diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.e2e.test.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.e2e.test.ts
index 12df89495..d9ce20b07 100644
--- a/src/agents/pi-embedded-runner/run.overflow-compaction.e2e.test.ts
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.e2e.test.ts
@@ -1,91 +1,16 @@
-import { describe, expect, it, vi, beforeEach } from "vitest";
-
-vi.mock("./run/attempt.js", () => ({
-  runEmbeddedAttempt: vi.fn(),
-}));
-
-vi.mock("./compact.js", () => ({
-  compactEmbeddedPiSessionDirect: vi.fn(),
-}));
-
-vi.mock("./model.js", () => ({
-  resolveModel: vi.fn(() => ({
-    model: {
-      id: "test-model",
-      provider: "anthropic",
-      contextWindow: 200000,
-      api: "messages",
-    },
-    error: null,
-    authStorage: {
-      setRuntimeApiKey: vi.fn(),
-    },
-    modelRegistry: {},
-  })),
-}));
-
-vi.mock("../model-auth.js", () => ({
-  ensureAuthProfileStore: vi.fn(() => ({})),
-  getApiKeyForModel: vi.fn(async () => ({
-    apiKey: "test-key",
-    profileId: "test-profile",
-    source: "test",
-  })),
-  resolveAuthProfileOrder: vi.fn(() => []),
-}));
-
-vi.mock("../models-config.js", () => ({
-  ensureOpenClawModelsJson: vi.fn(async () => {}),
-}));
-
-vi.mock("../context-window-guard.js", () => ({
-  CONTEXT_WINDOW_HARD_MIN_TOKENS: 1000,
-  CONTEXT_WINDOW_WARN_BELOW_TOKENS: 5000,
-  evaluateContextWindowGuard: vi.fn(() => ({
-    shouldWarn: false,
-    shouldBlock: false,
-    tokens: 200000,
-    source: "model",
-  })),
-  resolveContextWindowInfo: vi.fn(() => ({
-    tokens: 200000,
-    source: "model",
-  })),
-}));
-
-vi.mock("../../process/command-queue.js", () => ({
-  enqueueCommandInLane: vi.fn((_lane: string, task: () => unknown) => task()),
-}));
+import "./run.overflow-compaction.mocks.shared.js";
+import { beforeEach, describe, expect, it, vi } from "vitest";
 
 vi.mock("../../utils.js", () => ({
   resolveUserPath: vi.fn((p: string) => p),
 }));
 
-vi.mock("../../utils/message-channel.js", () => ({
-  isMarkdownCapableMessageChannel: vi.fn(() => true),
-}));
-
-vi.mock("../agent-paths.js", () => ({
-  resolveOpenClawAgentDir: vi.fn(() => "/tmp/agent-dir"),
-}));
-
 vi.mock("../auth-profiles.js", () => ({
   markAuthProfileFailure: vi.fn(async () => {}),
   markAuthProfileGood: vi.fn(async () => {}),
   markAuthProfileUsed: vi.fn(async () => {}),
 }));
 
-vi.mock("../defaults.js", () => ({
-  DEFAULT_CONTEXT_TOKENS: 200000,
-  DEFAULT_MODEL: "test-model",
-  DEFAULT_PROVIDER: "anthropic",
-}));
-
-vi.mock("../failover-error.js", () => ({
-  FailoverError: class extends Error {},
-  resolveFailoverStatus: vi.fn(),
-}));
-
 vi.mock("../usage.js", () => ({
   normalizeUsage: vi.fn((usage?: unknown) =>
     usage && typeof usage === "object" ? usage : undefined,
@@ -105,43 +30,6 @@ vi.mock("../usage.js", () => ({
   hasNonzeroUsage: vi.fn(() => false),
 }));
 
-vi.mock("./lanes.js", () => ({
-  resolveSessionLane: vi.fn(() => "session-lane"),
-  resolveGlobalLane: vi.fn(() => "global-lane"),
-}));
-
-vi.mock("./logger.js", () => ({
-  log: {
-    debug: vi.fn(),
-    info: vi.fn(),
-    warn: vi.fn(),
-    error: vi.fn(),
-    isEnabled: vi.fn(() => false),
-  },
-}));
-
-vi.mock("./run/payloads.js", () => ({
-  buildEmbeddedRunPayloads: vi.fn(() => []),
-}));
-
-vi.mock("./tool-result-truncation.js", () => ({
-  truncateOversizedToolResultsInSession: vi.fn(async () => ({
-    truncated: false,
-    truncatedCount: 0,
-    reason: "no oversized tool results",
-  })),
-  sessionLikelyHasOversizedToolResults: vi.fn(() => false),
-}));
-
-vi.mock("./utils.js", () => ({
-  describeUnknownError: vi.fn((err: unknown) => {
-    if (err instanceof Error) {
-      return err.message;
-    }
-    return String(err);
-  }),
-}));
-
 vi.mock("../pi-embedded-helpers.js", async () => {
   return {
     isCompactionFailureError: (msg?: string) => {
@@ -184,10 +72,10 @@ vi.mock("../pi-embedded-helpers.js", async () => {
   };
 });
 
-import type { EmbeddedRunAttemptResult } from "./run/types.js";
 import { compactEmbeddedPiSessionDirect } from "./compact.js";
 import { log } from "./logger.js";
 import { runEmbeddedPiAgent } from "./run.js";
+import { makeAttemptResult } from "./run.overflow-compaction.fixture.js";
 import { runEmbeddedAttempt } from "./run/attempt.js";
 import {
   sessionLikelyHasOversizedToolResults,
@@ -201,27 +89,6 @@ const mockedTruncateOversizedToolResultsInSession = vi.mocked(
   truncateOversizedToolResultsInSession,
 );
 
-function makeAttemptResult(
-  overrides: Partial<EmbeddedRunAttemptResult> = {},
-): EmbeddedRunAttemptResult {
-  return {
-    aborted: false,
-    timedOut: false,
-    timedOutDuringCompaction: false,
-    promptError: null,
-    sessionIdUsed: "test-session",
-    assistantTexts: ["Hello!"],
-    toolMetas: [],
-    lastAssistant: undefined,
-    messagesSnapshot: [],
-    didSendViaMessagingTool: false,
-    messagingToolSentTexts: [],
-    messagingToolSentTargets: [],
-    cloudCodeAssistFormatError: false,
-    ...overrides,
-  };
-}
-
 const baseParams = {
   sessionId: "test-session",
   sessionKey: "test-key",
diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.fixture.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.fixture.ts
new file mode 100644
index 000000000..2ba720f2a
--- /dev/null
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.fixture.ts
@@ -0,0 +1,22 @@
+import type { EmbeddedRunAttemptResult } from "./run/types.js";
+
+export function makeAttemptResult(
+  overrides: Partial<EmbeddedRunAttemptResult> = {},
+): EmbeddedRunAttemptResult {
+  return {
+    aborted: false,
+    timedOut: false,
+    timedOutDuringCompaction: false,
+    promptError: null,
+    sessionIdUsed: "test-session",
+    assistantTexts: ["Hello!"],
+    toolMetas: [],
+    lastAssistant: undefined,
+    messagesSnapshot: [],
+    didSendViaMessagingTool: false,
+    messagingToolSentTexts: [],
+    messagingToolSentTargets: [],
+    cloudCodeAssistFormatError: false,
+    ...overrides,
+  };
+}
diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts
new file mode 100644
index 000000000..407788564
--- /dev/null
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.mocks.shared.ts
@@ -0,0 +1,114 @@
+import { vi } from "vitest";
+
+vi.mock("./run/attempt.js", () => ({
+  runEmbeddedAttempt: vi.fn(),
+}));
+
+vi.mock("./compact.js", () => ({
+  compactEmbeddedPiSessionDirect: vi.fn(),
+}));
+
+vi.mock("./model.js", () => ({
+  resolveModel: vi.fn(() => ({
+    model: {
+      id: "test-model",
+      provider: "anthropic",
+      contextWindow: 200000,
+      api: "messages",
+    },
+    error: null,
+    authStorage: {
+      setRuntimeApiKey: vi.fn(),
+    },
+    modelRegistry: {},
+  })),
+}));
+
+vi.mock("../model-auth.js", () => ({
+  ensureAuthProfileStore: vi.fn(() => ({})),
+  getApiKeyForModel: vi.fn(async () => ({
+    apiKey: "test-key",
+    profileId: "test-profile",
+    source: "test",
+  })),
+  resolveAuthProfileOrder: vi.fn(() => []),
+}));
+
+vi.mock("../models-config.js", () => ({
+  ensureOpenClawModelsJson: vi.fn(async () => {}),
+}));
+
+vi.mock("../context-window-guard.js", () => ({
+  CONTEXT_WINDOW_HARD_MIN_TOKENS: 1000,
+  CONTEXT_WINDOW_WARN_BELOW_TOKENS: 5000,
+  evaluateContextWindowGuard: vi.fn(() => ({
+    shouldWarn: false,
+    shouldBlock: false,
+    tokens: 200000,
+    source: "model",
+  })),
+  resolveContextWindowInfo: vi.fn(() => ({
+    tokens: 200000,
+    source: "model",
+  })),
+}));
+
+vi.mock("../../process/command-queue.js", () => ({
+  enqueueCommandInLane: vi.fn((_lane: string, task: () => unknown) => task()),
+}));
+
+vi.mock("../../utils/message-channel.js", () => ({
+  isMarkdownCapableMessageChannel: vi.fn(() => true),
+}));
+
+vi.mock("../agent-paths.js", () => ({
+  resolveOpenClawAgentDir: vi.fn(() => "/tmp/agent-dir"),
+}));
+
+vi.mock("../defaults.js", () => ({
+  DEFAULT_CONTEXT_TOKENS: 200000,
+  DEFAULT_MODEL: "test-model",
+  DEFAULT_PROVIDER: "anthropic",
+}));
+
+vi.mock("../failover-error.js", () => ({
+  FailoverError: class extends Error {},
+  resolveFailoverStatus: vi.fn(),
+}));
+
+vi.mock("./lanes.js", () => ({
+  resolveSessionLane: vi.fn(() => "session-lane"),
+  resolveGlobalLane: vi.fn(() => "global-lane"),
+}));
+
+vi.mock("./logger.js", () => ({
+  log: {
+    debug: vi.fn(),
+    info: vi.fn(),
+    warn: vi.fn(),
+    error: vi.fn(),
+    isEnabled: vi.fn(() => false),
+  },
+}));
+
+vi.mock("./run/payloads.js", () => ({
+  buildEmbeddedRunPayloads: vi.fn(() => []),
+}));
+
+vi.mock("./tool-result-truncation.js", () => ({
+  truncateOversizedToolResultsInSession: vi.fn(async () => ({
+    truncated: false,
+    truncatedCount: 0,
+    reason: "no oversized tool results",
+  })),
+  sessionLikelyHasOversizedToolResults: vi.fn(() => false),
+}));
+
+vi.mock("./utils.js", () => ({
+  describeUnknownError: vi.fn((err: unknown) => {
+    if (err instanceof Error) {
+      return err.message;
+    }
+    return String(err);
+  }),
+}));
diff --git a/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts b/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
index 1a2c29791..ded9da42c 100644
--- a/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
+++ b/src/agents/pi-embedded-runner/run.overflow-compaction.test.ts
@@ -1,70 +1,6 @@
+import "./run.overflow-compaction.mocks.shared.js";
 import { beforeEach, describe, expect, it, vi } from "vitest";
 
-vi.mock("./run/attempt.js", () => ({
-  runEmbeddedAttempt: vi.fn(),
-}));
-
-vi.mock("./compact.js", () => ({
-  compactEmbeddedPiSessionDirect: vi.fn(),
-}));
-
-vi.mock("./model.js", () => ({
-  resolveModel: vi.fn(() => ({
-    model: {
-      id: "test-model",
-      provider: "anthropic",
-      contextWindow: 200000,
-      api: "messages",
-    },
-    error: null,
-    authStorage: {
-      setRuntimeApiKey: vi.fn(),
-    },
-    modelRegistry: {},
-  })),
-}));
-
-vi.mock("../model-auth.js", () => ({
-  ensureAuthProfileStore: vi.fn(() => ({})),
-  getApiKeyForModel: vi.fn(async () => ({
-    apiKey: "test-key",
-    profileId: "test-profile",
-    source: "test",
-  })),
-  resolveAuthProfileOrder: vi.fn(() => []),
-}));
-
-vi.mock("../models-config.js", () => ({
-  ensureOpenClawModelsJson: vi.fn(async () => {}),
-}));
-
-vi.mock("../context-window-guard.js", () => ({
-  CONTEXT_WINDOW_HARD_MIN_TOKENS: 1000,
-  CONTEXT_WINDOW_WARN_BELOW_TOKENS: 5000,
-  evaluateContextWindowGuard: vi.fn(() => ({
-    shouldWarn: false,
-    shouldBlock: false,
-    tokens: 200000,
-    source: "model",
-  })),
-  resolveContextWindowInfo: vi.fn(() => ({
-    tokens: 200000,
-    source: "model",
-  })),
-}));
-
-vi.mock("../../process/command-queue.js", () => ({
-  enqueueCommandInLane: vi.fn((_lane: string, task: () => unknown) => task()),
-}));
-
-vi.mock("../../utils/message-channel.js", () => ({
-  isMarkdownCapableMessageChannel: vi.fn(() => true),
-}));
-
-vi.mock("../agent-paths.js", () => ({
-  resolveOpenClawAgentDir: vi.fn(() => "/tmp/agent-dir"),
-}));
-
 vi.mock("../auth-profiles.js", () => ({
   isProfileInCooldown: vi.fn(() => false),
   markAuthProfileFailure: vi.fn(async () => {}),
@@ -72,17 +8,6 @@ vi.mock("../auth-profiles.js", () => ({
   markAuthProfileUsed: vi.fn(async () => {}),
 }));
 
-vi.mock("../defaults.js", () => ({
-  DEFAULT_CONTEXT_TOKENS: 200000,
-  DEFAULT_MODEL: "test-model",
-  DEFAULT_PROVIDER: "anthropic",
-}));
-
-vi.mock("../failover-error.js", () => ({
-  FailoverError: class extends Error {},
-  resolveFailoverStatus: vi.fn(),
-}));
-
 vi.mock("../usage.js", () => ({
   normalizeUsage: vi.fn((usage?: unknown) =>
     usage && typeof usage === "object" ? usage : undefined,
@@ -111,43 +36,6 @@ vi.mock("../workspace-run.js", () => ({
   redactRunIdentifier: vi.fn((value?: string) => value ?? ""),
 }));
 
-vi.mock("./lanes.js", () => ({
-  resolveSessionLane: vi.fn(() => "session-lane"),
-  resolveGlobalLane: vi.fn(() => "global-lane"),
-}));
-
-vi.mock("./logger.js", () => ({
-  log: {
-    debug: vi.fn(),
-    info: vi.fn(),
-    warn: vi.fn(),
-    error: vi.fn(),
-    isEnabled: vi.fn(() => false),
-  },
-}));
-
-vi.mock("./run/payloads.js", () => ({
-  buildEmbeddedRunPayloads: vi.fn(() => []),
-}));
-
-vi.mock("./tool-result-truncation.js", () => ({
-  truncateOversizedToolResultsInSession: vi.fn(async () => ({
-    truncated: false,
-    truncatedCount: 0,
-    reason: "no oversized tool results",
-  })),
-  sessionLikelyHasOversizedToolResults: vi.fn(() => false),
-}));
-
-vi.mock("./utils.js", () => ({
-  describeUnknownError: vi.fn((err: unknown) => {
-    if (err instanceof Error) {
-      return err.message;
-    }
-    return String(err);
-  }),
-}));
-
 vi.mock("../pi-embedded-helpers.js", () => ({
   formatBillingErrorMessage: vi.fn(() => ""),
   classifyFailoverReason: vi.fn(() => null),
@@ -168,35 +56,14 @@ vi.mock("../pi-embedded-helpers.js", () => ({
   pickFallbackThinkingLevel: vi.fn(() => null),
 }));
 
-import type { EmbeddedRunAttemptResult } from "./run/types.js";
 import { compactEmbeddedPiSessionDirect } from "./compact.js";
 import { runEmbeddedPiAgent } from "./run.js";
+import { makeAttemptResult } from "./run.overflow-compaction.fixture.js";
 import { runEmbeddedAttempt } from "./run/attempt.js";
 
 const mockedRunEmbeddedAttempt = vi.mocked(runEmbeddedAttempt);
 const mockedCompactDirect = vi.mocked(compactEmbeddedPiSessionDirect);
 
-function makeAttemptResult(
-  overrides: Partial<EmbeddedRunAttemptResult> = {},
-): EmbeddedRunAttemptResult {
-  return {
-    aborted: false,
-    timedOut: false,
-    timedOutDuringCompaction: false,
-    promptError: null,
-    sessionIdUsed: "test-session",
-    assistantTexts: ["Hello!"],
-    toolMetas: [],
-    lastAssistant: undefined,
-    messagesSnapshot: [],
-    didSendViaMessagingTool: false,
-    messagingToolSentTexts: [],
-    messagingToolSentTargets: [],
-    cloudCodeAssistFormatError: false,
-    ...overrides,
-  };
-}
-
 describe("runEmbeddedPiAgent overflow compaction trigger routing", () => {
   beforeEach(() => {
     vi.clearAllMocks();