diff --git a/package.json b/package.json
index dbd4c74..354d627 100644
--- a/package.json
+++ b/package.json
@@ -18,6 +18,16 @@
     "onStartupFinished"
   ],
   "contributes": {
+    "configuration": {
+      "title": "Cowriting",
+      "properties": {
+        "cowriting.liveProgress.revealOutput": {
+          "type": "boolean",
+          "default": true,
+          "description": "When Claude is editing, reveal the \"Cowriting: Claude\" output channel (without stealing focus) as soon as Claude starts producing text, so you can read the output as it streams."
+        }
+      }
+    },
     "commands": [
       {
         "command": "cowriting.showClineSdkInfo",
diff --git a/scripts/smoke-live-turn.mjs b/scripts/smoke-live-turn.mjs
index 1a5f17d..9a64d02 100644
--- a/scripts/smoke-live-turn.mjs
+++ b/scripts/smoke-live-turn.mjs
@@ -10,7 +10,15 @@ console.log(`instruction: ${instruction}`);
 console.log(`text:        ${text}`);
 try {
   const t0 = Date.now();
-  const result = await runEditTurn(instruction, text);
+  // #60: exercise the live-progress path against the real SDK — log each reduced
+  // snapshot so the smoke shows streaming/activity/tokens, not just the result.
+  const result = await runEditTurn(instruction, text, {
+    onProgress: (s) => {
+      const bits = [s.phase === "tool" ? `tool:${s.tool}` : s.phase, `${s.chars}c`];
+      if (s.tokens) bits.push(`${s.tokens}tok`);
+      console.log(`  progress: ${bits.join(" ")}`);
+    },
+  });
   console.log(`replacement: ${JSON.stringify(result.replacement)}`);
   console.log(`model:       ${result.model}`);
   console.log(`sessionId:   ${result.sessionId}`);
diff --git a/src/extension.ts b/src/extension.ts
index 1db0f5f..12b1006 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -11,6 +11,7 @@ import { GlobalSidecarStore } from "./globalSidecarStore";
 import { SidecarRouter } from "./sidecarRouter";
 import { DiffViewController } from "./diffViewController";
 import { TrackChangesPreviewController } from "./trackChangesPreview";
+import { LiveProgressUi } from "./liveProgressUi";
 import { isAuthorable, selectionRejection } from "./workspacePath";
 
 const CHANNEL_NAME = "Cowriting (Cline SDK)";
@@ -23,12 +24,18 @@ export interface CowritingApi {
   diffViewController: DiffViewController;
   trackChangesPreviewController: TrackChangesPreviewController;
   sidecarRouter: SidecarRouter;
+  liveProgressUi: LiveProgressUi;
 }
 
 export function activate(context: vscode.ExtensionContext): CowritingApi | undefined {
   // --- POC command (Feature #2), unchanged ---
   const output = vscode.window.createOutputChannel(CHANNEL_NAME);
   context.subscriptions.push(output);
+
+  // #60: shared live-progress UI (notification activity line + "Cowriting: Claude"
+  // OutputChannel) for both Ask-Claude entry points.
+  const liveProgressUi = new LiveProgressUi();
+  context.subscriptions.push(liveProgressUi);
   context.subscriptions.push(
     vscode.commands.registerCommand("cowriting.showClineSdkInfo", async () => {
       try {
@@ -104,6 +111,7 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
     context.extensionUri,
     attributionController,
     proposalController,
+    liveProgressUi,
   );
   context.subscriptions.push(trackChangesPreviewController);
 
@@ -230,10 +238,28 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
       const turnId = `turn-${Date.now().toString(36)}`;
       try {
         await vscode.window.withProgress(
-          { location: vscode.ProgressLocation.Notification, title: "Cowriting: asking Claude…" },
-          async () => {
+          {
+            location: vscode.ProgressLocation.Notification,
+            title: "Cowriting: asking Claude…",
+            cancellable: true,
+          },
+          async (progress, token) => {
             const { runEditTurn } = await import("./liveTurn");
-            const turn = await runEditTurn(instruction, selectedText);
+            const ui = liveProgressUi.begin(instruction, progress, token);
+            let turn;
+            try {
+              turn = await runEditTurn(instruction, selectedText, {
+                onProgress: ui.onProgress,
+                signal: ui.signal,
+              });
+            } catch (err) {
+              // #60 (INV-47): a user cancel surfaces as "cancelled", not a failure.
+              if (token.isCancellationRequested) {
+                void vscode.window.showInformationMessage("Cowriting: Claude edit cancelled.");
+                return;
+              }
+              throw err;
+            }
             if (turn.replacement === "") {
               void vscode.window.showWarningMessage(
                 "Cowriting: Claude returned an empty replacement — nothing was proposed.",
@@ -292,6 +318,7 @@ export function activate(context: vscode.ExtensionContext): CowritingApi | undef
     diffViewController,
     trackChangesPreviewController,
     sidecarRouter,
+    liveProgressUi,
   };
 }
 
diff --git a/src/liveProgressUi.ts b/src/liveProgressUi.ts
new file mode 100644
index 0000000..d693c41
--- /dev/null
+++ b/src/liveProgressUi.ts
@@ -0,0 +1,65 @@
+/**
+ * liveProgressUi.ts — host-side relay of TurnProgress snapshots to VS Code UI
+ * (#60, spec coauthoring-live-progress.md §3.4). The ONLY surfaces are the
+ * existing withProgress notification (an activity line) and a dedicated
+ * OutputChannel streaming the full assistant text — no new network/webview
+ * surface (INV-45). vscode-only; all pure logic lives in turnProgress.ts.
+ */
+import * as vscode from "vscode";
+import { formatProgressLine, type TurnProgressSnapshot } from "./turnProgress";
+
+const CHANNEL_NAME = "Cowriting: Claude";
+
+export interface TurnUi {
+  /** Pass to runEditTurn's opts.onProgress. */
+  onProgress: (snapshot: TurnProgressSnapshot) => void;
+  /** Pass to runEditTurn's opts.signal — fired when the user cancels the notification. */
+  signal: AbortSignal;
+}
+
+export class LiveProgressUi {
+  readonly channel: vscode.OutputChannel;
+
+  constructor() {
+    this.channel = vscode.window.createOutputChannel(CHANNEL_NAME);
+  }
+
+  /**
+   * Begin one turn's UI. Writes the per-turn header to the channel and returns
+   * the onProgress relay + an AbortSignal linked to the notification's cancel
+   * token. The channel APPENDS (it doubles as a debug log of recent turns, spec
+   * §3.5); it auto-reveals (without stealing focus) on the first streamed text,
+   * gated by `cowriting.liveProgress.revealOutput`.
+   */
+  begin(
+    instruction: string,
+    progress: vscode.Progress<{ message?: string }>,
+    token: vscode.CancellationToken,
+  ): TurnUi {
+    const controller = new AbortController();
+    token.onCancellationRequested(() => controller.abort());
+    this.channel.appendLine(`── asking: ${instruction} ──`);
+
+    let revealed = false;
+    const reveal = (): void => {
+      if (revealed) return;
+      revealed = true;
+      const cfg = vscode.workspace.getConfiguration("cowriting");
+      if (cfg.get<boolean>("liveProgress.revealOutput", true)) this.channel.show(true);
+    };
+
+    const onProgress = (s: TurnProgressSnapshot): void => {
+      progress.report({ message: formatProgressLine(s) });
+      if (s.textDelta) {
+        this.channel.append(s.textDelta);
+        reveal();
+      }
+    };
+
+    return { onProgress, signal: controller.signal };
+  }
+
+  dispose(): void {
+    this.channel.dispose();
+  }
+}
diff --git a/src/liveTurn.ts b/src/liveTurn.ts
index 9a4d7ed..3edac9e 100644
--- a/src/liveTurn.ts
+++ b/src/liveTurn.ts
@@ -9,6 +9,9 @@
  * never bundled (esbuild keeps it external).
  */
 
+import type { TurnProgressSnapshot } from "./turnProgress";
+import { createTurnProgressState, reduceTurnProgress } from "./turnProgress";
+
 export interface EditTurnResult {
   replacement: string;
   model: string;
@@ -16,6 +19,19 @@ export interface EditTurnResult {
   sessionId: string;
 }
 
+/**
+ * Options for runEditTurn. Both new fields are purely additive observability /
+ * control over the existing turn (INV-44): `onProgress` streams reduced progress
+ * snapshots out; `signal` cancels the turn in. Neither touches the result path,
+ * and neither pulls `vscode` into this module (INV-43 — `AbortSignal` is a web
+ * standard, the progress snapshot is a domain type).
+ */
+export interface RunEditTurnOptions {
+  modelId?: string;
+  onProgress?: (snapshot: TurnProgressSnapshot) => void;
+  signal?: AbortSignal;
+}
+
 const SYSTEM_PROMPT = [
   "You are a precise text editor embedded in VS Code.",
   "You will be given a piece of text and an instruction.",
@@ -40,7 +56,7 @@ export function extractReplacement(outputText: string, selectedText: string): st
 export async function runEditTurn(
   instruction: string,
   selectedText: string,
-  opts?: { modelId?: string },
+  opts?: RunEditTurnOptions,
 ): Promise<EditTurnResult> {
   const sdk = await import("@cline/sdk");
   const modelId = opts?.modelId ?? "sonnet";
@@ -49,16 +65,50 @@ export async function runEditTurn(
     modelId,
     systemPrompt: SYSTEM_PROMPT,
   });
-  const result = await agent.run(
-    `<instruction>\n${instruction}\n</instruction>\n<text>\n${selectedText}\n</text>`,
-  );
-  // The SDK's AgentRunResult.status union is "completed" | "aborted" | "failed"
-  // (@cline/shared agent.d.ts) — "completed" is the success status.
-  if (result.status !== "completed") {
-    throw new Error(
-      `claude-code turn ${result.status}: ${result.error?.message ?? "unknown error"} ` +
-        "(is Claude Code installed and signed in?)",
+
+  // Stream reduced progress snapshots out (INV-44 additive) and wire cancellation
+  // in via the AbortSignal (INV-47). agent.subscribe returns its unsubscribe fn.
+  let state = createTurnProgressState();
+  const unsubscribe = opts?.onProgress
+    ? agent.subscribe((event) => {
+        const next = reduceTurnProgress(state, event);
+        state = next.state;
+        // Observability must never affect the result (INV-44): a throwing relay
+        // is swallowed, not allowed to propagate into the SDK and fail the turn.
+        if (next.snapshot) {
+          try {
+            opts.onProgress!(next.snapshot);
+          } catch {
+            /* progress is best-effort */
+          }
+        }
+      })
+    : undefined;
+  const onAbort = () => agent.abort();
+  opts?.signal?.addEventListener("abort", onAbort);
+
+  try {
+    // A signal already aborted before the turn starts can't be honored by
+    // agent.abort() (the SDK's AbortController isn't created until run()), so
+    // short-circuit to the same aborted outcome the call site reflects (INV-47).
+    if (opts?.signal?.aborted) {
+      throw new Error("claude-code turn aborted: cancelled before start");
+    }
+    const result = await agent.run(
+      `<instruction>\n${instruction}\n</instruction>\n<text>\n${selectedText}\n</text>`,
     );
+    // The SDK's AgentRunResult.status union is "completed" | "aborted" | "failed"
+    // (@cline/shared agent.d.ts) — "completed" is the success status. An aborted
+    // turn (user cancel) falls into this throw; the call site reflects "cancelled".
+    if (result.status !== "completed") {
+      throw new Error(
+        `claude-code turn ${result.status}: ${result.error?.message ?? "unknown error"} ` +
+          "(is Claude Code installed and signed in?)",
+      );
+    }
+    return { replacement: extractReplacement(result.outputText, selectedText), model: modelId, sessionId: result.runId };
+  } finally {
+    unsubscribe?.();
+    opts?.signal?.removeEventListener("abort", onAbort);
   }
-  return { replacement: extractReplacement(result.outputText, selectedText), model: modelId, sessionId: result.runId };
 }
diff --git a/src/trackChangesPreview.ts b/src/trackChangesPreview.ts
index f7c7f38..037cf91 100644
--- a/src/trackChangesPreview.ts
+++ b/src/trackChangesPreview.ts
@@ -16,10 +16,15 @@ import type { ProposalController } from "./proposalController";
 import { renderReview, renderPlain, diffBlocks, diffToBlockHunks, type BlockOp } from "./trackChangesModel";
 import { buildFingerprint } from "./anchorer";
 import { isAuthorable } from "./workspacePath";
-import type { EditTurnResult } from "./liveTurn";
+import type { EditTurnResult, RunEditTurnOptions } from "./liveTurn";
+import type { LiveProgressUi } from "./liveProgressUi";
 
-/** F11: a host edit turn (selection/document text + instruction → rewrite). Injectable for tests. */
-type EditTurn = (instruction: string, text: string) => Promise<EditTurnResult>;
+/**
+ * F11: a host edit turn (selection/document text + instruction → rewrite).
+ * Injectable for tests. #60: accepts optional turn options (onProgress/signal);
+ * the arg is optional so existing test stubs that ignore it stay valid.
+ */
+type EditTurn = (instruction: string, text: string, opts?: RunEditTurnOptions) => Promise<EditTurnResult>;
 /** F11: what an Ask-Claude gesture edits — a resolved selection range, or the whole document. */
 type EditTarget = { kind: "range"; start: number; end: number } | { kind: "document" };
 
@@ -53,9 +58,9 @@ export class TrackChangesPreviewController implements vscode.Disposable {
    * F11: the host edit turn (INV-8 — runs host-side, @cline/sdk loaded lazily and
    * never bundled). Injectable so host E2E can stub it (no LLM in CI).
    */
-  private editTurn: EditTurn = async (instruction, text) => {
+  private editTurn: EditTurn = async (instruction, text, opts) => {
     const { runEditTurn } = await import("./liveTurn");
-    return runEditTurn(instruction, text);
+    return runEditTurn(instruction, text, opts);
   };
   /** Monotonic per-session counter minting a stable turnId for each Ask-Claude gesture. */
   private turnSeq = 0;
@@ -68,6 +73,7 @@ export class TrackChangesPreviewController implements vscode.Disposable {
     private readonly extensionUri: vscode.Uri,
     private readonly attribution: AttributionController,
     private readonly proposals: ProposalController,
+    private readonly liveProgressUi: LiveProgressUi,
   ) {
     this.disposables.push(
       // F11 (SLICE-5): the editor/title gateway passes the tab's resource Uri;
@@ -230,8 +236,24 @@ export class TrackChangesPreviewController implements vscode.Disposable {
     if (!instruction) return;
     try {
       const ids = await vscode.window.withProgress(
-        { location: vscode.ProgressLocation.Notification, title: "Cowriting: asking Claude…" },
-        () => this.runEditAndPropose(document, target, instruction),
+        {
+          location: vscode.ProgressLocation.Notification,
+          title: "Cowriting: asking Claude…",
+          cancellable: true,
+        },
+        async (progress, token) => {
+          const ui = this.liveProgressUi.begin(instruction, progress, token);
+          try {
+            return await this.runEditAndPropose(document, target, instruction, {
+              onProgress: ui.onProgress,
+              signal: ui.signal,
+            });
+          } catch (err) {
+            // #60 (INV-47): a user cancel proposes nothing (the benign empty path).
+            if (token.isCancellationRequested) return [] as string[];
+            throw err;
+          }
+        },
       );
       if (ids.length === 0) {
         void vscode.window.showInformationMessage("Cowriting: Claude proposed no changes.");
@@ -258,6 +280,7 @@ export class TrackChangesPreviewController implements vscode.Disposable {
     document: vscode.TextDocument,
     target: EditTarget,
     instruction: string,
+    opts?: RunEditTurnOptions,
   ): Promise<string[]> {
     const full = document.getText();
     // One turnId per gesture — the document case's N hunk-proposals all share it,
@@ -267,13 +290,13 @@ export class TrackChangesPreviewController implements vscode.Disposable {
       ({ kind: "agent" as const, id: "claude", agent: { sdk: "@cline/sdk", model: turn.model, sessionId: turn.sessionId } });
     if (target.kind === "range") {
       const selected = full.slice(target.start, target.end);
-      const turn = await this.editTurn(instruction, selected);
+      const turn = await this.editTurn(instruction, selected, opts);
       if (turn.replacement === "" || turn.replacement === selected) return [];
       const fp = buildFingerprint(full, { start: target.start, end: target.end });
       const id = await this.proposals.propose(document, fp, turn.replacement, provenance(turn), { turnId, instruction });
       return id ? [id] : [];
     }
-    const turn = await this.editTurn(instruction, full);
+    const turn = await this.editTurn(instruction, full, opts);
     const ids: string[] = [];
     // #47 (INV-39, supersedes INV-37): a document rewrite is cut at BLOCK
     // granularity — one proposal per changed block (the unit a human reviews) —
diff --git a/src/turnProgress.ts b/src/turnProgress.ts
new file mode 100644
index 0000000..b00cc81
--- /dev/null
+++ b/src/turnProgress.ts
@@ -0,0 +1,122 @@
+/**
+ * turnProgress.ts — pure reduction of @cline/sdk Agent runtime events into a
+ * small UI-facing progress snapshot (#60, spec coauthoring-live-progress.md §3.2).
+ *
+ * INV-43: vscode-free. INV-46: a pure function — no vscode, no SDK runtime
+ * dependency (`AgentRuntimeEvent` is imported TYPE-only, so it is erased at
+ * compile and never pulls the ESM SDK into the bundle). All event→state logic
+ * lives here so it is unit-tested in isolation; the UI call sites only format and
+ * relay snapshots.
+ */
+import type { AgentRuntimeEvent } from "@cline/shared";
+
+export type TurnPhase = "thinking" | "writing" | "tool";
+
+export interface TurnProgressSnapshot {
+  phase: TurnPhase;
+  /** present iff phase === "tool" — the running tool's name. */
+  tool?: string;
+  /** accumulated assistant-text length so far. */
+  chars: number;
+  /** running total tokens (input+output); undefined until the first usage event. */
+  tokens?: number;
+  /** the new assistant-text chunk since the last snapshot (for the OutputChannel). */
+  textDelta?: string;
+}
+
+export interface TurnProgressState {
+  phase: TurnPhase;
+  chars: number;
+  tokens?: number;
+  /** stack of tool names currently running (depth-tracked for overlap). */
+  activeTools: string[];
+  /** true once any assistant text has streamed (tool-finish then reverts to writing). */
+  sawText: boolean;
+}
+
+export function createTurnProgressState(): TurnProgressState {
+  return { phase: "thinking", chars: 0, tokens: undefined, activeTools: [], sawText: false };
+}
+
+function restingPhase(state: TurnProgressState): TurnPhase {
+  if (state.activeTools.length) return "tool";
+  return state.sawText ? "writing" : "thinking";
+}
+
+function toSnapshot(state: TurnProgressState, textDelta?: string): TurnProgressSnapshot {
+  return {
+    phase: state.phase,
+    tool: state.phase === "tool" ? state.activeTools[state.activeTools.length - 1] : undefined,
+    chars: state.chars,
+    tokens: state.tokens,
+    textDelta,
+  };
+}
+
+/**
+ * Fold one SDK event into the state, returning the next state and the snapshot to
+ * emit (snapshot undefined for events that don't change the surface).
+ */
+export function reduceTurnProgress(
+  state: TurnProgressState,
+  event: AgentRuntimeEvent,
+): { state: TurnProgressState; snapshot?: TurnProgressSnapshot } {
+  switch (event.type) {
+    case "run-started":
+    case "turn-started": {
+      const next: TurnProgressState = { ...state, phase: restingPhase(state) };
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    case "assistant-text-delta": {
+      const next: TurnProgressState = {
+        ...state,
+        phase: state.activeTools.length ? "tool" : "writing",
+        chars: event.accumulatedText.length,
+        sawText: true,
+      };
+      return { state: next, snapshot: toSnapshot(next, event.text) };
+    }
+    case "assistant-reasoning-delta": {
+      // Reasoning TEXT is not surfaced (operator fork); collapse to motion only.
+      const next: TurnProgressState = { ...state, phase: state.activeTools.length ? "tool" : "thinking" };
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    case "tool-started": {
+      const activeTools = [...state.activeTools, event.toolCall.toolName];
+      const next: TurnProgressState = { ...state, phase: "tool", activeTools };
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    case "tool-updated": {
+      const next: TurnProgressState = { ...state, phase: "tool" };
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    case "tool-finished": {
+      const name = event.toolCall.toolName;
+      const idx = state.activeTools.lastIndexOf(name);
+      const activeTools = idx >= 0 ? state.activeTools.filter((_, i) => i !== idx) : state.activeTools.slice(0, -1);
+      const next: TurnProgressState = { ...state, activeTools, phase: "thinking" };
+      next.phase = restingPhase(next);
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    case "usage-updated": {
+      const tokens = event.usage.inputTokens + event.usage.outputTokens || undefined;
+      const next: TurnProgressState = { ...state, tokens };
+      return { state: next, snapshot: toSnapshot(next) };
+    }
+    default:
+      return { state };
+  }
+}
+
+/** Render the notification activity line from a snapshot (pure; spec §2.1). */
+export function formatProgressLine(s: TurnProgressSnapshot): string {
+  let head: string;
+  if (s.phase === "tool") head = `running ${s.tool ?? "tool"}…`;
+  else if (s.phase === "writing") head = `writing… (${s.chars} chars)`;
+  else head = "thinking…";
+  return s.tokens ? `${head} · ${formatTokens(s.tokens)} tokens` : head;
+}
+
+export function formatTokens(n: number): string {
+  return n >= 1000 ? `${(n / 1000).toFixed(1)}k` : String(n);
+}
diff --git a/test/e2e/suite/liveProgress.test.ts b/test/e2e/suite/liveProgress.test.ts
new file mode 100644
index 0000000..a10bbe7
--- /dev/null
+++ b/test/e2e/suite/liveProgress.test.ts
@@ -0,0 +1,83 @@
+import * as assert from "assert";
+import * as fs from "fs";
+import * as path from "path";
+import * as vscode from "vscode";
+import type { CowritingApi } from "../../../src/extension";
+
+const WS = process.env.E2E_WORKSPACE!;
+const settle = () => new Promise((r) => setTimeout(r, 400));
+
+async function getApi(): Promise<CowritingApi> {
+  const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
+  const api = (await ext.activate()) as CowritingApi;
+  assert.ok(api?.trackChangesPreviewController, "exports preview controller");
+  return api;
+}
+
+async function freshDoc(rel: string, body: string): Promise<vscode.TextDocument> {
+  const abs = path.join(WS, rel);
+  fs.mkdirSync(path.dirname(abs), { recursive: true });
+  fs.writeFileSync(abs, body, "utf8");
+  const doc = await vscode.workspace.openTextDocument(vscode.Uri.file(abs));
+  await vscode.window.showTextDocument(doc);
+  await settle();
+  return doc;
+}
+
+// #60 host E2E (no LLM): live progress is purely additive observability. The
+// harness can't read notification subtitles, so it asserts the CONTRACT —
+// progress events don't change the proposals (INV-44), and an aborted turn
+// proposes nothing (INV-47). The live notification/OutputChannel UI itself is
+// covered by the turnProgress unit tests + the manual smoke.
+suite("#60 live turn progress (additive + cancel)", () => {
+  test("a stub that emits progress still produces the same proposals (INV-44)", async () => {
+    const doc = await freshDoc("docs/live60-additive.md", "# Title\n\nOld paragraph.\n");
+    const api = await getApi();
+    const ctl = api.trackChangesPreviewController;
+    await vscode.commands.executeCommand("cowriting.showTrackChangesPreview");
+    await settle();
+
+    // The stub honors opts.onProgress (emitting synthetic snapshots) but returns
+    // the same rewrite — proposals must be unaffected by progress events.
+    ctl.setEditTurnForTest(async (_i, _text, opts) => {
+      opts?.onProgress?.({ phase: "writing", chars: 5 });
+      opts?.onProgress?.({ phase: "writing", chars: 13, tokens: 1234, textDelta: "New paragraph." });
+      return { replacement: "# Title\n\nNew paragraph.\n", model: "sonnet", sessionId: "e2e-live60" };
+    });
+
+    const ids = await ctl.runEditAndPropose(doc, { kind: "document" }, "rewrite the paragraph");
+    await settle();
+    assert.strictEqual(ids.length, 1, "one changed block → one proposal, regardless of progress events");
+    const view = api.proposalController.listProposals(doc).find((v) => v.id === ids[0]);
+    assert.ok(view, "the proposal is live");
+    assert.ok(doc.getText().includes("Old paragraph."), "document unchanged by propose (INV-10)");
+  });
+
+  test("an aborted turn proposes nothing (INV-47)", async () => {
+    const doc = await freshDoc("docs/live60-cancel.md", "# Title\n\nOld paragraph.\n");
+    const api = await getApi();
+    const ctl = api.trackChangesPreviewController;
+    await vscode.commands.executeCommand("cowriting.showTrackChangesPreview");
+    await settle();
+
+    // The stub throws ONLY when the aborted signal reached it — so if opts.signal
+    // failed to thread through runEditAndPropose, the stub would instead return a
+    // rewrite and create a proposal, failing this test. That proves propagation.
+    ctl.setEditTurnForTest(async (_i, _text, opts) => {
+      if (opts?.signal?.aborted) throw new Error("claude-code turn aborted");
+      return { replacement: "# Title\n\nSHOULD NOT BE PROPOSED.\n", model: "sonnet", sessionId: "e2e-live60-nope" };
+    });
+
+    const ac = new AbortController();
+    ac.abort();
+    let ids: string[] = [];
+    try {
+      ids = await ctl.runEditAndPropose(doc, { kind: "document" }, "rewrite", { signal: ac.signal });
+    } catch {
+      ids = [];
+    }
+    await settle();
+    assert.strictEqual(ids.length, 0, "aborted turn must create no proposals");
+    assert.strictEqual(api.proposalController.listProposals(doc).length, 0, "no pending proposals after abort");
+  });
+});
diff --git a/test/liveTurn.test.ts b/test/liveTurn.test.ts
index da8596e..32f022d 100644
--- a/test/liveTurn.test.ts
+++ b/test/liveTurn.test.ts
@@ -1,5 +1,32 @@
-import { describe, it, expect } from "vitest";
-import { extractReplacement } from "../src/liveTurn";
+import { describe, it, expect, vi } from "vitest";
+import { extractReplacement, runEditTurn } from "../src/liveTurn";
+
+// A fake Agent that replays a scripted event list to subscribers, supports abort,
+// and resolves agent.run() with a completed (or aborted) result.
+const runs = { count: 0 };
+function fakeSdk(events: any[]) {
+  return {
+    Agent: class {
+      private listeners: ((e: any) => void)[] = [];
+      constructor(_cfg: unknown) {}
+      subscribe(fn: (e: any) => void) {
+        this.listeners.push(fn);
+        return () => {
+          this.listeners = this.listeners.filter((l) => l !== fn);
+        };
+      }
+      // The real SDK's abort() is a no-op before run() creates its AbortController,
+      // so this fake does NOT cooperate with a pre-abort — proving runEditTurn's own
+      // short-circuit, not the fake's leniency.
+      abort() {}
+      async run(_input: string) {
+        runs.count += 1;
+        for (const e of events) for (const l of this.listeners) l(e);
+        return { status: "completed", outputText: "EDITED", runId: "r1" };
+      }
+    },
+  };
+}
 
 describe("extractReplacement", () => {
   it("returns plain text untouched", () => {
@@ -24,3 +51,33 @@ describe("extractReplacement", () => {
     expect(extractReplacement("```\nplain\n```", "plain old text")).toBe("plain");
   });
 });
+
+describe("runEditTurn progress + cancel", () => {
+  it("emits progress snapshots and returns the replacement unchanged (INV-44)", async () => {
+    vi.resetModules();
+    vi.doMock("@cline/sdk", () =>
+      fakeSdk([
+        { type: "assistant-text-delta", text: "ED", accumulatedText: "ED" },
+        { type: "usage-updated", usage: { inputTokens: 10, outputTokens: 5, cacheReadTokens: 0, cacheWriteTokens: 0 } },
+      ]),
+    );
+    const seen: string[] = [];
+    const turn = await runEditTurn("do it", "old", { onProgress: (s) => seen.push(s.phase) });
+    expect(turn.replacement).toBe("EDITED");
+    expect(seen).toContain("writing");
+    vi.doUnmock("@cline/sdk");
+    vi.resetModules();
+  });
+
+  it("a pre-aborted AbortSignal short-circuits before run() and throws (INV-47)", async () => {
+    vi.resetModules();
+    vi.doMock("@cline/sdk", () => fakeSdk([]));
+    runs.count = 0;
+    const ac = new AbortController();
+    ac.abort();
+    await expect(runEditTurn("do it", "old", { signal: ac.signal })).rejects.toThrow(/aborted/);
+    expect(runs.count).toBe(0); // the turn never ran — no proposal could be produced
+    vi.doUnmock("@cline/sdk");
+    vi.resetModules();
+  });
+});
diff --git a/test/turnProgress.test.ts b/test/turnProgress.test.ts
new file mode 100644
index 0000000..98b9e82
--- /dev/null
+++ b/test/turnProgress.test.ts
@@ -0,0 +1,102 @@
+import { describe, it, expect } from "vitest";
+import {
+  createTurnProgressState,
+  reduceTurnProgress,
+  formatProgressLine,
+  formatTokens,
+  type TurnProgressSnapshot,
+} from "../src/turnProgress";
+
+// Minimal event factories — structurally match the @cline/sdk AgentRuntimeEvent
+// members the reducer reads. `as any` because we only supply the fields used.
+const ev = (e: any) => e as any;
+const textDelta = (text: string, accumulatedText: string) =>
+  ev({ type: "assistant-text-delta", text, accumulatedText });
+const toolStarted = (toolName: string) => ev({ type: "tool-started", toolCall: { toolName } });
+const toolFinished = (toolName: string) => ev({ type: "tool-finished", toolCall: { toolName } });
+const usage = (inputTokens: number, outputTokens: number) =>
+  ev({ type: "usage-updated", usage: { inputTokens, outputTokens, cacheReadTokens: 0, cacheWriteTokens: 0 } });
+
+// Drive a sequence of events, returning every emitted snapshot.
+function run(events: any[]): TurnProgressSnapshot[] {
+  let state = createTurnProgressState();
+  const out: TurnProgressSnapshot[] = [];
+  for (const e of events) {
+    const r = reduceTurnProgress(state, e);
+    state = r.state;
+    if (r.snapshot) out.push(r.snapshot);
+  }
+  return out;
+}
+
+describe("reduceTurnProgress", () => {
+  it("starts in thinking", () => {
+    const s = run([ev({ type: "run-started" })]);
+    expect(s.at(-1)!.phase).toBe("thinking");
+    expect(s.at(-1)!.chars).toBe(0);
+    expect(s.at(-1)!.tokens).toBeUndefined();
+  });
+
+  it("text deltas move to writing and accumulate chars + carry the delta", () => {
+    const s = run([textDelta("Hel", "Hel"), textDelta("lo", "Hello")]);
+    expect(s.map((x) => x.phase)).toEqual(["writing", "writing"]);
+    expect(s.at(-1)!.chars).toBe(5);
+    expect(s.map((x) => x.textDelta)).toEqual(["Hel", "lo"]);
+  });
+
+  it("usage sets a running token total (input+output)", () => {
+    const s = run([textDelta("Hi", "Hi"), usage(1000, 234)]);
+    expect(s.at(-1)!.tokens).toBe(1234);
+  });
+
+  it("tool start shows the tool name; tool finish reverts to writing once text was seen", () => {
+    const s = run([textDelta("x", "x"), toolStarted("read_file"), toolFinished("read_file")]);
+    expect(s[1].phase).toBe("tool");
+    expect(s[1].tool).toBe("read_file");
+    expect(s.at(-1)!.phase).toBe("writing");
+  });
+
+  it("tool finish reverts to thinking when no text was seen", () => {
+    const s = run([toolStarted("grep"), toolFinished("grep")]);
+    expect(s.at(-1)!.phase).toBe("thinking");
+  });
+
+  it("overlapping tools resolve in order", () => {
+    const s = run([toolStarted("a"), toolStarted("b"), toolFinished("b"), toolFinished("a")]);
+    expect(s.map((x) => x.phase)).toEqual(["tool", "tool", "tool", "thinking"]);
+    expect(s[1].tool).toBe("b");
+    expect(s[2].tool).toBe("a");
+  });
+
+  it("reasoning deltas stay thinking and surface no text", () => {
+    const s = run([ev({ type: "assistant-reasoning-delta", text: "secret", accumulatedText: "secret" })]);
+    expect(s.at(-1)!.phase).toBe("thinking");
+    expect(s.at(-1)!.textDelta).toBeUndefined();
+  });
+
+  it("ignores lifecycle/finish events (no snapshot)", () => {
+    const s = run([ev({ type: "turn-finished" }), ev({ type: "run-finished" })]);
+    expect(s).toEqual([]);
+  });
+});
+
+describe("formatProgressLine / formatTokens", () => {
+  it("thinking", () => {
+    expect(formatProgressLine({ phase: "thinking", chars: 0 })).toBe("thinking…");
+  });
+  it("writing with chars", () => {
+    expect(formatProgressLine({ phase: "writing", chars: 412 })).toBe("writing… (412 chars)");
+  });
+  it("writing with chars + tokens", () => {
+    expect(formatProgressLine({ phase: "writing", chars: 412, tokens: 1234 })).toBe(
+      "writing… (412 chars) · 1.2k tokens",
+    );
+  });
+  it("tool with name", () => {
+    expect(formatProgressLine({ phase: "tool", tool: "read_file", chars: 0 })).toBe("running read_file…");
+  });
+  it("formats token magnitudes", () => {
+    expect(formatTokens(950)).toBe("950");
+    expect(formatTokens(1234)).toBe("1.2k");
+  });
+});