diff --git a/tests/scripts.bats b/tests/scripts.bats
index 5b7fe1b..86d18cd 100644
--- a/tests/scripts.bats
+++ b/tests/scripts.bats
@@ -51,3 +51,18 @@ load helpers
   python3 "$SKILL_SCRIPTS/index-append.py" --section Sources --entry '- [[sources/dup]] — d. `maturity: draft`'
   [ "$(grep -c 'sources/dup' wiki/index.md)" -eq 1 ]
 }
+
+@test "index-append: updates an existing entry by wikilink path (no duplicate)" {
+  G="$(make_fixture_genome)"; cd "$G"
+  python3 "$SKILL_SCRIPTS/index-append.py" --section Sources --entry '- [[sources/foo]] — old summary. `maturity: draft`'
+  python3 "$SKILL_SCRIPTS/index-append.py" --section Sources --entry '- [[sources/foo]] — new summary. `maturity: stable`'
+  [ "$(grep -c 'sources/foo' wiki/index.md)" -eq 1 ]
+  grep -q 'new summary' wiki/index.md
+  ! grep -q 'old summary' wiki/index.md
+}
+
+@test "slug: refuses an all-symbols input (no empty slug)" {
+  run bash "$SKILL_SCRIPTS/slug.sh" "!!!.md"
+  [ "$status" -ne 0 ]
+  [ -z "$output" ] || [[ "$output" != *"feat/ai-ingest-"* ]]
+}