diff --git a/packages/app/src/types/stream.test.ts b/packages/app/src/types/stream.test.ts
index 019f08302..653194039 100644
--- a/packages/app/src/types/stream.test.ts
+++ b/packages/app/src/types/stream.test.ts
@@ -99,6 +99,21 @@ function todoTimeline(items: { text: string; completed: boolean }[]): AgentStrea
   };
 }
 
+function compactionTimeline(
+  status: "loading" | "completed",
+  trigger?: "auto" | "manual",
+): AgentStreamEventPayload {
+  return {
+    type: "timeline",
+    provider: "pi",
+    item: {
+      type: "compaction",
+      status,
+      ...(trigger ? { trigger } : {}),
+    },
+  };
+}
+
 function findToolByCallId(state: StreamItem[], callId: string): AgentToolCallItem | undefined {
   return state.find(
     (item): item is AgentToolCallItem =>
@@ -693,6 +708,27 @@ describe("stream reducer canonical tool calls", () => {
     assert.strictEqual(todos.items[1]?.completed, true);
   });
 
+  it("preserves compaction trigger when completed update replaces loading marker", () => {
+    const state = hydrateStreamState([
+      {
+        event: compactionTimeline("loading", "auto"),
+        timestamp: new Date("2025-01-01T10:50:00Z"),
+      },
+      {
+        event: compactionTimeline("completed"),
+        timestamp: new Date("2025-01-01T10:50:01Z"),
+      },
+    ]);
+
+    const compactions = state.filter(
+      (item): item is Extract<StreamItem, { kind: "compaction" }> => item.kind === "compaction",
+    );
+
+    assert.strictEqual(compactions.length, 1);
+    assert.strictEqual(compactions[0].status, "completed");
+    assert.strictEqual(compactions[0].trigger, "auto");
+  });
+
   it("renders Claude TodoWrite as todo_list and suppresses tool call badge", () => {
     const state = hydrateStreamState([
       {
diff --git a/packages/app/src/types/stream.ts b/packages/app/src/types/stream.ts
index 44bfa2e35..c67e0d0ed 100644
--- a/packages/app/src/types/stream.ts
+++ b/packages/app/src/types/stream.ts
@@ -726,8 +726,8 @@ function reduceTimelineCompaction(
       const updated: CompactionItem = {
         ...existing,
         status: "completed",
-        trigger: item.trigger,
-        preTokens: item.preTokens,
+        trigger: item.trigger ?? existing.trigger,
+        preTokens: item.preTokens ?? existing.preTokens,
       };
       return [...state.slice(0, loadingIdx), updated, ...state.slice(loadingIdx + 1)];
     }
diff --git a/packages/server/src/server/agent/providers/pi/agent.test.ts b/packages/server/src/server/agent/providers/pi/agent.test.ts
index 5b4eb5838..6866df671 100644
--- a/packages/server/src/server/agent/providers/pi/agent.test.ts
+++ b/packages/server/src/server/agent/providers/pi/agent.test.ts
@@ -2,7 +2,7 @@ import { closeSync, existsSync, fstatSync, openSync, readSync } from "node:fs";
 import pino from "pino";
 import { describe, expect, test } from "vitest";
 
-import type { AgentSessionConfig, AgentStreamEvent } from "../../agent-sdk-types.js";
+import type { AgentSession, AgentSessionConfig, AgentStreamEvent } from "../../agent-sdk-types.js";
 import { PiRpcAgentClient, PiRpcAgentSession, transformPiModels } from "./agent.js";
 import { FakePi } from "./test-utils/fake-pi.js";
 
@@ -693,12 +693,202 @@ describe("PiRpcAgentClient", () => {
     ];
 
     await expect(session.listCommands()).resolves.toEqual([
+      {
+        name: "compact",
+        description: "Manually compact the session context",
+        argumentHint: "[instructions]",
+      },
+      {
+        name: "autocompact",
+        description: "Toggle automatic context compaction",
+        argumentHint: "[on|off|toggle]",
+      },
       { name: "review", description: "Review changes", argumentHint: "" },
       { name: "fix-tests", description: "Fix tests", argumentHint: "" },
       { name: "skill:docs", description: "Read docs", argumentHint: "" },
     ]);
   });
 
+  test("lists Pi compact even when RPC get_commands omits built-in slash commands", async () => {
+    const { pi, session } = await createSession();
+    pi.latestSession().commands = [
+      { name: "review", description: "Review changes", source: "extension" },
+    ];
+
+    await expect(session.listCommands()).resolves.toContainEqual({
+      name: "compact",
+      description: "Manually compact the session context",
+      argumentHint: "[instructions]",
+    });
+    await expect(session.listCommands()).resolves.toContainEqual({
+      name: "autocompact",
+      description: "Toggle automatic context compaction",
+      argumentHint: "[on|off|toggle]",
+    });
+  });
+
+  test("preserves known argument hints when RPC get_commands returns built-in slash commands", async () => {
+    const { pi, session } = await createSession();
+    pi.latestSession().commands = [
+      { name: "compact", description: "Compact from RPC", source: "extension" },
+      { name: "autocompact", description: "Auto compact from RPC", source: "extension" },
+    ];
+
+    await expect(session.listCommands()).resolves.toEqual([
+      {
+        name: "compact",
+        description: "Compact from RPC",
+        argumentHint: "[instructions]",
+      },
+      {
+        name: "autocompact",
+        description: "Auto compact from RPC",
+        argumentHint: "[on|off|toggle]",
+      },
+    ]);
+  });
+
+  test("executes Pi compact through RPC instead of prompt text", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/compact focus on tests");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(fakeSession.compactRequests).toEqual([{ customInstructions: "focus on tests" }]);
+    expect(fakeSession.prompts).toEqual([]);
+    expect(events).toEqual([
+      {
+        type: "timeline",
+        provider: "pi",
+        item: { type: "compaction", status: "loading", trigger: "manual" },
+      },
+      {
+        type: "timeline",
+        provider: "pi",
+        item: { type: "compaction", status: "completed", trigger: "manual" },
+      },
+    ]);
+  });
+
+  test("closes Pi compact loading marker when RPC rejects after compaction starts", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    fakeSession.emitCompactEnd = false;
+    fakeSession.compactError = new Error("summarizer failed");
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/compact");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(events).toEqual([
+      {
+        type: "timeline",
+        provider: "pi",
+        item: { type: "compaction", status: "loading", trigger: "manual" },
+      },
+      {
+        type: "timeline",
+        provider: "pi",
+        item: { type: "compaction", status: "completed", trigger: "manual" },
+      },
+      {
+        type: "timeline",
+        provider: "pi",
+        item: {
+          type: "assistant_message",
+          text: "[Error] Failed to compact context: summarizer failed",
+        },
+      },
+    ]);
+  });
+
+  test("executes Pi autocompact through RPC instead of prompt text", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/autocompact off");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(fakeSession.setAutoCompactionRequests).toEqual([false]);
+    expect(fakeSession.prompts).toEqual([]);
+    expect(events).toEqual([
+      {
+        type: "timeline",
+        provider: "pi",
+        item: { type: "assistant_message", text: "Auto-compaction disabled." },
+      },
+    ]);
+  });
+
+  test("rejects unknown Pi autocompact mode instead of toggling", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/autocompact banana");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(fakeSession.setAutoCompactionRequests).toEqual([]);
+    expect(events).toEqual([
+      {
+        type: "timeline",
+        provider: "pi",
+        item: {
+          type: "assistant_message",
+          text: "[Error] Usage: /autocompact [on|off|toggle]",
+        },
+      },
+    ]);
+  });
+
+  test("toggles Pi autocompact through current RPC state", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    fakeSession.state.autoCompactionEnabled = false;
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/autocompact");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(fakeSession.setAutoCompactionRequests).toEqual([true]);
+    expect(events).toContainEqual({
+      type: "timeline",
+      provider: "pi",
+      item: { type: "assistant_message", text: "Auto-compaction enabled." },
+    });
+  });
+
+  test("rejects Pi autocompact toggle when current RPC state is unavailable", async () => {
+    const { pi, session } = await createSession();
+    const fakeSession = pi.latestSession();
+    delete fakeSession.state.autoCompactionEnabled;
+    const handler = (session as AgentSession).tryHandleOutOfBand?.("/autocompact");
+    const events: AgentStreamEvent[] = [];
+
+    expect(handler).not.toBeNull();
+    await handler?.run({ emit: (event) => events.push(event) });
+
+    expect(fakeSession.setAutoCompactionRequests).toEqual([]);
+    expect(events).toEqual([
+      {
+        type: "timeline",
+        provider: "pi",
+        item: {
+          type: "assistant_message",
+          text: "[Error] Auto-compaction state is unavailable. Use /autocompact on or /autocompact off.",
+        },
+      },
+    ]);
+  });
+
   test("rewinds conversation through the Pi tree navigation bridge", async () => {
     const { pi, session, events } = await createSession();
     pi.latestSession().capturedUserEntries = [
diff --git a/packages/server/src/server/agent/providers/pi/agent.ts b/packages/server/src/server/agent/providers/pi/agent.ts
index b76ab5c7b..e07176a33 100644
--- a/packages/server/src/server/agent/providers/pi/agent.ts
+++ b/packages/server/src/server/agent/providers/pi/agent.ts
@@ -86,6 +86,19 @@ const QUESTION_COMMENT_HEADER = "Comment";
 const PI_ASK_USER_FREEFORM_SENTINEL = "✏️ Type custom response...";
 const COMBINED_ASK_USER_METADATA = "ask_user_select_optional_comment";
 
+const PI_HANDLED_BUILTIN_SLASH_COMMANDS: AgentSlashCommand[] = [
+  {
+    name: "compact",
+    description: "Manually compact the session context",
+    argumentHint: "[instructions]",
+  },
+  {
+    name: "autocompact",
+    description: "Toggle automatic context compaction",
+    argumentHint: "[on|off|toggle]",
+  },
+];
+
 const PI_CAPABILITIES: AgentCapabilityFlags = {
   supportsStreaming: true,
   supportsSessionPersistence: true,
@@ -205,6 +218,13 @@ interface ExtensionUiMappingOptions {
   allowFreeform?: boolean;
 }
 
+interface PiSlashCommandInvocation {
+  commandName: string;
+  args?: string;
+}
+
+type AutoCompactMode = boolean | "toggle" | "unknown";
+
 function normalizePiModelLabel(label: string): string {
   return label.trim().replace(/[_\s]+/g, " ");
 }
@@ -247,6 +267,20 @@ function normalizePiThinkingOption(value: string | null | undefined): PiThinking
   return isPiThinkingLevel(value) ? value : null;
 }
 
+function parseAutoCompactMode(value: string | undefined): AutoCompactMode {
+  const mode = (value ?? "toggle").trim().toLowerCase();
+  if (mode === "on" || mode === "true" || mode === "enable" || mode === "enabled") {
+    return true;
+  }
+  if (mode === "off" || mode === "false" || mode === "disable" || mode === "disabled") {
+    return false;
+  }
+  if (mode === "toggle") {
+    return "toggle";
+  }
+  return "unknown";
+}
+
 function mapThinkingOption(option: (typeof PI_THINKING_OPTIONS)[number]) {
   const mappedOption = {
     id: option.id,
@@ -922,6 +956,9 @@ export class PiRpcAgentSession implements AgentSession {
   private readonly seenUserEntryIds = new Set<string>();
   private readonly pendingUserMessages: PendingPiUserMessage[] = [];
   private readonly pendingExtensionResults = new Map<string, PendingExtensionResult>();
+  private outOfBandCompactionEmit: ((event: AgentStreamEvent) => void) | null = null;
+  private outOfBandCompactionStarted = false;
+  private outOfBandCompactionCompleted = false;
   private state: PiSessionState;
   private closed = false;
 
@@ -1127,11 +1164,46 @@ export class PiRpcAgentSession implements AgentSession {
 
   async listCommands(): Promise<AgentSlashCommand[]> {
     const commands = await this.runtimeSession.getCommands();
-    return commands.map((command) => ({
-      name: command.name,
-      description: command.description ?? command.source,
-      argumentHint: "",
-    }));
+    const mappedCommands = new Map<string, AgentSlashCommand>(
+      PI_HANDLED_BUILTIN_SLASH_COMMANDS.map((command) => [command.name, { ...command }]),
+    );
+    for (const command of commands) {
+      const knownCommand = mappedCommands.get(command.name);
+      mappedCommands.set(command.name, {
+        name: command.name,
+        description: command.description ?? command.source,
+        argumentHint: knownCommand?.argumentHint ?? "",
+      });
+    }
+    return [...mappedCommands.values()];
+  }
+
+  tryHandleOutOfBand(
+    prompt: AgentPromptInput,
+  ): { run(ctx: { emit: (event: AgentStreamEvent) => void }): Promise<void> } | null {
+    if (typeof prompt !== "string") {
+      return null;
+    }
+    const parsed = this.parseSlashCommandInput(prompt);
+    if (!parsed) {
+      return null;
+    }
+    const commandName = parsed.commandName.toLowerCase();
+    if (commandName === "compact") {
+      return {
+        run: async ({ emit }) => {
+          await this.executeCompactCommand(parsed.args, emit);
+        },
+      };
+    }
+    if (commandName === "autocompact") {
+      return {
+        run: async ({ emit }) => {
+          await this.executeAutoCompactCommand(parsed.args, emit);
+        },
+      };
+    }
+    return null;
   }
 
   async setModel(modelId: string | null): Promise<void> {
@@ -1172,6 +1244,128 @@ export class PiRpcAgentSession implements AgentSession {
     return this.activeTurnId ?? undefined;
   }
 
+  private parseSlashCommandInput(text: string): PiSlashCommandInvocation | null {
+    const trimmed = text.trim();
+    if (!trimmed.startsWith("/") || trimmed.length <= 1) {
+      return null;
+    }
+    const withoutPrefix = trimmed.slice(1);
+    const firstWhitespaceIdx = withoutPrefix.search(/\s/);
+    const commandName =
+      firstWhitespaceIdx === -1 ? withoutPrefix : withoutPrefix.slice(0, firstWhitespaceIdx);
+    if (!commandName || commandName.includes("/")) {
+      return null;
+    }
+    const rawArgs =
+      firstWhitespaceIdx === -1 ? "" : withoutPrefix.slice(firstWhitespaceIdx + 1).trim();
+    return rawArgs.length > 0 ? { commandName, args: rawArgs } : { commandName };
+  }
+
+  private async executeCompactCommand(
+    customInstructions: string | undefined,
+    emit: (event: AgentStreamEvent) => void,
+  ): Promise<void> {
+    if (this.outOfBandCompactionEmit) {
+      throw new Error("A Pi compact command is already running");
+    }
+    this.outOfBandCompactionEmit = emit;
+    this.outOfBandCompactionStarted = false;
+    this.outOfBandCompactionCompleted = false;
+    try {
+      await this.runtimeSession.compact(customInstructions);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      if (
+        this.outOfBandCompactionEmit === emit &&
+        this.outOfBandCompactionStarted &&
+        !this.outOfBandCompactionCompleted
+      ) {
+        this.emitCompactionTimeline({
+          turnId: undefined,
+          item: {
+            type: "compaction",
+            status: "completed",
+            trigger: "manual",
+          },
+        });
+      }
+      emit({
+        type: "timeline",
+        provider: PI_PROVIDER,
+        item: {
+          type: "assistant_message",
+          text: `[Error] Failed to compact context: ${message}`,
+        },
+      });
+    } finally {
+      if (this.outOfBandCompactionEmit === emit && !this.outOfBandCompactionStarted) {
+        this.outOfBandCompactionEmit = null;
+        this.outOfBandCompactionStarted = false;
+        this.outOfBandCompactionCompleted = false;
+      }
+    }
+  }
+
+  private async executeAutoCompactCommand(
+    mode: string | undefined,
+    emit: (event: AgentStreamEvent) => void,
+  ): Promise<void> {
+    let enabled = parseAutoCompactMode(mode);
+    if (enabled === "unknown") {
+      emit({
+        type: "timeline",
+        provider: PI_PROVIDER,
+        item: {
+          type: "assistant_message",
+          text: "[Error] Usage: /autocompact [on|off|toggle]",
+        },
+      });
+      return;
+    }
+    if (enabled === "toggle") {
+      const state = await this.runtimeSession.getState();
+      if (typeof state.autoCompactionEnabled !== "boolean") {
+        emit({
+          type: "timeline",
+          provider: PI_PROVIDER,
+          item: {
+            type: "assistant_message",
+            text: "[Error] Auto-compaction state is unavailable. Use /autocompact on or /autocompact off.",
+          },
+        });
+        return;
+      }
+      enabled = !state.autoCompactionEnabled;
+    }
+
+    try {
+      await this.runtimeSession.setAutoCompaction(enabled);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      emit({
+        type: "timeline",
+        provider: PI_PROVIDER,
+        item: {
+          type: "assistant_message",
+          text: `[Error] Failed to set auto-compaction: ${message}`,
+        },
+      });
+      return;
+    }
+    this.state = {
+      ...this.state,
+      autoCompactionEnabled: enabled,
+    };
+    emit({
+      type: "timeline",
+      provider: PI_PROVIDER,
+      item: {
+        type: "assistant_message",
+        text: `Auto-compaction ${enabled ? "enabled" : "disabled"}.`,
+      },
+    });
+  }
+
   private async requestEntryCapture(reason: string): Promise<void> {
     const requestId = randomUUID();
     const resultPromise = this.waitForExtensionResult(requestId);
@@ -1433,9 +1627,7 @@ export class PiRpcAgentSession implements AgentSession {
         return;
       }
       case "compaction_start":
-        this.emit({
-          type: "timeline",
-          provider: PI_PROVIDER,
+        this.emitCompactionTimeline({
           turnId,
           item: {
             type: "compaction",
@@ -1445,13 +1637,12 @@ export class PiRpcAgentSession implements AgentSession {
         });
         return;
       case "compaction_end":
-        this.emit({
-          type: "timeline",
-          provider: PI_PROVIDER,
+        this.emitCompactionTimeline({
           turnId,
           item: {
             type: "compaction",
             status: "completed",
+            trigger: event.reason === "manual" ? "manual" : "auto",
           },
         });
         return;
@@ -1463,6 +1654,37 @@ export class PiRpcAgentSession implements AgentSession {
     }
   }
 
+  private emitCompactionTimeline(input: {
+    turnId: string | undefined;
+    item: Extract<AgentStreamEvent, { type: "timeline" }>["item"];
+  }): void {
+    const emitOutOfBand = this.outOfBandCompactionEmit;
+    if (emitOutOfBand && input.item.type === "compaction") {
+      if (input.item.status === "loading") {
+        this.outOfBandCompactionStarted = true;
+      }
+      if (input.item.status === "completed") {
+        this.outOfBandCompactionCompleted = true;
+      }
+    }
+    const event: AgentStreamEvent = {
+      type: "timeline",
+      provider: PI_PROVIDER,
+      ...(emitOutOfBand ? {} : { turnId: input.turnId }),
+      item: input.item,
+    };
+    if (emitOutOfBand) {
+      emitOutOfBand(event);
+      if (input.item.type === "compaction" && input.item.status === "completed") {
+        this.outOfBandCompactionEmit = null;
+        this.outOfBandCompactionStarted = false;
+        this.outOfBandCompactionCompleted = false;
+      }
+      return;
+    }
+    this.emit(event);
+  }
+
   private handleMessageUpdate(
     event: Extract<PiAgentSessionEvent, { type: "message_update" }>,
     turnId: string | undefined,
diff --git a/packages/server/src/server/agent/providers/pi/cli-runtime.ts b/packages/server/src/server/agent/providers/pi/cli-runtime.ts
index 84f8cbaf9..07af803a0 100644
--- a/packages/server/src/server/agent/providers/pi/cli-runtime.ts
+++ b/packages/server/src/server/agent/providers/pi/cli-runtime.ts
@@ -129,6 +129,17 @@ class PiCliRuntimeSession implements PiRuntimeSession {
     await this.request({ type: "prompt", message, ...(images?.length ? { images } : {}) });
   }
 
+  async compact(customInstructions?: string): Promise<void> {
+    await this.request({
+      type: "compact",
+      ...(customInstructions ? { customInstructions } : {}),
+    });
+  }
+
+  async setAutoCompaction(enabled: boolean): Promise<void> {
+    await this.request({ type: "set_auto_compaction", enabled });
+  }
+
   async abort(): Promise<void> {
     await this.request({ type: "abort" });
   }
diff --git a/packages/server/src/server/agent/providers/pi/rpc-types.ts b/packages/server/src/server/agent/providers/pi/rpc-types.ts
index 90f9aa4e1..b25a61659 100644
--- a/packages/server/src/server/agent/providers/pi/rpc-types.ts
+++ b/packages/server/src/server/agent/providers/pi/rpc-types.ts
@@ -79,6 +79,7 @@ export interface PiSessionState {
   thinkingLevel: PiThinkingLevel;
   isStreaming: boolean;
   isCompacting: boolean;
+  autoCompactionEnabled?: boolean;
   sessionFile?: string;
   sessionId: string;
   sessionName?: string;
@@ -111,6 +112,8 @@ export interface PiRpcSlashCommand {
 
 export type PiRpcCommand =
   | { id?: string; type: "prompt"; message: string; images?: PiImageContent[] }
+  | { id?: string; type: "compact"; customInstructions?: string }
+  | { id?: string; type: "set_auto_compaction"; enabled: boolean }
   | { id?: string; type: "abort" }
   | { id?: string; type: "get_state" }
   | { id?: string; type: "get_messages" }
diff --git a/packages/server/src/server/agent/providers/pi/runtime.ts b/packages/server/src/server/agent/providers/pi/runtime.ts
index e479c5894..0d813c12f 100644
--- a/packages/server/src/server/agent/providers/pi/runtime.ts
+++ b/packages/server/src/server/agent/providers/pi/runtime.ts
@@ -37,6 +37,8 @@ export interface PiRuntimeSession {
     message: string,
     images?: Array<{ type: "image"; data: string; mimeType: string }>,
   ): Promise<void>;
+  compact(customInstructions?: string): Promise<void>;
+  setAutoCompaction(enabled: boolean): Promise<void>;
   abort(): Promise<void>;
   getState(): Promise<PiSessionState>;
   getMessages(): Promise<PiAgentMessage[]>;
diff --git a/packages/server/src/server/agent/providers/pi/test-utils/fake-pi.ts b/packages/server/src/server/agent/providers/pi/test-utils/fake-pi.ts
index 08d92f201..53121c23a 100644
--- a/packages/server/src/server/agent/providers/pi/test-utils/fake-pi.ts
+++ b/packages/server/src/server/agent/providers/pi/test-utils/fake-pi.ts
@@ -51,6 +51,8 @@ export class FakePi implements PiRuntime {
 
 export class FakePiSession implements PiRuntimeSession {
   readonly prompts: Array<{ message: string; imageCount: number }> = [];
+  readonly compactRequests: Array<{ customInstructions?: string }> = [];
+  readonly setAutoCompactionRequests: boolean[] = [];
   readonly setModelRequests: Array<{ provider: string; modelId: string }> = [];
   readonly setThinkingLevelRequests: string[] = [];
   readonly treeNavigationRequests: string[] = [];
@@ -69,6 +71,8 @@ export class FakePiSession implements PiRuntimeSession {
     cost: 0,
   };
   commands: PiRpcSlashCommand[] = [];
+  compactError: Error | null = null;
+  emitCompactEnd = true;
   state: PiSessionState;
 
   private readonly subscribers = new Set<(event: PiRuntimeEvent) => void>();
@@ -79,6 +83,7 @@ export class FakePiSession implements PiRuntimeSession {
       thinkingLevel: "medium",
       isStreaming: false,
       isCompacting: false,
+      autoCompactionEnabled: true,
       sessionFile: launch.session ?? "/tmp/pi-session",
       sessionId: "pi-session-1",
       messageCount: 0,
@@ -102,6 +107,25 @@ export class FakePiSession implements PiRuntimeSession {
     this.handleEntryCaptureCommand(message);
   }
 
+  async compact(customInstructions?: string): Promise<void> {
+    this.compactRequests.push(customInstructions === undefined ? {} : { customInstructions });
+    this.emit({ type: "compaction_start", reason: "manual" });
+    if (this.emitCompactEnd) {
+      this.emit({ type: "compaction_end", reason: "manual" });
+    }
+    if (this.compactError) {
+      throw this.compactError;
+    }
+  }
+
+  async setAutoCompaction(enabled: boolean): Promise<void> {
+    this.setAutoCompactionRequests.push(enabled);
+    this.state = {
+      ...this.state,
+      autoCompactionEnabled: enabled,
+    };
+  }
+
   async abort(): Promise<void> {
     this.abortRequested = true;
   }
diff --git a/packages/server/src/server/daemon-e2e/pi.real.e2e.test.ts b/packages/server/src/server/daemon-e2e/pi.real.e2e.test.ts
index 8b2a9cd40..8140a6517 100644
--- a/packages/server/src/server/daemon-e2e/pi.real.e2e.test.ts
+++ b/packages/server/src/server/daemon-e2e/pi.real.e2e.test.ts
@@ -1,4 +1,4 @@
-import { existsSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { existsSync, mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import path from "node:path";
 import { randomUUID } from "node:crypto";
@@ -24,6 +24,7 @@ process.env.PASEO_SUPERVISED = "0";
 
 const PI_TEST_TIMEOUT_MS = 240_000;
 const PI_REAL_TEST_MODEL = getRealProviderConfig("pi").model;
+const PI_FREE_COMPACTION_TEST_MODEL = "openrouter/openai/gpt-oss-20b:free";
 
 type ToolCallItem = Extract<AgentTimelineItem, { type: "tool_call" }>;
 
@@ -31,6 +32,18 @@ function tmpCwd(prefix = "daemon-real-pi-"): string {
   return mkdtempSync(path.join(tmpdir(), prefix));
 }
 
+function sleep(ms: number): Promise<void> {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+function writePiCompactionSettings(
+  cwd: string,
+  compaction: { enabled: boolean; reserveTokens?: number; keepRecentTokens?: number },
+): void {
+  mkdirSync(path.join(cwd, ".pi"), { recursive: true });
+  writeFileSync(path.join(cwd, ".pi/settings.json"), JSON.stringify({ compaction }, null, 2));
+}
+
 function createPiClient(): AgentClient {
   return createRealProviderClient("pi", pino({ level: "silent" }));
 }
@@ -68,6 +81,27 @@ async function fetchCanonicalTimeline(
   return timeline.entries.map((entry) => entry.item);
 }
 
+async function waitForTimelineItem(
+  client: DaemonClient,
+  agentId: string,
+  predicate: (item: AgentTimelineItem) => boolean,
+  timeoutMs = PI_TEST_TIMEOUT_MS,
+): Promise<AgentTimelineItem> {
+  const deadline = Date.now() + timeoutMs;
+  let lastItems: AgentTimelineItem[] = [];
+  while (Date.now() < deadline) {
+    lastItems = await fetchCanonicalTimeline(client, agentId);
+    const item = lastItems.find(predicate);
+    if (item) {
+      return item;
+    }
+    await sleep(250);
+  }
+  throw new Error(
+    `Timed out waiting for Pi timeline item. Last timeline: ${JSON.stringify(lastItems)}`,
+  );
+}
+
 async function withConnectedPiDaemon(
   run: (context: { client: DaemonClient }) => Promise<void>,
 ): Promise<void> {
@@ -101,6 +135,200 @@ beforeEach((context) => {
   }
 });
 
+test(
+  "real Pi daemon lists Paseo-handled compact slash commands",
+  async () => {
+    const cwd = tmpCwd("pi-compact-commands-");
+
+    try {
+      await withConnectedPiDaemon(async ({ client }) => {
+        const agent = await client.createAgent({
+          cwd,
+          title: "pi-compact-commands",
+          provider: "pi",
+          model: PI_FREE_COMPACTION_TEST_MODEL,
+        });
+
+        const result = await client.listCommands(agent.id);
+        expect(result.commands).toEqual(
+          expect.arrayContaining([
+            expect.objectContaining({
+              name: "compact",
+              description: "Manually compact the session context",
+            }),
+            expect.objectContaining({
+              name: "autocompact",
+              description: "Toggle automatic context compaction",
+            }),
+          ]),
+        );
+      });
+    } finally {
+      rmSync(cwd, { recursive: true, force: true });
+    }
+  },
+  PI_TEST_TIMEOUT_MS,
+);
+
+test(
+  "real Pi daemon executes manual compact out-of-band instead of prompt text",
+  async () => {
+    const cwd = tmpCwd("pi-manual-compact-");
+
+    try {
+      writePiCompactionSettings(cwd, {
+        enabled: true,
+        keepRecentTokens: 1,
+      });
+
+      await withConnectedPiDaemon(async ({ client }) => {
+        const agent = await client.createAgent({
+          cwd,
+          title: "pi-manual-compact",
+          provider: "pi",
+          model: PI_FREE_COMPACTION_TEST_MODEL,
+        });
+
+        await client.sendMessage(agent.id, "Reply exactly: compact-ready");
+        const finish = await client.waitForFinish(agent.id, PI_TEST_TIMEOUT_MS);
+        expect(finish.status).toBe("idle");
+
+        await client.sendMessage(agent.id, "/compact summarize this e2e run");
+
+        await waitForTimelineItem(
+          client,
+          agent.id,
+          (item) => item.type === "compaction" && item.status === "completed",
+        );
+
+        const items = await fetchCanonicalTimeline(client, agent.id);
+        expect(items).toEqual(
+          expect.arrayContaining([
+            expect.objectContaining({
+              type: "compaction",
+              status: "loading",
+              trigger: "manual",
+            }),
+            expect.objectContaining({
+              type: "compaction",
+              status: "completed",
+            }),
+          ]),
+        );
+        expect(
+          items.some((item) => item.type === "user_message" && item.text.includes("/compact")),
+        ).toBe(false);
+        expect(
+          items.some(
+            (item) => item.type === "assistant_message" && item.text.includes("Failed to compact"),
+          ),
+        ).toBe(false);
+      });
+    } finally {
+      rmSync(cwd, { recursive: true, force: true });
+    }
+  },
+  PI_TEST_TIMEOUT_MS,
+);
+
+test(
+  "real Pi daemon toggles auto-compaction out-of-band instead of prompt text",
+  async () => {
+    const cwd = tmpCwd("pi-autocompact-toggle-");
+
+    try {
+      await withConnectedPiDaemon(async ({ client }) => {
+        const agent = await client.createAgent({
+          cwd,
+          title: "pi-autocompact-toggle",
+          provider: "pi",
+          model: PI_FREE_COMPACTION_TEST_MODEL,
+        });
+
+        await client.sendMessage(agent.id, "/autocompact off");
+        await waitForTimelineItem(
+          client,
+          agent.id,
+          (item) => item.type === "assistant_message" && item.text === "Auto-compaction disabled.",
+        );
+
+        await client.sendMessage(agent.id, "/autocompact");
+        await waitForTimelineItem(
+          client,
+          agent.id,
+          (item) => item.type === "assistant_message" && item.text === "Auto-compaction enabled.",
+        );
+
+        const items = await fetchCanonicalTimeline(client, agent.id);
+        expect(
+          items.some((item) => item.type === "user_message" && item.text.includes("/autocompact")),
+        ).toBe(false);
+      });
+    } finally {
+      rmSync(cwd, { recursive: true, force: true });
+    }
+  },
+  PI_TEST_TIMEOUT_MS,
+);
+
+test(
+  "real Pi daemon surfaces automatic threshold compaction events",
+  async () => {
+    const cwd = tmpCwd("pi-auto-compact-");
+
+    try {
+      writePiCompactionSettings(cwd, {
+        enabled: true,
+        reserveTokens: 126_000,
+        keepRecentTokens: 1,
+      });
+
+      await withConnectedPiDaemon(async ({ client }) => {
+        const agent = await client.createAgent({
+          cwd,
+          title: "pi-auto-compact",
+          provider: "pi",
+          model: PI_FREE_COMPACTION_TEST_MODEL,
+        });
+
+        await client.sendMessage(agent.id, "Reply exactly: auto-compact-ready");
+        const finish = await client.waitForFinish(agent.id, PI_TEST_TIMEOUT_MS);
+        expect(finish.status, JSON.stringify(finish)).toBe("idle");
+
+        await waitForTimelineItem(
+          client,
+          agent.id,
+          (item) => item.type === "compaction" && item.status === "completed",
+        );
+
+        const items = await fetchCanonicalTimeline(client, agent.id);
+        expect(items).toEqual(
+          expect.arrayContaining([
+            expect.objectContaining({
+              type: "compaction",
+              status: "loading",
+              trigger: "auto",
+            }),
+            expect.objectContaining({
+              type: "compaction",
+              status: "completed",
+            }),
+          ]),
+        );
+        expect(
+          items.some(
+            (item) =>
+              item.type === "assistant_message" && item.text.includes("Auto-compaction failed"),
+          ),
+        ).toBe(false);
+      });
+    } finally {
+      rmSync(cwd, { recursive: true, force: true });
+    }
+  },
+  PI_TEST_TIMEOUT_MS,
+);
+
 test(
   "bash tool call records completed shell detail and output",
   async () => {