diff --git a/datasette/views/table.py b/datasette/views/table.py
index 190529f4..eb155407 100644
--- a/datasette/views/table.py
+++ b/datasette/views/table.py
@@ -1158,7 +1158,7 @@ def _escape_like(value):
 
 
 # Returns the exclusive upper bound for an indexed prefix search:
-# "abc" -> "abd", so `pk >= "abc" and pk < "abd"` covers "abc%".
+# For example, values beginning with "abc" fall below the next prefix boundary.
 # The LIKE clause is still applied separately for exact escaped-LIKE semantics.
 def _prefix_range_end(value):
     if not value:
@@ -1221,6 +1221,9 @@ def _autocomplete_response_rows(rows, pks, label_column):
     return response_rows
 
 
+AUTOCOMPLETE_TIME_LIMIT_MS = 500
+
+
 class TableAutocompleteView(BaseView):
     name = "table-autocomplete"
 
@@ -1289,7 +1292,9 @@ class TableAutocompleteView(BaseView):
         )
 
         try:
-            results = await db.execute(sql, params, custom_time_limit=500)
+            results = await db.execute(
+                sql, params, custom_time_limit=AUTOCOMPLETE_TIME_LIMIT_MS
+            )
         except QueryInterrupted:
             fallback_where = _autocomplete_prefix_like(pks[0])
             prefix_end = _prefix_range_end(q)
@@ -1312,7 +1317,11 @@ class TableAutocompleteView(BaseView):
                 order_by=_autocomplete_pk_order_by(pks),
             )
             try:
-                results = await db.execute(fallback_sql, params, custom_time_limit=500)
+                results = await db.execute(
+                    fallback_sql,
+                    params,
+                    custom_time_limit=AUTOCOMPLETE_TIME_LIMIT_MS,
+                )
             except QueryInterrupted:
                 return Response.json({"rows": []})
 
diff --git a/docs/introspection.rst b/docs/introspection.rst
index 7702a4b5..4834f441 100644
--- a/docs/introspection.rst
+++ b/docs/introspection.rst
@@ -201,6 +201,15 @@ Search example with ``?q=facet`` returns only items matching ``.*facet.*``:
 
 When multiple search terms are provided (e.g., ``?q=user+profile``), items must match the pattern ``.*user.*profile.*``. Results are ordered by relevance, then by item type and shortest display name.
 
+.. _AutocompleteDebugView:
+
+/-/debug/autocomplete
+---------------------
+
+The debug tool at ``/-/debug/autocomplete`` can be used to try out the autocomplete component against a specific table. Pass ``?database=db&table=table`` to display an autocomplete field backed by that table's ``/-/autocomplete`` endpoint.
+
+Without those query string arguments, the page lists up to five tables with detected label columns, scanning at most 100 tables.
+
 .. _JsonDataView_threads:
 
 /-/threads
diff --git a/tests/test_autocomplete.py b/tests/test_autocomplete.py
index d7d78848..abe19af2 100644
--- a/tests/test_autocomplete.py
+++ b/tests/test_autocomplete.py
@@ -1,6 +1,7 @@
 import pytest
 
 from datasette.app import Datasette
+import datasette.views.table as table_views
 
 
 @pytest.mark.asyncio
@@ -190,7 +191,8 @@ async def test_autocomplete_primary_key_called_label():
 
 
 @pytest.mark.asyncio
-async def test_autocomplete_timeout_uses_prefix_fallback():
+async def test_autocomplete_timeout_uses_prefix_fallback(monkeypatch):
+    monkeypatch.setattr(table_views, "AUTOCOMPLETE_TIME_LIMIT_MS", 1)
     ds = Datasette(
         memory=True,
         config={
@@ -200,7 +202,6 @@ async def test_autocomplete_timeout_uses_prefix_fallback():
         },
         settings={
             "num_sql_threads": 1,
-            "sql_time_limit_ms": 1,
         },
     )
     db = ds.add_memory_database("autocomplete_timeout")