fix(core): isolate vector metadata and search results

.changeset/clean-vector-search-results.md

@@ -0,0 +1,5 @@
+---
+"@voltagent/core": patch
+---
+
+Copy embeddings in in-memory vector search results and deep-clone metadata at the store, get and search boundaries so caller mutations do not corrupt stored memories or change subsequent user-filtered searches. Only selected search results are cloned.

packages/core/src/memory/adapters/vector/in-memory.spec.ts

@@ -0,0 +1,66 @@
+import { describe, expect, it } from "vitest";
+import { InMemoryVectorAdapter } from "./in-memory";
+
+describe("InMemoryVectorAdapter search result isolation", () => {
+  it.each(["search", "get", "store"])(
+    "isolates nested metadata at the %s boundary",
+    async (operation) => {
+      const adapter = new InMemoryVectorAdapter();
+      const metadata = { context: { labels: ["original"] } };
+      await adapter.store("memory", [1, 0], metadata);
+
+      if (operation === "store") {
+        metadata.context.labels.push("changed");
+      } else {
+        const result =
+          operation === "search" ? (await adapter.search([1, 0]))[0] : await adapter.get("memory");
+        const context = result?.metadata?.context as typeof metadata.context;
+        context.labels.push("changed");
+      }
+
+      expect((await adapter.get("memory"))?.metadata).toEqual({
+        context: { labels: ["original"] },
+      });
+    },
+  );
+
+  it("does not let a returned embedding corrupt future similarity searches", async () => {
+    const adapter = new InMemoryVectorAdapter();
+    await adapter.store("matching", [1, 0], { userId: "alice" });
+    await adapter.store("other", [0, 1], { userId: "alice" });
+
+    const [result] = await adapter.search([1, 0]);
+    result.vector[0] = 0;
+    result.vector[1] = 1;
+
+    expect((await adapter.get("matching"))?.vector).toEqual([1, 0]);
+    const [nextResult] = await adapter.search([1, 0]);
+    expect(nextResult.id).toBe("matching");
+    expect(nextResult.score).toBe(1);
+  });
+
+  it("does not let returned metadata change user-scoped retrieval", async () => {
+    const adapter = new InMemoryVectorAdapter();
+    await adapter.store("memory", [1, 0], { userId: "alice" });
+
+    const [result] = await adapter.search([1, 0], { filter: { userId: "alice" } });
+    if (!result.metadata) throw new Error("Expected stored metadata");
+    result.metadata.userId = "bob";
+
+    expect(await adapter.search([1, 0], { filter: { userId: "bob" } })).toEqual([]);
+    expect(await adapter.search([1, 0], { filter: { userId: "alice" } })).toHaveLength(1);
+    expect((await adapter.get("memory"))?.metadata).toEqual({ userId: "alice" });
+  });
+
+  it("supports results without metadata and keeps stored input isolated", async () => {
+    const adapter = new InMemoryVectorAdapter();
+    const vector = [1, 0];
+    await adapter.store("memory", vector);
+    vector[0] = 0;
+
+    const [result] = await adapter.search([1, 0]);
+    expect(result.vector).toEqual([1, 0]);
+    expect(result.metadata).toBeUndefined();
+    expect(result.score).toBe(1);
+  });
+});

packages/core/src/memory/adapters/vector/in-memory.ts

@@ -1,3 +1,4 @@
+import { deepClone } from "@voltagent/internal/utils";
 import { cosineSimilarity } from "../../utils/vector-math";
 import type { SearchResult, VectorAdapter, VectorItem } from "./types";
 
@@ -26,7 +27,7 @@ export class InMemoryVectorAdapter implements VectorAdapter {
     this.vectors.set(id, {
       id,
       vector: [...vector], // Clone to prevent external modifications
-      metadata: metadata ? { ...metadata } : undefined,
+      metadata: metadata ? deepClone(metadata) : undefined,
     });
   }
 
@@ -83,7 +84,11 @@ export class InMemoryVectorAdapter implements VectorAdapter {
     // Sort by score (descending) and limit results
     results.sort((a, b) => b.score - a.score);
 
-    return results.slice(0, limit);
+    return results.slice(0, limit).map((item) => ({
+      ...item,
+      vector: [...item.vector],
+      metadata: item.metadata ? deepClone(item.metadata) : undefined,
+    }));
   }
 
   async delete(id: string): Promise<void> {
@@ -115,7 +120,7 @@ export class InMemoryVectorAdapter implements VectorAdapter {
     return {
       ...item,
       vector: [...item.vector],
-      metadata: item.metadata ? { ...item.metadata } : undefined,
+      metadata: item.metadata ? deepClone(item.metadata) : undefined,
     };
   }