fix(acpx): preserve Unicode in catalog tool arguments (#109589)

Co-authored-by: Peter Steinberger <steipete@gmail.com>

extensions/acpx/src/pi-session-catalog.test.ts

@@ -50,6 +50,7 @@ const originalPath = process.env.PATH;
 async function createPiStore(
   assistantText = "hi",
   sessionName = "Pi catalog session",
+  toolArguments: unknown = { command: "pwd" },
 ): Promise<string> {
   const directory = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-pi-catalog-"));
   temporaryDirectories.push(directory);
@@ -82,7 +83,7 @@ async function createPiStore(
         content: [
           { type: "thinking", thinking: "thinking" },
           { type: "text", text: assistantText },
-          { type: "toolCall", id: "call-1", name: "bash", arguments: { command: "pwd" } },
+          { type: "toolCall", id: "call-1", name: "bash", arguments: toolArguments },
         ],
       },
     },
@@ -293,6 +294,19 @@ describe("Pi session catalog", () => {
     expect(Buffer.byteLength(JSON.stringify(transcript), "utf8")).toBeLessThan(20 * 1024 * 1024);
   });
 
+  it("keeps truncated tool arguments on a valid UTF-16 boundary", async () => {
+    await createPiStore("hi", "Pi catalog session", {
+      value: `${"x".repeat(19_989)}🎉`,
+    });
+    const transcript = await readLocalPiTranscriptPage({ threadId: "pi-session", limit: 20 });
+    const toolCall = transcript.items.find((item) => item.type === "toolCall");
+
+    expect(toolCall?.text).toMatch(/…$/u);
+    expect(toolCall?.text).not.toMatch(
+      /[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?<![\uD800-\uDBFF])[\uDC00-\uDFFF]/u,
+    );
+  });
+
   it("reads legacy linear sessions and visible extended messages", async () => {
     const directory = await createPiStore();
     const entries = [

extensions/acpx/src/pi-session-catalog.ts

@@ -5,6 +5,7 @@ import type {
   SessionsCatalogReadResult,
 } from "openclaw/plugin-sdk/session-catalog";
 import { isRecord } from "openclaw/plugin-sdk/string-coerce-runtime";
+import { truncateUtf16Safe } from "openclaw/plugin-sdk/text-utility-runtime";
 import { listPiSummaryPage, readPiSessionById } from "./pi-session-store.js";
 
 const LOCAL_HOST_ID = "gateway";
@@ -225,7 +226,7 @@ function isoTimestamp(
 function jsonText(value: unknown, maxLength = 20_000): string | undefined {
   try {
     const text = JSON.stringify(value);
-    return text.length > maxLength ? `${text.slice(0, maxLength)}…` : text;
+    return text.length > maxLength ? `${truncateUtf16Safe(text, maxLength)}…` : text;
   } catch {
     return undefined;
   }