Merge bf6b89b1cb into e768ad55ce

litellm/images/main.py

@@ -708,6 +708,13 @@ def image_variation(
     return response
 
 
+def _as_image_list(image: FileTypes | list[FileTypes] | None) -> list[FileTypes]:
+    """A missing image stays an empty list so each provider config can reject it on its own terms."""
+    if isinstance(image, list):
+        return image
+    return [] if image is None else [image]
+
+
 @client
 def image_edit(
     image: FileTypes | list[FileTypes] | None = None,
@@ -760,7 +767,7 @@ def image_edit(
         _is_async: Final = kwargs.pop("async_call", False) is True
 
         # add images / or return a single image
-        images: Final = image if isinstance(image, list) else ([image] if image is not None else [])
+        images: Final = _as_image_list(image)
 
         headers_from_kwargs: Final = kwargs.get("headers")
         merged_extra_headers: Final[dict[str, object]] = {}
@@ -962,9 +969,9 @@ def image_edit(
 
 @client
 async def aimage_edit(
-    image: FileTypes | list[FileTypes],
-    model: str,
-    prompt: str,
+    image: FileTypes | list[FileTypes] | None = None,
+    model: str | None = None,
+    prompt: str | None = None,
     mask: str | None = None,
     n: int | None = None,
     quality: str | ImageGenerationRequestQuality | None = None,
@@ -996,13 +1003,20 @@ async def aimage_edit(
         loop: Final = asyncio.get_event_loop()
         kwargs["async_call"] = True
 
+        if model is None:
+            raise litellm.BadRequestError(
+                message="model is required for image edits",
+                model="",
+                llm_provider=custom_llm_provider or "",
+            )
+
         # get custom llm provider so we can use this for mapping exceptions
         if custom_llm_provider is None:
             _, custom_llm_provider, _, _ = litellm.get_llm_provider(
                 model=model, api_base=local_vars.get("base_url", None)
             )
 
-        images: Final = image if isinstance(image, list) else [image]
+        images: Final = _as_image_list(image)
 
         func: Final = partial(
             image_edit,

litellm/llms/azure_ai/image_edit/flux2_transformation.py

@@ -98,11 +98,19 @@ class AzureFoundryFlux2ImageEditConfig(OpenAIImageEditConfig):
             raise ValueError("FLUX 2 image edit requires a prompt.")
 
         if image is None:
-            raise ValueError("FLUX 2 image edit requires an image.")
+            raise litellm.BadRequestError(
+                message="FLUX 2 image edit requires an image.",
+                model=model,
+                llm_provider="azure_ai",
+            )
 
         images: Final = tuple(image) if isinstance(image, list) else (image,)
         if not images:
-            raise ValueError("FLUX 2 image edit requires at least one image.")
+            raise litellm.BadRequestError(
+                message="FLUX 2 image edit requires at least one image.",
+                model=model,
+                llm_provider="azure_ai",
+            )
         max_reference_images: Final = 10 if "flex" in model.lower() else 8
         if len(images) > max_reference_images:
             raise ValueError(f"{model} supports at most {max_reference_images} reference images.")

litellm/llms/bedrock/image_edit/amazon_nova_canvas_image_edit_transformation.py

@@ -19,6 +19,7 @@ from typing import TYPE_CHECKING, Any, Final
 import httpx
 
 from litellm._logging import verbose_logger
+from litellm.exceptions import BadRequestError
 from litellm.llms.base_llm.image_edit.transformation import BaseImageEditConfig
 from litellm.llms.bedrock.common_utils import BedrockError
 from litellm.types.images.main import ImageEditOptionalRequestParams
@@ -129,10 +130,14 @@ def _nova_canvas_task_body(
     }
 
 
-def _file_types_to_b64(image: FileTypes | None) -> str:
+def _file_types_to_b64(image: FileTypes | None, model: str) -> str:
     """Encode OpenAI image input to base64 string for Nova Canvas."""
     if image is None:
-        raise ValueError("Nova Canvas image edit requires an image input")
+        raise BadRequestError(
+            message="Nova Canvas image edit requires an image input",
+            model=model,
+            llm_provider="bedrock",
+        )
     if hasattr(image, "read") and callable(getattr(image, "read", None)):
         if hasattr(image, "seek"):
             image.seek(0)
@@ -314,12 +319,12 @@ class BedrockAmazonNovaCanvasImageEditConfig(BaseImageEditConfig):
         headers: dict,
     ) -> tuple[dict, Any]:
         op: Final = dict(image_edit_optional_request_params)
-        image_b64: Final = _file_types_to_b64(image)
+        image_b64: Final = _file_types_to_b64(image, model=model)
 
         mask_raw: Final = op.pop("mask", None)
         mask_b64: str | None = None
         if mask_raw is not None:
-            mask_b64 = _file_types_to_b64(mask_raw)
+            mask_b64 = _file_types_to_b64(mask_raw, model=model)
 
         _size: Final = op.pop("size", None)
         width = op.pop("width", None)

litellm/llms/gemini/image_edit/transformation.py

@@ -6,6 +6,7 @@ from typing import TYPE_CHECKING, Any, Final, cast
 import httpx
 from httpx._types import RequestFiles
 
+from litellm.exceptions import BadRequestError
 from litellm.images.utils import ImageEditRequestUtils
 from litellm.llms.base_llm.image_edit.transformation import BaseImageEditConfig
 from litellm.llms.gemini.common_utils import (
@@ -94,7 +95,11 @@ class GeminiImageEditConfig(BaseImageEditConfig):
     ) -> tuple[dict[str, object], RequestFiles | None]:
         inline_parts: Final = self._prepare_inline_image_parts(image) if image else []
         if not inline_parts:
-            raise ValueError("Gemini image edit requires at least one image.")
+            raise BadRequestError(
+                message="Gemini image edit requires at least one image.",
+                model=model,
+                llm_provider="gemini",
+            )
 
         # Build parts list with image and prompt (if provided)
         parts: Final = inline_parts.copy()

litellm/llms/vertex_ai/image_edit/vertex_gemini_transformation.py

@@ -166,7 +166,11 @@ class VertexAIGeminiImageEditConfig(BaseImageEditConfig, VertexLLM):
     ) -> tuple[dict[str, object], RequestFiles | None]:
         inline_parts: Final = self._prepare_inline_image_parts(image) if image else []
         if not inline_parts:
-            raise ValueError("Vertex AI Gemini image edit requires at least one image.")
+            raise litellm.BadRequestError(
+                message="Vertex AI Gemini image edit requires at least one image.",
+                model=model,
+                llm_provider="vertex_ai",
+            )
 
         # Build parts list with image and prompt (if provided)
         text_parts: Final[list[HttpxPartType]] = [{"text": prompt}] if prompt is not None and prompt != "" else []

tests/test_litellm/images/test_image_edit_missing_image.py

@@ -0,0 +1,51 @@
+"""
+Regression tests for https://github.com/BerriAI/litellm/issues/42185
+
+/v1/images/edits with no `image` part raised a raw TypeError out of aimage_edit,
+which the proxy surfaced as a 500. A 500 tells OpenAI-SDK clients to retry a
+request that can never succeed, so a missing image has to read as a 400.
+"""
+
+import httpx
+import pytest
+
+import litellm
+
+PNG_BYTES: bytes = b"\x89PNG\r\n\x1a\nfakepng"
+
+
+@pytest.mark.asyncio
+async def test_aimage_edit_without_image_is_a_bad_request_not_a_type_error():
+    with pytest.raises(litellm.BadRequestError) as exc_info:
+        await litellm.aimage_edit(
+            model="gemini/gemini-3.1-flash-image",
+            prompt="make it blue",
+            api_key="fake-key-never-used",
+        )
+
+    assert exc_info.value.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_aimage_edit_still_reaches_the_provider_when_an_image_is_supplied(monkeypatch):
+    sent: dict = {}
+
+    async def fake_post(self, *args, **kwargs):
+        sent["json"] = kwargs.get("json")
+        return httpx.Response(
+            200,
+            json={"candidates": [{"content": {"parts": [{"inlineData": {"mimeType": "image/png", "data": "aW1n"}}]}}]},
+            request=httpx.Request("POST", "https://generativelanguage.googleapis.com"),
+        )
+
+    monkeypatch.setattr("litellm.llms.custom_httpx.http_handler.AsyncHTTPHandler.post", fake_post)
+
+    await litellm.aimage_edit(
+        model="gemini/gemini-3.1-flash-image",
+        prompt="make it blue",
+        image=PNG_BYTES,
+        api_key="fake-key-never-used",
+    )
+
+    parts = sent["json"]["contents"][0]["parts"]
+    assert any("inlineData" in part for part in parts)

tests/unit/llms/gemini/image_edit/test_gemini_image_edit_transformation.py

@@ -244,7 +244,9 @@ class TestGeminiImageEditTransformation:
     def test_transform_image_edit_request_without_image_raises(self) -> None:
         optional_params = {}
 
-        with pytest.raises(ValueError, match='Gemini image edit requires at least one image\\.'):
+        with pytest.raises(
+            litellm.BadRequestError, match='Gemini image edit requires at least one image\\.'
+        ) as exc_info:
             self.config.transform_image_edit_request(
                 model=self.model,
                 prompt=self.prompt,
@@ -254,6 +256,8 @@ class TestGeminiImageEditTransformation:
                 headers={},
             )
 
+        assert exc_info.value.status_code == 400
+
     def test_use_multipart_form_data_returns_false(self) -> None:
         """
         Gemini uses JSON requests, not multipart/form-data.

tests/unit/llms/vertex_ai/image_edit/test_vertex_ai_image_edit_transformation.py

@@ -8,6 +8,8 @@ from unittest.mock import MagicMock, patch
 import httpx
 import pytest
 
+import litellm
+
 from litellm.llms.vertex_ai.image_edit.vertex_gemini_transformation import (
     VertexAIGeminiImageEditConfig,
 )
@@ -132,7 +134,7 @@ class TestVertexAIGeminiImageEditTransformation:
         """Test that missing image raises ValueError"""
         optional_params = {}
 
-        with pytest.raises(ValueError, match="requires at least one image"):
+        with pytest.raises(litellm.BadRequestError, match="requires at least one image"):
             self.config.transform_image_edit_request(
                 model=self.model,
                 prompt=self.prompt,