Gateway: fix multi-agent sessions.usage discovery (#11523)

* Gateway: fix multi-agent sessions.usage discovery

* Gateway: resolve sessions.usage keys via sessionId

src/gateway/server-methods/usage.sessions-usage.test.ts

@@ -0,0 +1,146 @@
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("../../config/config.js", () => {
+  return {
+    loadConfig: vi.fn(() => ({
+      agents: {
+        list: [{ id: "main" }, { id: "opus" }],
+      },
+      session: {},
+    })),
+  };
+});
+
+vi.mock("../session-utils.js", async () => {
+  const actual = await vi.importActual<typeof import("../session-utils.js")>("../session-utils.js");
+  return {
+    ...actual,
+    loadCombinedSessionStoreForGateway: vi.fn(() => ({ storePath: "(multiple)", store: {} })),
+  };
+});
+
+vi.mock("../../infra/session-cost-usage.js", async () => {
+  const actual = await vi.importActual<typeof import("../../infra/session-cost-usage.js")>(
+    "../../infra/session-cost-usage.js",
+  );
+  return {
+    ...actual,
+    discoverAllSessions: vi.fn(async (params?: { agentId?: string }) => {
+      if (params?.agentId === "main") {
+        return [
+          {
+            sessionId: "s-main",
+            sessionFile: "/tmp/agents/main/sessions/s-main.jsonl",
+            mtime: 100,
+            firstUserMessage: "hello",
+          },
+        ];
+      }
+      if (params?.agentId === "opus") {
+        return [
+          {
+            sessionId: "s-opus",
+            sessionFile: "/tmp/agents/opus/sessions/s-opus.jsonl",
+            mtime: 200,
+            firstUserMessage: "hi",
+          },
+        ];
+      }
+      return [];
+    }),
+    loadSessionCostSummary: vi.fn(async () => ({
+      input: 0,
+      output: 0,
+      cacheRead: 0,
+      cacheWrite: 0,
+      totalTokens: 0,
+      totalCost: 0,
+      inputCost: 0,
+      outputCost: 0,
+      cacheReadCost: 0,
+      cacheWriteCost: 0,
+      missingCostEntries: 0,
+    })),
+  };
+});
+
+import { discoverAllSessions } from "../../infra/session-cost-usage.js";
+import { loadCombinedSessionStoreForGateway } from "../session-utils.js";
+import { usageHandlers } from "./usage.js";
+
+describe("sessions.usage", () => {
+  beforeEach(() => {
+    vi.useRealTimers();
+    vi.clearAllMocks();
+  });
+
+  it("discovers sessions across configured agents and keeps agentId in key", async () => {
+    const respond = vi.fn();
+
+    await usageHandlers["sessions.usage"]({
+      respond,
+      params: {
+        startDate: "2026-02-01",
+        endDate: "2026-02-02",
+        limit: 10,
+      },
+    } as unknown as Parameters<(typeof usageHandlers)["sessions.usage"]>[0]);
+
+    expect(vi.mocked(discoverAllSessions)).toHaveBeenCalledTimes(2);
+    expect(vi.mocked(discoverAllSessions).mock.calls[0]?.[0]?.agentId).toBe("main");
+    expect(vi.mocked(discoverAllSessions).mock.calls[1]?.[0]?.agentId).toBe("opus");
+
+    expect(respond).toHaveBeenCalledTimes(1);
+    expect(respond.mock.calls[0]?.[0]).toBe(true);
+    const result = respond.mock.calls[0]?.[1] as unknown as { sessions: Array<unknown> };
+    expect(result.sessions).toHaveLength(2);
+
+    // Sorted by most recent first (mtime=200 -> opus first).
+    expect(result.sessions[0].key).toBe("agent:opus:s-opus");
+    expect(result.sessions[0].agentId).toBe("opus");
+    expect(result.sessions[1].key).toBe("agent:main:s-main");
+    expect(result.sessions[1].agentId).toBe("main");
+  });
+
+  it("resolves store entries by sessionId when queried via discovered agent-prefixed key", async () => {
+    const storeKey = "agent:opus:slack:dm:u123";
+    const tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-usage-test-"));
+    const sessionFile = path.join(tempDir, "s-opus.jsonl");
+    fs.writeFileSync(sessionFile, "", "utf-8");
+    const respond = vi.fn();
+
+    // Swap the store mock for this test: the canonical key differs from the discovered key
+    // but points at the same sessionId.
+    vi.mocked(loadCombinedSessionStoreForGateway).mockReturnValue({
+      storePath: "(multiple)",
+      store: {
+        [storeKey]: {
+          sessionId: "s-opus",
+          sessionFile,
+          label: "Named session",
+          updatedAt: 999,
+        },
+      },
+    });
+
+    // Query via discovered key: agent:<id>:<sessionId>
+    await usageHandlers["sessions.usage"]({
+      respond,
+      params: {
+        startDate: "2026-02-01",
+        endDate: "2026-02-02",
+        key: "agent:opus:s-opus",
+        limit: 10,
+      },
+    } as unknown as Parameters<(typeof usageHandlers)["sessions.usage"]>[0]);
+
+    expect(respond).toHaveBeenCalledTimes(1);
+    expect(respond.mock.calls[0]?.[0]).toBe(true);
+    const result = respond.mock.calls[0]?.[1] as unknown as { sessions: Array<{ key: string }> };
+    expect(result.sessions).toHaveLength(1);
+    expect(result.sessions[0]?.key).toBe(storeKey);
+  });
+});