diff --git a/src/resources/extensions/gsd/auto-start.ts b/src/resources/extensions/gsd/auto-start.ts
index 5d10a54f8..5856bd0b9 100644
--- a/src/resources/extensions/gsd/auto-start.ts
+++ b/src/resources/extensions/gsd/auto-start.ts
@@ -678,7 +678,7 @@ export async function bootstrapAutoSession(
     }
 
     // ── DB lifecycle ──
-    const gsdDbPath = join(s.basePath, ".gsd", "gsd.db");
+    const gsdDbPath = resolveProjectRootDbPath(s.basePath);
     const gsdDirPath = join(s.basePath, ".gsd");
     if (existsSync(gsdDirPath) && !existsSync(gsdDbPath)) {
       const hasDecisions = existsSync(join(gsdDirPath, "DECISIONS.md"));
diff --git a/src/resources/extensions/gsd/tests/auto-start-worktree-db-path.test.ts b/src/resources/extensions/gsd/tests/auto-start-worktree-db-path.test.ts
new file mode 100644
index 000000000..f32bf41fb
--- /dev/null
+++ b/src/resources/extensions/gsd/tests/auto-start-worktree-db-path.test.ts
@@ -0,0 +1,28 @@
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+
+import { createTestContext } from "./test-helpers.ts";
+
+const { assertTrue, report } = createTestContext();
+
+const srcPath = join(import.meta.dirname, "..", "auto-start.ts");
+const src = readFileSync(srcPath, "utf-8");
+
+console.log("\n=== #3822: worktree bootstrap uses project DB path ===");
+
+const dbLifecycleIdx = src.indexOf("// ── DB lifecycle ──");
+assertTrue(dbLifecycleIdx > 0, "auto-start.ts has a DB lifecycle section");
+
+const dbLifecycleRegion = dbLifecycleIdx > 0 ? src.slice(dbLifecycleIdx, dbLifecycleIdx + 600) : "";
+
+assertTrue(
+  dbLifecycleRegion.includes("const gsdDbPath = resolveProjectRootDbPath(s.basePath);"),
+  "DB lifecycle resolves the project-root DB path after worktree entry (#3822)",
+);
+
+assertTrue(
+  !dbLifecycleRegion.includes('join(s.basePath, ".gsd", "gsd.db")'),
+  "DB lifecycle no longer derives gsd.db directly from the worktree path (#3822)",
+);
+
+report();