[DEV-16658] - Fix fiscal year format

usaspending_api/llm/assistants/filter_search.py

@@ -131,10 +131,11 @@ def _fiscal_year_date_context() -> str:
         current_fy = today.year + 1 if today.month >= 10 else today.year
         return (
             f"\nThe current date is {today.strftime('%m/%d/%Y')}. The current federal fiscal year is "
-            f"FY{current_fy} (the federal fiscal year runs Oct 1 - Sep 30 and is named for the calendar "
-            f"year it ends in, so FY{current_fy} runs 10/01/{current_fy - 1} - 09/30/{current_fy}). "
-            f"Use FY{current_fy} directly as 'this fiscal year' and FY{current_fy - 1} as 'last fiscal "
-            f"year' - do not recompute the fiscal year from the date yourself."
+            f"{current_fy} (the federal fiscal year runs Oct 1 - Sep 30 and is named for the calendar "
+            f"year it ends in, so Fiscal Year {current_fy} runs 10/01/{current_fy - 1} - 09/30/{current_fy}). "
+            f"Use {current_fy} directly as 'this fiscal year' and {current_fy - 1} as 'last fiscal "
+            f"year' - do not recompute the fiscal year from the date yourself. When populating "
+            f"timePeriodFY, use the bare four-digit year (e.g. '{current_fy}'), never the 'FY' prefix."
         )
 
     @cached_property

usaspending_api/llm/models/py_models.py

@@ -1,3 +1,4 @@
+import re
 from typing import Annotated, Any, Callable, Literal
 
 from pydantic import BaseModel, ConfigDict, Field, RootModel, field_validator, model_validator
@@ -469,6 +470,18 @@ def rekey_selected_agencies(cls, value: Any) -> Any:
             rekeyed[key] = agency
         return rekeyed
 
+    @field_validator("timePeriodFY")
+    @classmethod
+    def validate_time_period_fy(cls, value: list[str]) -> list[str]:
+        """Fiscal years must be bare four-digit strings (e.g. '2026'), not 'FY2026'."""
+        invalid = [year for year in value if not re.fullmatch(r"\d{4}", year)]
+        if invalid:
+            raise ValueError(
+                f"Invalid fiscal year(s) in timePeriodFY: {invalid}. Fiscal years must be four-digit strings "
+                "(e.g. '2026'), without a 'FY' prefix."
+            )
+        return value
+
     @field_validator("awardType")
     @classmethod
     def validate_award_type(cls, value: list[str]) -> list[str]:

usaspending_api/llm/tests/integration/test_py_models.py

@@ -541,6 +541,49 @@ def test_recipient_type_accepts_all_valid_types(self):
         assert len(filters.recipientType) == len(all_types)
 
 
+class TestTimePeriodFY:
+    """Tests for the timePeriodFY four-digit-year validation on the Filters model"""
+
+    def test_time_period_fy_default_empty_list(self):
+        filters = Filters()
+
+        assert filters.timePeriodFY == []
+
+    def test_time_period_fy_accepts_four_digit_years(self):
+        filters = Filters(timePeriodFY=["2023", "2024"])
+
+        assert filters.timePeriodFY == ["2023", "2024"]
+
+    def test_time_period_fy_accepts_single_year(self):
+        filters = Filters(timePeriodFY=["2026"])
+
+        assert filters.timePeriodFY == ["2026"]
+
+    def test_time_period_fy_rejects_fy_prefix(self):
+        with pytest.raises(ValidationError) as exc_info:
+            Filters(timePeriodFY=["FY2026"])
+
+        assert "Invalid fiscal year(s)" in str(exc_info.value)
+
+    def test_time_period_fy_rejects_fy_prefix_mixed_with_valid_year(self):
+        with pytest.raises(ValidationError) as exc_info:
+            Filters(timePeriodFY=["2024", "FY2026"])
+
+        assert "FY2026" in str(exc_info.value)
+
+    def test_time_period_fy_rejects_non_four_digit_year(self):
+        with pytest.raises(ValidationError) as exc_info:
+            Filters(timePeriodFY=["26"])
+
+        assert "Invalid fiscal year(s)" in str(exc_info.value)
+
+    def test_time_period_fy_rejects_non_numeric_value(self):
+        with pytest.raises(ValidationError) as exc_info:
+            Filters(timePeriodFY=["this year"])
+
+        assert "Invalid fiscal year(s)" in str(exc_info.value)
+
+
 class TestAwardType:
     """Tests for the awardType single-group validation on the Filters model"""