fix: guard session tool results

src/agents/pi-embedded-runner.guard.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+
+import type { AgentMessage } from "@mariozechner/pi-agent-core";
+import { SessionManager } from "@mariozechner/pi-coding-agent";
+
+import { guardSessionManager } from "./session-tool-result-guard-wrapper.js";
+import { sanitizeToolUseResultPairing } from "./session-transcript-repair.js";
+
+function assistantToolCall(id: string): AgentMessage {
+  return {
+    role: "assistant",
+    content: [{ type: "toolCall", id, name: "n", arguments: {} }],
+  } as AgentMessage;
+}
+
+describe("guardSessionManager integration", () => {
+  it("persists synthetic toolResult before subsequent assistant message", () => {
+    const sm = guardSessionManager(SessionManager.inMemory());
+
+    sm.appendMessage(assistantToolCall("call_1"));
+    sm.appendMessage({
+      role: "assistant",
+      content: [{ type: "text", text: "followup" }],
+    } as AgentMessage);
+
+    const messages = sm
+      .getEntries()
+      .filter((e) => e.type === "message")
+      .map((e) => (e as { message: AgentMessage }).message);
+
+    expect(messages.map((m) => m.role)).toEqual([
+      "assistant",
+      "toolResult",
+      "assistant",
+    ]);
+    expect((messages[1] as { toolCallId?: string }).toolCallId).toBe("call_1");
+    expect(
+      sanitizeToolUseResultPairing(messages).map((m) => m.role),
+    ).toEqual(["assistant", "toolResult", "assistant"]);
+  });
+});
+