
 * live in the retrieval evidence and none of which this touches. The vector's
 * only recording-worthy facts are that it existed, its dimensionality, and a
 * checksum-grade magnitude. That is exactly what `{ dims, norm }` keeps.
 *
 * The walk is copy-on-write: a value with no embeddings anywhere is returned
 * BY REFERENCE, so the common payload costs one traversal and zero
 * allocation. It never mutates its input — recordings share structure with
 * live run state, and live state is borrowed, not owned.
 *
 * Two spellings are recognised, because the memory layer writes both:
 *   - `embedding: number[]`     — a `MemoryEntry`'s vector (read side);
 *   - `embeddings: number[][]`  — the write pipeline's per-message batch.
 *
 * Idempotent by construction: a summary is not a numeric array, so a value
 * that has already been summarised passes through unchanged.
 */
/** What remains of a vector in a recording: dimensionality and L2 norm. */
export interface EmbeddingSummary {
    readonly dims: number;
    readonly norm: number;
}
/** Summarise one vector. Exported for consumers that render recordings. */
export declare function summarizeVector(vector: readonly number[]): EmbeddingSummary;
/**
 * Replace every `embedding` / `embeddings` field in a JSON-ish value with its
 * `{ dims, norm }` summary. Copy-on-write: returns the SAME reference when
 * nothing needed replacing; otherwise a structurally-shared copy. Never
 * mutates the input.
 *
 * Shared nodes stay shared: a snapshot holds the same entry object at several
 * paths (live state, stage writes, commit history), so results are memoized
 * per input object — every path gets the SAME summarized copy, not one copy
 * and one raw leak. Cycle-safe: an object seen again while still being walked
 * resolves to its original reference (a cyclic value could not be serialized
 * anyway).
 */
export declare function summarizeEmbeddings(value: unknown): unknown;