diff --git a/src/resources/extensions/gsd/journal.ts b/src/resources/extensions/gsd/journal.ts
index 9b1fa9487..5b7003781 100644
--- a/src/resources/extensions/gsd/journal.ts
+++ b/src/resources/extensions/gsd/journal.ts
@@ -32,7 +32,12 @@ export type JournalEventType =
   | "milestone-transition"
   | "stuck-detected"
   | "sidecar-dequeue"
-  | "iteration-end";
+  | "iteration-end"
+  | "worktree-enter"
+  | "worktree-create-failed"
+  | "worktree-skip"
+  | "worktree-merge-start"
+  | "worktree-merge-failed";
 
 /** A single structured event in the journal. */
 export interface JournalEntry {
diff --git a/src/resources/extensions/gsd/tests/merge-conflict-stops-loop.test.ts b/src/resources/extensions/gsd/tests/merge-conflict-stops-loop.test.ts
index 5afca834c..1b6450ee7 100644
--- a/src/resources/extensions/gsd/tests/merge-conflict-stops-loop.test.ts
+++ b/src/resources/extensions/gsd/tests/merge-conflict-stops-loop.test.ts
@@ -27,7 +27,7 @@ console.log("\n=== #2330: Merge conflict stops auto loop ===");
 const methodStart = resolverSrc.indexOf("Worktree-mode merge:");
 assertTrue(methodStart > 0, "worktree-resolver has _mergeWorktreeMode method");
 
-const methodBody = resolverSrc.slice(methodStart, methodStart + 5000);
+const methodBody = resolverSrc.slice(methodStart, methodStart + 6000);
 const rethrowsConflict =
   methodBody.includes("MergeConflictError") &&
   methodBody.includes("throw err");
diff --git a/src/resources/extensions/gsd/tests/worktree-journal-events.test.ts b/src/resources/extensions/gsd/tests/worktree-journal-events.test.ts
new file mode 100644
index 000000000..b0bb7631b
--- /dev/null
+++ b/src/resources/extensions/gsd/tests/worktree-journal-events.test.ts
@@ -0,0 +1,220 @@
+import { describe, test, beforeEach, afterEach } from "node:test";
+import assert from "node:assert/strict";
+import { mkdtempSync, rmSync, readFileSync, readdirSync } from "node:fs";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import {
+  WorktreeResolver,
+  type WorktreeResolverDeps,
+  type NotifyCtx,
+} from "../worktree-resolver.js";
+import { AutoSession } from "../auto/session.js";
+import type { JournalEntry } from "../journal.js";
+
+// ─── Helpers ─────────────────────────────────────────────────────────────────
+
+function makeSession(
+  overrides?: Partial<{ basePath: string; originalBasePath: string }>,
+): AutoSession {
+  const s = new AutoSession();
+  s.basePath = overrides?.basePath ?? "/project";
+  s.originalBasePath = overrides?.originalBasePath ?? "/project";
+  return s;
+}
+
+function makeDeps(
+  overrides?: Partial<WorktreeResolverDeps>,
+): WorktreeResolverDeps {
+  const deps: WorktreeResolverDeps = {
+    isInAutoWorktree: () => false,
+    shouldUseWorktreeIsolation: () => true,
+    getIsolationMode: () => "worktree",
+    mergeMilestoneToMain: () => ({ pushed: false, codeFilesChanged: true }),
+    syncWorktreeStateBack: () => ({ synced: [] }),
+    teardownAutoWorktree: () => {},
+    createAutoWorktree: (_basePath: string, milestoneId: string) =>
+      `/project/.gsd/worktrees/${milestoneId}`,
+    enterAutoWorktree: (_basePath: string, milestoneId: string) =>
+      `/project/.gsd/worktrees/${milestoneId}`,
+    getAutoWorktreePath: () => null,
+    autoCommitCurrentBranch: () => {},
+    getCurrentBranch: () => "main",
+    autoWorktreeBranch: (milestoneId: string) => `milestone/${milestoneId}`,
+    resolveMilestoneFile: (_basePath: string, milestoneId: string) =>
+      `/project/.gsd/milestones/${milestoneId}/${milestoneId}-ROADMAP.md`,
+    readFileSync: () => "# Roadmap\n- [x] S01: Slice one\n",
+    GitServiceImpl: class {
+      constructor() {}
+    } as unknown as WorktreeResolverDeps["GitServiceImpl"],
+    loadEffectiveGSDPreferences: () => ({ preferences: { git: {} } }),
+    invalidateAllCaches: () => {},
+    captureIntegrationBranch: () => {},
+    ...overrides,
+  };
+  return deps;
+}
+
+function makeNotifyCtx(): NotifyCtx {
+  return {
+    notify: () => {},
+  };
+}
+
+/** Read all journal entries from a temp .gsd/journal directory. */
+function readJournalEntries(basePath: string): JournalEntry[] {
+  const journalDir = join(basePath, ".gsd", "journal");
+  try {
+    const files = readdirSync(journalDir).filter(f => f.endsWith(".jsonl")).sort();
+    const entries: JournalEntry[] = [];
+    for (const file of files) {
+      const raw = readFileSync(join(journalDir, file), "utf-8");
+      for (const line of raw.split("\n")) {
+        if (!line.trim()) continue;
+        entries.push(JSON.parse(line) as JournalEntry);
+      }
+    }
+    return entries;
+  } catch {
+    return [];
+  }
+}
+
+// ─── Tests ───────────────────────────────────────────────────────────────────
+
+describe("worktree journal events", () => {
+  let tmp: string;
+  const originalCwd = process.cwd();
+
+  beforeEach(() => {
+    tmp = mkdtempSync(join(tmpdir(), "wt-journal-"));
+  });
+  afterEach(() => {
+    // Restore cwd before cleanup — on Windows, rmSync fails with EPERM
+    // if the process cwd is inside the directory being deleted.
+    try { process.chdir(originalCwd); } catch { /* best-effort */ }
+    rmSync(tmp, { recursive: true, force: true });
+  });
+
+  test("enterMilestone emits worktree-enter on success (new worktree)", () => {
+    const s = makeSession({ basePath: tmp, originalBasePath: tmp });
+    const deps = makeDeps({ getAutoWorktreePath: () => null });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.enterMilestone("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const enter = entries.find(e => e.eventType === "worktree-enter");
+    assert.ok(enter, "worktree-enter event should be emitted");
+    assert.equal(enter!.data?.milestoneId, "M001");
+    assert.equal(enter!.data?.created, true);
+    assert.ok(enter!.data?.wtPath);
+  });
+
+  test("enterMilestone emits worktree-enter with created=false for existing worktree", () => {
+    const s = makeSession({ basePath: tmp, originalBasePath: tmp });
+    const deps = makeDeps({
+      getAutoWorktreePath: () => "/project/.gsd/worktrees/M001",
+    });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.enterMilestone("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const enter = entries.find(e => e.eventType === "worktree-enter");
+    assert.ok(enter, "worktree-enter event should be emitted");
+    assert.equal(enter!.data?.created, false);
+  });
+
+  test("enterMilestone emits worktree-skip when isolation disabled", () => {
+    const s = makeSession({ basePath: tmp, originalBasePath: tmp });
+    const deps = makeDeps({ shouldUseWorktreeIsolation: () => false });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.enterMilestone("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const skip = entries.find(e => e.eventType === "worktree-skip");
+    assert.ok(skip, "worktree-skip event should be emitted");
+    assert.equal(skip!.data?.milestoneId, "M001");
+    assert.equal(skip!.data?.reason, "isolation-disabled");
+  });
+
+  test("enterMilestone emits worktree-create-failed on error", () => {
+    const s = makeSession({ basePath: tmp, originalBasePath: tmp });
+    const deps = makeDeps({
+      getAutoWorktreePath: () => null,
+      createAutoWorktree: () => { throw new Error("disk full"); },
+    });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.enterMilestone("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const failed = entries.find(e => e.eventType === "worktree-create-failed");
+    assert.ok(failed, "worktree-create-failed event should be emitted");
+    assert.equal(failed!.data?.milestoneId, "M001");
+    assert.equal(failed!.data?.error, "disk full");
+    assert.equal(failed!.data?.fallback, "project-root");
+  });
+
+  test("mergeAndExit emits worktree-merge-start", () => {
+    const s = makeSession({
+      basePath: join(tmp, "worktree"),
+      originalBasePath: tmp,
+    });
+    const deps = makeDeps({
+      isInAutoWorktree: () => true,
+      getIsolationMode: () => "worktree",
+    });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.mergeAndExit("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const start = entries.find(e => e.eventType === "worktree-merge-start");
+    assert.ok(start, "worktree-merge-start event should be emitted");
+    assert.equal(start!.data?.milestoneId, "M001");
+    assert.equal(start!.data?.mode, "worktree");
+  });
+
+  test("mergeAndExit emits worktree-merge-failed on error", () => {
+    const s = makeSession({
+      basePath: join(tmp, "worktree"),
+      originalBasePath: tmp,
+    });
+    const deps = makeDeps({
+      isInAutoWorktree: () => true,
+      getIsolationMode: () => "worktree",
+      mergeMilestoneToMain: () => { throw new Error("conflict in main"); },
+    });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.mergeAndExit("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    const failed = entries.find(e => e.eventType === "worktree-merge-failed");
+    assert.ok(failed, "worktree-merge-failed event should be emitted");
+    assert.equal(failed!.data?.milestoneId, "M001");
+    assert.equal(failed!.data?.error, "conflict in main");
+  });
+
+  test("journal entries have valid flowId, seq, and ts fields", () => {
+    const s = makeSession({ basePath: tmp, originalBasePath: tmp });
+    const deps = makeDeps({ shouldUseWorktreeIsolation: () => false });
+    const resolver = new WorktreeResolver(s, deps);
+
+    resolver.enterMilestone("M001", makeNotifyCtx());
+
+    const entries = readJournalEntries(tmp);
+    assert.ok(entries.length > 0, "at least one entry should exist");
+    const entry = entries[0];
+    assert.ok(entry.flowId, "flowId should be set");
+    assert.ok(
+      /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/.test(entry.flowId),
+      "flowId should be a valid UUID",
+    );
+    assert.equal(entry.seq, 0);
+    assert.ok(entry.ts, "ts should be set");
+    assert.ok(!isNaN(Date.parse(entry.ts)), "ts should be a valid ISO date");
+  });
+});
diff --git a/src/resources/extensions/gsd/worktree-resolver.ts b/src/resources/extensions/gsd/worktree-resolver.ts
index 093899297..1ebc1e920 100644
--- a/src/resources/extensions/gsd/worktree-resolver.ts
+++ b/src/resources/extensions/gsd/worktree-resolver.ts
@@ -14,10 +14,12 @@
  */
 
 import { existsSync, unlinkSync } from "node:fs";
+import { randomUUID } from "node:crypto";
 import { join } from "node:path";
 import type { AutoSession } from "./auto/session.js";
 import { debugLog } from "./debug-logger.js";
 import { MergeConflictError } from "./git-service.js";
+import { emitJournalEvent } from "./journal.js";
 
 // ─── Dependency Interface ──────────────────────────────────────────────────
 
@@ -155,6 +157,13 @@ export class WorktreeResolver {
         skipped: true,
         reason: "isolation-disabled",
       });
+      emitJournalEvent(this.s.originalBasePath || this.s.basePath, {
+        ts: new Date().toISOString(),
+        flowId: randomUUID(),
+        seq: 0,
+        eventType: "worktree-skip",
+        data: { milestoneId, reason: "isolation-disabled" },
+      });
       return;
     }
 
@@ -184,6 +193,13 @@ export class WorktreeResolver {
         result: "success",
         wtPath,
       });
+      emitJournalEvent(this.s.originalBasePath || this.s.basePath, {
+        ts: new Date().toISOString(),
+        flowId: randomUUID(),
+        seq: 0,
+        eventType: "worktree-enter",
+        data: { milestoneId, wtPath, created: !existingPath },
+      });
       ctx.notify(`Entered worktree for ${milestoneId} at ${wtPath}`, "info");
     } catch (err) {
       const msg = err instanceof Error ? err.message : String(err);
@@ -193,6 +209,13 @@ export class WorktreeResolver {
         result: "error",
         error: msg,
       });
+      emitJournalEvent(this.s.originalBasePath || this.s.basePath, {
+        ts: new Date().toISOString(),
+        flowId: randomUUID(),
+        seq: 0,
+        eventType: "worktree-create-failed",
+        data: { milestoneId, error: msg, fallback: "project-root" },
+      });
       ctx.notify(
         `Auto-worktree creation for ${milestoneId} failed: ${msg}. Continuing in project root.`,
         "warning",
@@ -288,6 +311,13 @@ export class WorktreeResolver {
       mode,
       basePath: this.s.basePath,
     });
+    emitJournalEvent(this.s.originalBasePath || this.s.basePath, {
+      ts: new Date().toISOString(),
+      flowId: randomUUID(),
+      seq: 0,
+      eventType: "worktree-merge-start",
+      data: { milestoneId, mode },
+    });
 
     if (mode === "none") {
       debugLog("WorktreeResolver", {
@@ -408,6 +438,13 @@ export class WorktreeResolver {
         error: msg,
         fallback: "chdir-to-project-root",
       });
+      emitJournalEvent(this.s.originalBasePath || this.s.basePath, {
+        ts: new Date().toISOString(),
+        flowId: randomUUID(),
+        seq: 0,
+        eventType: "worktree-merge-failed",
+        data: { milestoneId, error: msg },
+      });
       // Surface a clear, actionable error. The worktree and milestone branch are
       // intentionally preserved — nothing has been deleted. The user can retry
       // /gsd dispatch complete-milestone or merge manually once the underlying issue is fixed