fix: add safeguard compaction tool summaries

src/agents/pi-extensions/compaction-safeguard.test.ts

@@ -0,0 +1,98 @@
+import type { AgentMessage } from "@mariozechner/pi-agent-core";
+import { describe, expect, it } from "vitest";
+
+import { __testing } from "./compaction-safeguard.js";
+
+const { collectToolFailures, formatToolFailuresSection } = __testing;
+
+describe("compaction-safeguard tool failures", () => {
+  it("formats tool failures with meta and summary", () => {
+    const messages: AgentMessage[] = [
+      {
+        role: "toolResult",
+        toolCallId: "call-1",
+        toolName: "exec",
+        isError: true,
+        details: { status: "failed", exitCode: 1 },
+        content: [{ type: "text", text: "ENOENT: missing file" }],
+        timestamp: Date.now(),
+      },
+      {
+        role: "toolResult",
+        toolCallId: "call-2",
+        toolName: "read",
+        isError: false,
+        content: [{ type: "text", text: "ok" }],
+        timestamp: Date.now(),
+      },
+    ];
+
+    const failures = collectToolFailures(messages);
+    expect(failures).toHaveLength(1);
+
+    const section = formatToolFailuresSection(failures);
+    expect(section).toContain("## Tool Failures");
+    expect(section).toContain("exec (status=failed exitCode=1): ENOENT: missing file");
+  });
+
+  it("dedupes by toolCallId and handles empty output", () => {
+    const messages: AgentMessage[] = [
+      {
+        role: "toolResult",
+        toolCallId: "call-1",
+        toolName: "exec",
+        isError: true,
+        details: { exitCode: 2 },
+        content: [],
+        timestamp: Date.now(),
+      },
+      {
+        role: "toolResult",
+        toolCallId: "call-1",
+        toolName: "exec",
+        isError: true,
+        content: [{ type: "text", text: "ignored" }],
+        timestamp: Date.now(),
+      },
+    ];
+
+    const failures = collectToolFailures(messages);
+    expect(failures).toHaveLength(1);
+
+    const section = formatToolFailuresSection(failures);
+    expect(section).toContain("exec (exitCode=2): failed");
+  });
+
+  it("caps the number of failures and adds overflow line", () => {
+    const messages: AgentMessage[] = Array.from({ length: 9 }, (_, idx) => ({
+      role: "toolResult",
+      toolCallId: `call-${idx}`,
+      toolName: "exec",
+      isError: true,
+      content: [{ type: "text", text: `error ${idx}` }],
+      timestamp: Date.now(),
+    }));
+
+    const failures = collectToolFailures(messages);
+    const section = formatToolFailuresSection(failures);
+    expect(section).toContain("## Tool Failures");
+    expect(section).toContain("...and 1 more");
+  });
+
+  it("omits section when there are no tool failures", () => {
+    const messages: AgentMessage[] = [
+      {
+        role: "toolResult",
+        toolCallId: "ok",
+        toolName: "exec",
+        isError: false,
+        content: [{ type: "text", text: "ok" }],
+        timestamp: Date.now(),
+      },
+    ];
+
+    const failures = collectToolFailures(messages);
+    const section = formatToolFailuresSection(failures);
+    expect(section).toBe("");
+  });
+});