diff --git a/openlibrary/fastapi/search.py b/openlibrary/fastapi/search.py
index 8d4ffedf7cd..0111cb88166 100644
--- a/openlibrary/fastapi/search.py
+++ b/openlibrary/fastapi/search.py
@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 import json
-from typing import Annotated, Any
+from typing import Annotated, Any, Literal
 
 from fastapi import APIRouter, Depends, Query, Request
 from fastapi.responses import JSONResponse
@@ -50,8 +50,8 @@ class PublicQueryOptions(BaseModel):
     person: str | None = None
     time: str | None = None
     # from workscheme facet_fields
-    has_fulltext: bool | None = None
-    public_scan_b: bool | None = None
+    has_fulltext: Literal['true', 'false'] | None = None
+    public_scan_b: Literal['true', 'false'] | None = None
 
     """
     The day will come when someone asks, why do we have Field wrapping Query
diff --git a/openlibrary/tests/fastapi/test_search.py b/openlibrary/tests/fastapi/test_search.py
index 772e7176910..75ba6ac254f 100644
--- a/openlibrary/tests/fastapi/test_search.py
+++ b/openlibrary/tests/fastapi/test_search.py
@@ -189,9 +189,9 @@ def test_pagination_validation_errors(self, client, mock_work_search, params):
         [
             # Case 1: publisher should pass as a string
             ({'publisher': 'Lab of Thought'}, 'publisher', 'Lab of Thought'),
-            # Case 2: has_fulltext should pass as a boolean
-            ({'has_fulltext': 'true'}, 'has_fulltext', True),
-            ({'has_fulltext': 'false'}, 'has_fulltext', False),
+            # Case 2: has_fulltext should pass as a string
+            ({'has_fulltext': 'true'}, 'has_fulltext', 'true'),
+            ({'has_fulltext': 'false'}, 'has_fulltext', 'false'),
         ],
     )
     def test_search_parameter_types(