fix: assign backend label per code path in vouch search CLI

CHANGELOG.md

@@ -6,6 +6,9 @@ All notable changes to vouch are documented here. Format follows
 
 ## [Unreleased]
 
+### Fixed
+- Fix `vouch search` CLI: assign backend label per code path so substring fallback results are no longer mislabelled as `fts5`; update stale docstring to reflect multi-backend search surface (#52).
+
 ### Fixed
 - Bundle import rejects tar members whose path escapes `kb_dir`
   (CVE-2007-4559, #9). Previously a crafted `.tar.gz` with a member

src/vouch/cli.py

@@ -466,7 +466,7 @@ def crystallize(session_id: str, no_page: bool) -> None:
 @click.argument("query")
 @click.option("--limit", default=10, show_default=True, type=int)
 def search(query: str, limit: int) -> None:
-    """FTS5 search over claims, pages, and entities."""
+    """Search claims, pages, and entities (embedding → fts5 → substring)."""
     from . import index_db
     store = _load_store()
     try:

tests/test_cli.py

@@ -78,3 +78,44 @@ def test_propose_entity_empty_name_shows_clean_error(store: KBStore) -> None:
 def test_show_missing_proposal_shows_clean_error(store: KBStore) -> None:
     result = CliRunner().invoke(cli, ["show", "no-such-proposal"])
     _assert_clean_error(result, "proposal no-such-proposal")
+
+
+def test_search_fts5_backend_label(
+    store: KBStore, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """vouch search prints (fts5) when FTS5 returns hits."""
+    from vouch import index_db
+    from vouch.proposals import approve as do_approve
+    from vouch.proposals import propose_claim
+    src = store.put_source(b"e")
+    pr = propose_claim(store, text="findable token", evidence=[src.id], proposed_by="agent")
+    do_approve(store, pr.id, approved_by="reviewer")
+    # Index only the FTS5 tables directly — no embedding stack needed
+    with index_db.open_db(store.kb_dir) as conn:
+        index_db.index_claim(
+            conn, id="c-findable", text="findable token",
+            type="observation", status="actionable", tags=[],
+        )
+    runner = CliRunner()
+    result = runner.invoke(cli, ["search", "findable"])
+    assert result.exit_code == 0, result.output
+    assert "(fts5)" in result.output
+
+
+def test_search_substring_backend_label(
+    store: KBStore, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """vouch search prints (substring) when FTS5 raises and fallback runs."""
+    from vouch.proposals import approve as do_approve
+    from vouch.proposals import propose_claim
+    src = store.put_source(b"e")
+    pr = propose_claim(store, text="findable token", evidence=[src.id], proposed_by="agent")
+    do_approve(store, pr.id, approved_by="reviewer")
+    # Remove state.db so FTS5 raises and substring fallback runs
+    state_db = store.kb_dir / "state.db"
+    if state_db.exists():
+        state_db.unlink()
+    runner = CliRunner()
+    result = runner.invoke(cli, ["search", "findable"])
+    assert result.exit_code == 0, result.output
+    assert "(substring)" in result.output