diff --git a/src/resources/extensions/gsd/tests/skip-slice-state-rebuild.test.ts b/src/resources/extensions/gsd/tests/skip-slice-state-rebuild.test.ts
new file mode 100644
index 000000000..5a46cdf3c
--- /dev/null
+++ b/src/resources/extensions/gsd/tests/skip-slice-state-rebuild.test.ts
@@ -0,0 +1,31 @@
+/**
+ * Regression test for #3477: gsd_skip_slice tool must rebuild STATE.md
+ * after updating the DB so auto-mode reads the correct state.
+ */
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+
+test("gsd_skip_slice tool calls rebuildState after DB update (#3477)", () => {
+  const src = readFileSync(
+    join(import.meta.dirname, "..", "bootstrap", "db-tools.ts"),
+    "utf-8",
+  );
+  // The fix adds a rebuildState call after updateSliceStatus in skip_slice
+  assert.ok(
+    src.includes("rebuildState"),
+    "gsd_skip_slice must call rebuildState after updating slice status",
+  );
+});
+
+test("rethink prompt warns against markdown-only edits for skip (#3477)", () => {
+  const prompt = readFileSync(
+    join(import.meta.dirname, "..", "prompts", "rethink.md"),
+    "utf-8",
+  );
+  assert.ok(
+    prompt.includes("MUST") && prompt.includes("gsd_skip_slice"),
+    "Rethink prompt must emphasize gsd_skip_slice tool requirement",
+  );
+});