fix(codex): end an interrupted turn's shell commands (#7525)

`turn/interrupt` ends a Codex turn and leaves the shell commands it started running: a
command the user just stopped runs on to its own end, alongside the next turn.

Once Codex accepts the interrupt, the provider now ends each command the interrupted turn
started that has not exited, by process id, with `thread/backgroundTerminals/terminate`,
and a turn Paseo starts waits for those calls before its `turn/start`.

- Attribution: `thread/backgroundTerminals/list` carries no turn, so the provider records
  each root-thread `commandExecution` process id under the turn of its `item/started`. A
  `completed` item drops its id; a `failed` one keeps it, because Codex reports an
  interrupted turn's still-running command as failed. A turn that ends any way but
  `interrupted` forgets its ids, so what an earlier turn left running on purpose is never
  ended. At most 16 turns are remembered.
- A late command: the turn keeps its accepted interrupt, so a command whose `item/started`
  arrives after Codex accepted the interrupt (one queued behind an earlier notification's
  conversion, for instance) is ended as soon as it is seen. Each process is terminated
  once, and a turn start waits for every pending sweep.
- It never sends `thread/backgroundTerminals/clean`, which ends every terminal on the
  thread. It ends nothing after an already-idle interrupt, nothing on a subagent's thread,
  and nothing after an interrupt of a turn Codex never identified.
- Bounds: each terminate times out after 2 s; a failure is logged
  (`provider.codex.interrupt.terminal_terminate_failed`) and fails nothing. `startTurn`
  waits at most the interrupt's bound plus one terminate's plus 500 ms.

Tests (codex-interrupted-turn-terminals.test.ts) drive a real CodexAppServerAgentSession
against the scripted app-server in codex/test-utils/fake-app-server.ts: exactly the
interrupted turn's processes are terminated, by id, and `clean` is never sent; a turn
Codex starts before acknowledging the interrupt keeps its commands; the next `turn/start`
waits for the terminates; a command announced after the interrupt was accepted is
terminated once and the next turn waits for both sweeps, whichever answers first; a
completed command is forgotten and a failed one kept; only the latest sixteen accepted
interrupts are kept; a failing or unanswered terminate does not block the next turn. The
harness waits for the interrupted turn's `turn_canceled` before it starts the next turn,
as a caller does: notifications are handled asynchronously, so the interrupt's answer can
arrive before the turn has ended.

Fixes #7522


Claude-Session: https://claude.ai/code/session_01Ay568T2kmtotoh23Dtzi5K

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

packages/server/src/server/agent/providers/codex-app-server-agent.ts

@@ -150,6 +150,15 @@ function isCodexAlreadyUnarchivedError(error: unknown, threadId: string): boolea
 
 const TURN_START_TIMEOUT_MS = 90 * 1000;
 const INTERRUPT_TIMEOUT_MS = 2_000;
+// `turn/interrupt` ends a turn but leaves the shell commands it started running.
+// Each terminate is bounded by the first constant. A turn start waits for the
+// interrupted turn's commands to end, at most the interrupt's own bound plus one
+// terminate's and a margin, so it gives up only when a request outlives its timeout.
+const INTERRUPTED_TURN_TERMINATE_TIMEOUT_MS = 2_000;
+const INTERRUPTED_TURN_CLEANUP_WAIT_MS =
+  INTERRUPT_TIMEOUT_MS + INTERRUPTED_TURN_TERMINATE_TIMEOUT_MS + 500;
+// Turns whose commands are remembered; older turns are forgotten first.
+const INTERRUPTED_TURN_TRACKED_TURNS = 16;
 const CODEX_PROVIDER = "codex" as const;
 // These native provider identities belong to Codex, not to an older custom
 // Paseo provider. Never include them in a custom provider's legacy import scan.
@@ -3476,6 +3485,14 @@ export class CodexAppServerAgentSession implements AgentSession {
   private pendingFileChangeOutputDeltas = new Map<string, string[]>();
   private pendingAssistantMessageBoundary = false;
   private terminalCommandByProcessId = new Map<string, string>();
+  // The root thread's still-running command process ids, keyed by the native turn that
+  // started them. Codex's `thread/backgroundTerminals/list` carries no turn, so
+  // `item/started` is the only record of which turn owns a process.
+  private terminalProcessIdsByTurnId = new Map<
+    string,
+    { processIds: Set<string>; terminatedProcessIds: Set<string>; interruptAccepted: boolean }
+  >();
+  private interruptedTurnCleanup: Promise<void> | null = null;
   private pendingUnlabeledTerminalInteractions = new Map<
     string,
     Array<{ callId: string; stdin: string | null }>
@@ -4431,6 +4448,9 @@ export class CodexAppServerAgentSession implements AgentSession {
         hasDeveloperInstructions: turnStart.hasDeveloperInstructions,
         hasCodexConfig: turnStart.hasCodexConfig,
       });
+      // The interrupted turn's commands end before this turn begins, so none of them
+      // outlives it into the new turn.
+      await this.waitForInterruptedTurnCleanup();
       if (pendingStart.cancelRequested) {
         throw new Error("Codex turn start was interrupted before reaching Codex");
       }
@@ -5036,15 +5056,27 @@ export class CodexAppServerAgentSession implements AgentSession {
     if (!turnId || (foregroundTurnId && this.activeForegroundTurnId !== foregroundTurnId)) {
       throw new Error("Cannot interrupt Codex before turn/started identifies the active turn");
     }
+    const client = this.client;
+    const threadId = this.currentThreadId;
+    const interruptRequest = client.request(
+      "turn/interrupt",
+      {
+        threadId,
+        turnId,
+      },
+      INTERRUPT_TIMEOUT_MS,
+    );
+    // Once Codex accepts the interrupt, end the commands this turn started. Registered
+    // before the await, so a turn start racing this interrupt waits for it. An already-idle
+    // turn was not interrupted, and what it left running stays.
+    this.trackInterruptedTurnCleanup(
+      interruptRequest.then(
+        () => this.endInterruptedTurnProcesses(client, threadId, turnId),
+        () => undefined,
+      ),
+    );
     try {
-      await this.client.request(
-        "turn/interrupt",
-        {
-          threadId: this.currentThreadId,
-          turnId,
-        },
-        INTERRUPT_TIMEOUT_MS,
-      );
+      await interruptRequest;
     } catch (error) {
       if (!isCodexAlreadyIdleInterrupt(error)) {
         throw error;
@@ -5085,6 +5117,137 @@ export class CodexAppServerAgentSession implements AgentSession {
     return !this.client.hasPendingRequests();
   }
 
+  // Remember which turn started a command, so an interrupt ends that turn's commands and
+  // no other turn's. Only the root thread's: a subagent's commands live on its own thread.
+  // A command that starts after its turn's interrupt was accepted is ended as soon as it
+  // is seen.
+  private recordTurnTerminalProcess(
+    parsed: Extract<ParsedCodexNotification, { kind: "item_started" | "item_completed" }>,
+  ): void {
+    const processId = parsed.item.processId;
+    if (
+      parsed.source !== "item" ||
+      !parsed.turnId ||
+      !parsed.threadId ||
+      parsed.threadId !== this.currentThreadId ||
+      typeof processId !== "string" ||
+      !processId ||
+      normalizeCodexThreadItemType(
+        typeof parsed.item.type === "string" ? parsed.item.type : undefined,
+      ) !== "commandExecution"
+    ) {
+      return;
+    }
+    const record = this.terminalProcessIdsByTurnId.get(parsed.turnId);
+    if (parsed.kind === "item_completed") {
+      // Only a completed command has exited. A failed one can still be running:
+      // Codex reports an interrupted turn's live command as failed.
+      if (parsed.item.status === "completed") record?.processIds.delete(processId);
+      return;
+    }
+    const current = record ?? this.getTurnTerminalRecord(parsed.turnId);
+    current.processIds.add(processId);
+    if (current.interruptAccepted && this.client) {
+      this.trackInterruptedTurnCleanup(
+        this.endInterruptedTurnProcesses(this.client, parsed.threadId, parsed.turnId),
+      );
+    }
+  }
+
+  // An accepted interrupt needs a record even before any of its turn's commands is seen:
+  // an `item/started` can still be queued behind an earlier notification's conversion.
+  private getTurnTerminalRecord(turnId: string) {
+    const existing = this.terminalProcessIdsByTurnId.get(turnId);
+    if (existing) return existing;
+    const record = {
+      processIds: new Set<string>(),
+      terminatedProcessIds: new Set<string>(),
+      interruptAccepted: false,
+    };
+    this.terminalProcessIdsByTurnId.set(turnId, record);
+    for (const oldestTurnId of this.terminalProcessIdsByTurnId.keys()) {
+      if (this.terminalProcessIdsByTurnId.size <= INTERRUPTED_TURN_TRACKED_TURNS) break;
+      this.terminalProcessIdsByTurnId.delete(oldestTurnId);
+    }
+    return record;
+  }
+
+  // A later sweep joins the pending one, so a turn start waits for both.
+  private trackInterruptedTurnCleanup(cleanup: Promise<void>): void {
+    const tracked = Promise.all([this.interruptedTurnCleanup, cleanup])
+      .then(() => undefined)
+      .finally(() => {
+        if (this.interruptedTurnCleanup === tracked) this.interruptedTurnCleanup = null;
+      });
+    this.interruptedTurnCleanup = tracked;
+  }
+
+  // Terminate each process the interrupted turn started, by its own id, once each.
+  // `thread/backgroundTerminals/clean` is never used: it ends every terminal on the thread,
+  // an earlier turn's included. A process already gone answers `terminated: false`. Never
+  // rejects; failures are logged.
+  private async endInterruptedTurnProcesses(
+    client: CodexAppServerClient,
+    threadId: string | null,
+    turnId: string,
+  ): Promise<void> {
+    if (!threadId) return;
+    const record = this.getTurnTerminalRecord(turnId);
+    record.interruptAccepted = true;
+    const processIds = [...record.processIds].filter(
+      (processId) => !record.terminatedProcessIds.has(processId),
+    );
+    for (const processId of processIds) record.terminatedProcessIds.add(processId);
+    const logContext = { agentId: this.agentId, provider: CODEX_PROVIDER, threadId, turnId };
+    await Promise.all(
+      processIds.map(async (processId) => {
+        try {
+          const response = await client.request(
+            "thread/backgroundTerminals/terminate",
+            { threadId, processId },
+            INTERRUPTED_TURN_TERMINATE_TIMEOUT_MS,
+          );
+          this.logger.info(
+            { ...logContext, processId, terminated: toObjectRecord(response)?.terminated ?? null },
+            "provider.codex.interrupt.terminal_terminated",
+          );
+        } catch (error) {
+          this.logger.warn(
+            { ...logContext, processId, err: error },
+            "provider.codex.interrupt.terminal_terminate_failed",
+          );
+        }
+      }),
+    );
+  }
+
+  // A new turn starts only after every pending sweep of interrupted turns' commands has
+  // ended, or after the bound, whichever is first.
+  private async waitForInterruptedTurnCleanup(): Promise<void> {
+    if (!this.interruptedTurnCleanup) return;
+    let timer: ReturnType<typeof setTimeout> | undefined;
+    const timedOut = await Promise.race([
+      (async () => {
+        while (this.interruptedTurnCleanup) await this.interruptedTurnCleanup;
+        return false;
+      })(),
+      new Promise<boolean>((resolve) => {
+        timer = setTimeout(() => resolve(true), INTERRUPTED_TURN_CLEANUP_WAIT_MS);
+      }),
+    ]);
+    clearTimeout(timer);
+    if (timedOut) {
+      this.logger.warn(
+        {
+          agentId: this.agentId,
+          provider: CODEX_PROVIDER,
+          waitMs: INTERRUPTED_TURN_CLEANUP_WAIT_MS,
+        },
+        "provider.codex.interrupt.terminal_cleanup_timed_out",
+      );
+    }
+  }
+
   async close(): Promise<void> {
     this.closed = true;
     this.clearPendingPermissions();
@@ -6209,6 +6372,11 @@ export class CodexAppServerAgentSession implements AgentSession {
       return;
     }
     this.completePendingRootCompactions();
+    // What a turn that was not interrupted leaves running, it left on purpose; no later
+    // interrupt may end it.
+    if (parsed.status !== "interrupted" && this.currentTurnId) {
+      this.terminalProcessIdsByTurnId.delete(this.currentTurnId);
+    }
     if (parsed.status === "failed") {
       this.emitEvent({
         type: "turn_failed",
@@ -6613,6 +6781,7 @@ export class CodexAppServerAgentSession implements AgentSession {
   private async handleItemCompletedNotification(
     parsed: Extract<ParsedCodexNotification, { kind: "item_completed" }>,
   ): Promise<void> {
+    this.recordTurnTerminalProcess(parsed);
     // Codex emits mirrored lifecycle notifications via both `codex/event/item_*`
     // and canonical `item/*`. Render ordinary items only from the canonical
     // channel, but accept a legacy-only child announcement so it can establish
@@ -6775,6 +6944,7 @@ export class CodexAppServerAgentSession implements AgentSession {
   private async handleItemStartedNotification(
     parsed: Extract<ParsedCodexNotification, { kind: "item_started" }>,
   ): Promise<void> {
+    this.recordTurnTerminalProcess(parsed);
     if (shouldIgnoreMirroredLifecycleItem(parsed.source, parsed.item)) {
       return;
     }

packages/server/src/server/agent/providers/codex-interrupted-turn-terminals.test.ts

@@ -0,0 +1,374 @@
+import { afterEach, describe, expect, test, vi } from "vitest";
+
+import type { AgentSession } from "../agent-sdk-types.js";
+import { createTestLogger } from "../../../test-utils/test-logger.js";
+import { CodexAppServerAgentSession } from "./codex-app-server-agent.js";
+import {
+  createFakeCodexAppServer,
+  type FakeCodexAppServer,
+  waitForNextEvent,
+  waitForTimelineToolCall,
+} from "./codex/test-utils/fake-app-server.js";
+
+const THREAD = "thread-1";
+const TERMINATE = "thread/backgroundTerminals/terminate";
+
+type Handler = (params: unknown) => unknown;
+
+function deferred<T = void>() {
+  let resolve!: (value: T) => void;
+  const promise = new Promise<T>((resolvePromise) => {
+    resolve = resolvePromise;
+  });
+  return { promise, resolve };
+}
+
+function paramsOf(value: unknown): Record<string, unknown> {
+  return value && typeof value === "object" ? (value as Record<string, unknown>) : {};
+}
+
+let sessions: AgentSession[] = [];
+
+afterEach(async () => {
+  for (const session of sessions) await session.close().catch(() => undefined);
+  sessions = [];
+});
+
+/**
+ * A Codex app-server whose interrupt ends the turn the way Codex does: an `interrupted`
+ * turn completion, then the response. `terminate` answers per process.
+ */
+function createHarness(
+  options: {
+    terminate?: (processId: string) => unknown;
+    interruptResponse?: (completeTurn: () => void) => unknown;
+  } = {},
+) {
+  const handlers: Record<string, Handler> = {
+    "turn/interrupt": () => {
+      const completeTurn = () =>
+        appServer.completeTurn({ threadId: THREAD, status: "interrupted" });
+      if (options.interruptResponse) return options.interruptResponse(completeTurn);
+      completeTurn();
+      return {};
+    },
+    [TERMINATE]: (params) =>
+      options.terminate?.(String(paramsOf(params).processId)) ?? { terminated: true },
+  };
+  const appServer: FakeCodexAppServer = createFakeCodexAppServer(handlers);
+  const session = new CodexAppServerAgentSession(
+    {
+      provider: "codex",
+      cwd: "/workspace/project",
+      modeId: "auto",
+      model: "gpt-5.4",
+    },
+    null,
+    createTestLogger(),
+    async () => appServer.child,
+  );
+  sessions.push(session);
+
+  function requests(method: string): Record<string, unknown>[] {
+    return appServer
+      .requests()
+      .filter((message) => message.method === method && "id" in message)
+      .map((message) => paramsOf(message.params));
+  }
+
+  function terminated(): string[] {
+    return requests(TERMINATE)
+      .map((params) => String(params.processId))
+      .sort();
+  }
+
+  // Starts a turn and lets Codex identify it as `nativeTurnId`.
+  async function startTurn(prompt: string, nativeTurnId: string): Promise<void> {
+    const before = requests("turn/start").length;
+    const started = session.startTurn(prompt);
+    await vi.waitFor(() => expect(requests("turn/start")).toHaveLength(before + 1), {
+      timeout: 5_000,
+    });
+    const turnStarted = waitForNextEvent(session, "turn_started");
+    appServer.startsTurn({ threadId: THREAD, turnId: nativeTurnId });
+    await started;
+    await turnStarted;
+  }
+
+  async function runsCommand(params: { turnId: string; processId: string }): Promise<void> {
+    const itemId = `exec-${params.processId}`;
+    const shown = waitForTimelineToolCall(session, itemId);
+    appServer.startsTerminalCommand({
+      threadId: THREAD,
+      turnId: params.turnId,
+      itemId,
+      processId: params.processId,
+      command: `sleep ${params.processId}`,
+    });
+    await shown;
+  }
+
+  async function completesTurn(): Promise<void> {
+    const completed = waitForNextEvent(session, "turn_completed");
+    appServer.completeTurn({ threadId: THREAD });
+    await completed;
+  }
+
+  // Interrupts the running turn and waits for the session to report it canceled, as a
+  // caller does before it starts the next turn: Codex notifications are handled in order
+  // but asynchronously, so the interrupt's answer can arrive before the turn has ended.
+  async function interrupts(): Promise<void> {
+    const canceled = waitForNextEvent(session, "turn_canceled");
+    await session.interrupt();
+    await canceled;
+  }
+
+  return {
+    appServer,
+    session,
+    requests,
+    terminated,
+    startTurn,
+    runsCommand,
+    completesTurn,
+    interrupts,
+  };
+}
+
+// Turn A leaves a server running on purpose and completes. Turn B starts two
+// commands, and a subagent on its own thread starts a third, then B is interrupted.
+async function interruptTurnB(harness: ReturnType<typeof createHarness>): Promise<void> {
+  await harness.startTurn("start a server", "native-A");
+  await harness.runsCommand({ turnId: "native-A", processId: "101" });
+  await harness.completesTurn();
+
+  await harness.startTurn("run two commands", "native-B");
+  await harness.runsCommand({ turnId: "native-B", processId: "201" });
+  // A subagent thread's command shows no row here; the next command's row shows it
+  // was read, because notifications are read in order.
+  harness.appServer.startsTerminalCommand({
+    threadId: "child-thread",
+    turnId: "native-B",
+    itemId: "exec-209",
+    processId: "209",
+    command: "sleep 209",
+  });
+  await harness.runsCommand({ turnId: "native-B", processId: "202" });
+  await harness.interrupts();
+}
+
+describe("an interrupted Codex turn's commands end before the next turn", () => {
+  test("terminates exactly the processes the interrupted turn started, by id, and never cleans", async () => {
+    const harness = createHarness();
+    await interruptTurnB(harness);
+    await harness.startTurn("correction", "native-C");
+
+    expect(harness.terminated()).toEqual(["201", "202"]);
+    expect(harness.requests(TERMINATE).every((params) => params.threadId === THREAD)).toBe(true);
+    // `clean` would end every terminal on the thread, an earlier turn's included.
+    expect(
+      harness.appServer
+        .requests()
+        .filter((message) => String(message.method).startsWith("thread/backgroundTerminals/"))
+        .map((message) => message.method),
+    ).toEqual([TERMINATE, TERMINATE]);
+    harness.appServer.assertNoErrors();
+  });
+
+  test("leaves the next turn's commands running when Codex starts that turn before acknowledging the interrupt", async () => {
+    const acknowledge = deferred();
+    const harness = createHarness({
+      // Codex ends B, starts a turn of its own (a goal continuation), and only then
+      // answers the interrupt.
+      interruptResponse: (completeTurn) => {
+        completeTurn();
+        return acknowledge.promise.then(() => ({}));
+      },
+    });
+    await harness.startTurn("run two commands", "native-B");
+    await harness.runsCommand({ turnId: "native-B", processId: "201" });
+    await harness.runsCommand({ turnId: "native-B", processId: "202" });
+    const interrupting = harness.session.interrupt();
+    await vi.waitFor(() => expect(harness.requests("turn/interrupt")).toHaveLength(1));
+    const autonomousTurn = waitForNextEvent(harness.session, "turn_started");
+    harness.appServer.startsTurn({ threadId: THREAD, turnId: "native-C" });
+    await autonomousTurn;
+    await harness.runsCommand({ turnId: "native-C", processId: "301" });
+
+    acknowledge.resolve();
+    await interrupting;
+    await vi.waitFor(() => expect(harness.terminated()).toEqual(["201", "202"]));
+    await new Promise((resolve) => setTimeout(resolve, 50));
+    expect(harness.terminated()).toEqual(["201", "202"]);
+  });
+
+  test("sends the next turn/start only after the terminates are answered", async () => {
+    const answer = deferred();
+    const harness = createHarness({
+      terminate: () => answer.promise.then(() => ({ terminated: true })),
+    });
+    await interruptTurnB(harness);
+    const next = harness.startTurn("correction", "native-C");
+    await vi.waitFor(() => expect(harness.terminated()).toEqual(["201", "202"]));
+    await new Promise((resolve) => setTimeout(resolve, 200));
+    expect(harness.requests("turn/start")).toHaveLength(2);
+
+    answer.resolve();
+    await next;
+    expect(harness.requests("turn/start")).toHaveLength(3);
+  });
+
+  test.each(["initial", "late"] as const)(
+    "tracks both cleanup sweeps when the %s answer arrives first",
+    async (answeredFirst) => {
+      const first = deferred();
+      const second = deferred();
+      const harness = createHarness({
+        terminate: (processId) =>
+          (processId === "201" ? first : second).promise.then(() => ({ terminated: true })),
+      });
+      await harness.startTurn("run commands", "native-B");
+      await harness.runsCommand({ turnId: "native-B", processId: "201" });
+      await harness.interrupts();
+      await vi.waitFor(() => expect(harness.terminated()).toEqual(["201"]));
+      const next = harness.startTurn("correction", "native-C");
+      await new Promise((resolve) => setTimeout(resolve, 100));
+      expect(harness.requests("turn/start")).toHaveLength(1);
+      // The next turn is already waiting when another process is announced.
+      harness.appServer.startsTerminalCommand({
+        threadId: THREAD,
+        turnId: "native-B",
+        itemId: "late-202",
+        processId: "202",
+        command: "sleep 202",
+      });
+      harness.appServer.startsTerminalCommand({
+        threadId: THREAD,
+        turnId: "native-B",
+        itemId: "duplicate-202",
+        processId: "202",
+        command: "sleep 202",
+      });
+      await vi.waitFor(() => expect(harness.terminated()).toEqual(["201", "202"]));
+      (answeredFirst === "initial" ? first : second).resolve();
+      await new Promise((resolve) => setTimeout(resolve, 100));
+      expect(harness.requests("turn/start")).toHaveLength(1);
+      (answeredFirst === "initial" ? second : first).resolve();
+      await next;
+      expect(harness.terminated()).toEqual(["201", "202"]);
+      // Accepted state survives the completed sweep and a newer foreground turn.
+      harness.appServer.startsTerminalCommand({
+        threadId: THREAD,
+        turnId: "native-B",
+        itemId: "late-203",
+        processId: "203",
+        command: "sleep 203",
+      });
+      await vi.waitFor(() => expect(harness.terminated()).toEqual(["201", "202", "203"]));
+      harness.appServer.assertNoErrors();
+    },
+  );
+
+  test("keeps the first sweep pending when a late sweep answers before the next start", async () => {
+    const first = deferred();
+    const harness = createHarness({
+      terminate: (processId) =>
+        processId === "201"
+          ? first.promise.then(() => ({ terminated: true }))
+          : { terminated: true },
+    });
+    await harness.startTurn("run commands", "native-B");
+    await harness.runsCommand({ turnId: "native-B", processId: "201" });
+    await harness.interrupts();
+    harness.appServer.startsTerminalCommand({
+      threadId: THREAD,
+      turnId: "native-B",
+      itemId: "late-202",
+      processId: "202",
+      command: "sleep 202",
+    });
+    await vi.waitFor(() => expect(harness.terminated()).toEqual(["201", "202"]));
+    const next = harness.startTurn("correction", "native-C");
+    await new Promise((resolve) => setTimeout(resolve, 100));
+    expect(harness.requests("turn/start")).toHaveLength(1);
+    first.resolve();
+    await next;
+    harness.appServer.assertNoErrors();
+  });
+
+  test("forgets completed commands but retains failed commands at interrupt", async () => {
+    const harness = createHarness();
+    await harness.startTurn("run commands", "native-B");
+    for (const processId of ["201", "202"]) {
+      await harness.runsCommand({ turnId: "native-B", processId });
+      harness.appServer.child.stdout.write(
+        JSON.stringify({
+          method: "item/completed",
+          params: {
+            threadId: THREAD,
+            turnId: "native-B",
+            item: {
+              id: `exec-${processId}`,
+              type: "commandExecution",
+              processId,
+              command: `sleep ${processId}`,
+              status: processId === "201" ? "completed" : "failed",
+              exitCode: processId === "201" ? 0 : null,
+            },
+          },
+        }) + "\n",
+      );
+    }
+    // A following command's row is a barrier for both completion handlers.
+    await harness.runsCommand({ turnId: "native-B", processId: "203" });
+    await harness.interrupts();
+    await harness.startTurn("correction", "native-C");
+    expect(harness.terminated()).toEqual(["202", "203"]);
+    harness.appServer.assertNoErrors();
+  });
+
+  test("retains accepted interrupts for only the latest sixteen turns", async () => {
+    const harness = createHarness();
+    for (let index = 0; index < 17; index++) {
+      await harness.startTurn("run a command", `native-${index}`);
+      await harness.interrupts();
+    }
+    await harness.startTurn("correction", "native-current");
+    harness.appServer.startsTerminalCommand({
+      threadId: THREAD,
+      turnId: "native-0",
+      itemId: "evicted-201",
+      processId: "201",
+      command: "sleep 201",
+    });
+    harness.appServer.startsTerminalCommand({
+      threadId: THREAD,
+      turnId: "native-16",
+      itemId: "retained-202",
+      processId: "202",
+      command: "sleep 202",
+    });
+    await harness.runsCommand({ turnId: "native-current", processId: "301" });
+    expect(harness.terminated()).toEqual(["202"]);
+    harness.appServer.assertNoErrors();
+  });
+
+  test("a failing or unanswered terminate does not block or fail the next turn", async () => {
+    const harness = createHarness({
+      // 201 is refused while the next turn waits; 202 is never answered.
+      terminate: (processId) =>
+        processId === "201"
+          ? new Promise((resolve) => setTimeout(resolve, 300)).then(() => ({
+              __jsonRpcError: { code: -32600, message: "invalid background terminal process id" },
+            }))
+          : new Promise(() => {}),
+    });
+    await interruptTurnB(harness);
+    const startedAt = Date.now();
+    await harness.startTurn("correction", "native-C");
+
+    expect(Date.now() - startedAt).toBeLessThan(5_000);
+    expect(harness.requests("turn/start")).toHaveLength(3);
+    expect(harness.terminated()).toEqual(["201", "202"]);
+  }, 15_000);
+});

plugins/copilot-usage-source/server/usage.test.ts

@@ -171,90 +171,3 @@ it.each([401, 403])("reports an existing login rejected with HTTP %i", async (st
     else process.env["COPILOT_TOKEN"] = previous;
   }
 });
-
-it.each([
-  { remaining: 1500, percentRemaining: 100, usedPct: 0 },
-  { remaining: 1125, percentRemaining: 75, usedPct: 25 },
-  { remaining: 0, percentRemaining: 0, usedPct: 100 },
-])(
-  "reports premium quota with $remaining requests remaining",
-  async ({ remaining, percentRemaining, usedPct }) => {
-    const report = await fetchPremiumQuota({
-      entitlement: 1500,
-      remaining,
-      percent_remaining: percentRemaining,
-      unlimited: false,
-    });
-    expect(report).toMatchObject({
-      status: "available",
-      planLabel: "individual",
-      windows: [
-        {
-          id: "premium_interactions",
-          label: "Premium requests",
-          usedPct,
-          remainingPct: percentRemaining,
-          resetsAt: "2026-12-01T00:00:00.000Z",
-        },
-      ],
-      details: expect.arrayContaining([
-        {
-          id: "premium_remaining",
-          label: "Premium requests remaining",
-          value: `${remaining} / 1500`,
-        },
-      ]),
-    });
-  },
-);
-
-it.each([
-  undefined,
-  null,
-  { unlimited: true, percent_remaining: 100, remaining: 1500, entitlement: 1500 },
-])(
-  "does not invent a finite quota for absent or unlimited premium snapshots (%j)",
-  async (premium) => {
-    const report = await fetchPremiumQuota(premium);
-    expect(report).toMatchObject({
-      status: "available",
-      windows: [],
-      details: [{ id: "reset", label: "Quota reset", value: "2026-12-01" }],
-    });
-  },
-);
-
-it("reports a percentage without inventing missing counts and falls back to the legacy reset", async () => {
-  const report = await fetchPremiumQuota({ percent_remaining: 60, unlimited: false }, null);
-  expect(report).toMatchObject({
-    status: "available",
-    windows: [{ usedPct: 40, remainingPct: 60, resetsAt: "2026-12-01" }],
-    details: [{ id: "reset", label: "Quota reset", value: "2026-12-01" }],
-  });
-});
-
-async function fetchPremiumQuota(
-  premium: unknown,
-  utcReset: string | null = "2026-12-01T00:00:00.000Z",
-) {
-  const { writeFile } = await import("node:fs/promises");
-  const directory = mkdtempSync(join(tmpdir(), "copilot-premium-"));
-  const locator = join(directory, "hosts.yml");
-  try {
-    await writeFile(locator, "github.com:\n  oauth_token: fixture-copilot\n");
-    return await fetchUsage({ store: "file", locator }, async () =>
-      jsonResponse({
-        copilot_plan: "individual",
-        quota_reset_date: "2026-12-01",
-        quota_reset_date_utc: utcReset,
-        quota_snapshots: {
-          premium_interactions: premium,
-          chat: { unlimited: true, percent_remaining: 100 },
-          completions: { unlimited: true, percent_remaining: 100 },
-        },
-      }),
-    );
-  } finally {
-    rmSync(directory, { recursive: true, force: true });
-  }
-}

plugins/copilot-usage-source/server/usage.ts

@@ -5,8 +5,6 @@ import { join } from "node:path";
 import { z } from "zod";
 import {
   unavailable,
-  windowFromUsedPct,
-  type UsageWindow,
   type UsageAccount,
   type UsageReport,
   type UsageDetail,
@@ -20,19 +18,6 @@ const ApiOptionalStringSchema = z.preprocess(
 const CopilotUsageResponseSchema = z.object({
   copilot_plan: ApiOptionalStringSchema,
   quota_reset_date: ApiOptionalStringSchema,
-  quota_reset_date_utc: ApiOptionalStringSchema,
-  quota_snapshots: z
-    .object({
-      premium_interactions: z
-        .object({
-          entitlement: z.number().nonnegative().nullish(),
-          remaining: z.number().nonnegative().nullish(),
-          percent_remaining: z.number().min(0).max(100).nullish(),
-          unlimited: z.boolean().optional(),
-        })
-        .nullish(),
-    })
-    .nullish(),
 });
 
 async function readToken(input: UsageInput): Promise<string | undefined> {
@@ -87,32 +72,10 @@ export async function fetchUsage(
     ? [{ id: "reset", label: "Quota reset", value: resp.quota_reset_date }]
     : [];
 
-  const windows: UsageWindow[] = [];
-  const premium = resp.quota_snapshots?.premium_interactions;
-  if (premium && !premium.unlimited) {
-    if (premium.percent_remaining != null) {
-      windows.push(
-        windowFromUsedPct({
-          id: "premium_interactions",
-          label: "Premium requests",
-          utilizationPct: 100 - premium.percent_remaining,
-          resetsAt: resp.quota_reset_date_utc || resp.quota_reset_date,
-        }),
-      );
-    }
-    if (premium.remaining != null && premium.entitlement != null) {
-      details.push({
-        id: "premium_remaining",
-        label: "Premium requests remaining",
-        value: `${premium.remaining} / ${premium.entitlement}`,
-      });
-    }
-  }
-
   return {
     status: "available",
     planLabel: resp.copilot_plan || undefined,
-    windows,
+    windows: [],
     balances: [],
     details,
   };