fix(bedrock): inline http image urls and keep stop on converse for native chat completions

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm/llms/bedrock/chat/chat_completions/transformation.py

@@ -22,6 +22,11 @@ import httpx
 from typing_extensions import assert_never
 
 import litellm
+from litellm.litellm_core_utils.prompt_templates.image_handling import (
+    async_inline_remote_media,
+    convert_url_to_base64,
+    inline_remote_image_urls,
+)
 from litellm.llms.base_llm.chat.transformation import BaseLLMException
 from litellm.llms.bedrock.base_aws_llm import BaseAWSLLM
 from litellm.llms.bedrock.common_utils import BedrockError, split_bedrock_region_path
@@ -40,7 +45,7 @@ REASONING_CLOSE_TAG: Final = "</reasoning>"
 
 CHAT_COMPLETIONS_REFUSED_PARAMS_BY_FAMILY: Final = MappingProxyType(
     {
-        "openai.gpt-5": frozenset(("frequency_penalty", "presence_penalty", "stop", "logprobs", "top_logprobs")),
+        "openai.gpt-5": frozenset(("frequency_penalty", "presence_penalty", "logprobs", "top_logprobs")),
         "openai.gpt-oss": frozenset(("logit_bias",)),
         "xai.": frozenset(("frequency_penalty", "presence_penalty")),
     }
@@ -167,6 +172,48 @@ def split_reasoning_tag(content: str) -> tuple[str | None, str]:
     return reasoning or None, body
 
 
+def _remote_http_url(candidate: object) -> str | None:
+    return candidate if isinstance(candidate, str) and candidate.startswith(("http://", "https://")) else None
+
+
+def _inlined_image_url_part(part: object) -> object:
+    fields: Final = part if isinstance(part, Mapping) else None
+    if fields is None or fields.get("type") != "image_url":
+        return part
+    image_url: Final = fields.get("image_url")
+    image_url_fields: Final = image_url if isinstance(image_url, Mapping) else None
+    url: Final = _remote_http_url(image_url_fields.get("url") if image_url_fields is not None else image_url)
+    if url is None:
+        return part
+    data_url: Final = convert_url_to_base64(url)
+    inlined: Final = {**image_url_fields, "url": data_url} if image_url_fields is not None else data_url
+    return {**fields, "image_url": inlined}  # mutable-ok: json-serialized message part
+
+
+def _inlined_image_url_message(message: AllMessageValues) -> AllMessageValues:
+    content: Final = message.get("content")
+    if not isinstance(content, list):
+        return message
+    inlined_message: Final = {  # mutable-ok: json-serialized message
+        **message,
+        "content": [_inlined_image_url_part(part) for part in content],
+    }
+    return inlined_message  # pyright: ignore[reportReturnType]  # the same message with remote image parts inlined
+
+
+def _with_inlined_remote_image_urls(
+    messages: list[AllMessageValues],
+) -> list[AllMessageValues]:  # mutable-ok: transform_request takes a list
+    """Inline every remote ``image_url`` so AWS never sees the ``http(s)://`` URLs it rejects.
+
+    AWS's native surface only takes inline ``data:`` URLs and S3 URLs where Converse downloaded
+    remote images itself, so the bytes are fetched and inlined here exactly like Converse did.
+    """
+    return [  # mutable-ok: transform_request takes a list
+        _inlined_image_url_message(message) for message in messages
+    ]
+
+
 class BedrockRuntimeChatCompletionsStreamingHandler(OpenAIChatCompletionStreamingHandler):
     """OpenAI chunk parsing plus the ``<reasoning>`` split, tracked per choice index."""
 
@@ -222,6 +269,10 @@ class AmazonBedrockRuntimeChatCompletionsConfig(OpenAILikeChatConfig):
     def custom_llm_provider(self) -> str | None:
         return "bedrock"
 
+    @property
+    def uses_async_transform_request(self) -> bool:
+        return True
+
     def get_error_class(
         self,
         error_message: str,
@@ -325,7 +376,7 @@ class AmazonBedrockRuntimeChatCompletionsConfig(OpenAILikeChatConfig):
     ) -> dict:  # mutable-ok: BaseConfig signature
         return super().transform_request(
             model=split_bedrock_region_path(model)[1],
-            messages=messages,
+            messages=_with_inlined_remote_image_urls(messages),
             optional_params=self._inference_params(optional_params),
             litellm_params=litellm_params,
             headers=headers,
@@ -341,7 +392,7 @@ class AmazonBedrockRuntimeChatCompletionsConfig(OpenAILikeChatConfig):
     ) -> dict:  # mutable-ok: BaseConfig signature
         return await super().async_transform_request(
             model=split_bedrock_region_path(model)[1],
-            messages=messages,
+            messages=await async_inline_remote_media(messages, should_inline=inline_remote_image_urls),
             optional_params=self._inference_params(optional_params),
             litellm_params=litellm_params,
             headers=headers,

litellm/llms/bedrock/common_utils.py

@@ -899,6 +899,7 @@ BEDROCK_CONVERSE_ONLY_REQUEST_KEYS: Final = frozenset(
         "thinking",
         "additionalModelRequestFields",
         "top_k",
+        "stop",
     )
 )
 
@@ -921,7 +922,8 @@ def bedrock_request_needs_converse(model: str, request_params: Mapping[str, obje
     Converse-shaped body keys (``BEDROCK_CONVERSE_ONLY_REQUEST_KEYS``, the Anthropic-style ``thinking``
     block and the ``additionalModelRequestFields`` / ``top_k`` extension params included, which only Converse
     forwards as ``additionalModelRequestFields`` and ``inferenceConfig``) have no field on
-    AWS's native OpenAI surface, operator-owned request metadata is only written onto the Converse body,
+    AWS's native OpenAI surface, ``stop`` stays on Converse where it fails loudly instead of silently
+    stopping hidden reasoning, operator-owned request metadata is only written onto the Converse body,
     function tools (``tools`` or legacy ``functions``) on a model without
     ``supports_bedrock_runtime_chat_completions_tools_with_reasoning`` are rejected there unless
     ``reasoning_effort`` is exactly ``"none"``, and a ``response_format`` goes native only as

tests/unit/llms/bedrock/chat/chat_completions/test_bedrock_chat_completions_transformation.py

@@ -258,11 +258,13 @@ def test_guardrail_config_falls_back_to_converse(local_cost_map, model):
     assert BedrockModelInfo.get_bedrock_route(model, {"guardrailConfig": None}) == "chat_completions"
 
 
-@pytest.mark.parametrize("model", ["openai.gpt-oss-20b-1:0", "us.xai.grok-4.6"])
+@pytest.mark.parametrize(
+    "model", ["openai.gpt-oss-20b-1:0", "us.xai.grok-4.6", "global.openai.gpt-5.6-sol"]
+)
 @pytest.mark.parametrize(
     "request_params",
-    [{"additionalModelRequestFields": {"reasoning_effort": "high"}}, {"top_k": 40}],
-    ids=["additionalModelRequestFields", "top_k"],
+    [{"additionalModelRequestFields": {"reasoning_effort": "high"}}, {"top_k": 40}, {"stop": ["END"]}],
+    ids=["additionalModelRequestFields", "top_k", "stop"],
 )
 def test_converse_extension_params_fall_back_to_converse(local_cost_map, model, request_params):
     assert bedrock_request_needs_converse(model, request_params) is True
@@ -331,6 +333,69 @@ def test_map_openai_params_sends_max_tokens_as_max_completion_tokens():
     assert mapped == {"max_completion_tokens": 64, "temperature": 0.1}
 
 
+HTTPS_IMAGE_URL = "https://example.com/cat.png"
+IMAGE_MESSAGES = [
+    {
+        "role": "user",
+        "content": [
+            {"type": "text", "text": "what is this"},
+            {"type": "image_url", "image_url": HTTPS_IMAGE_URL},
+            {"type": "image_url", "image_url": {"url": HTTPS_IMAGE_URL, "detail": "high"}},
+            {"type": "image_url", "image_url": {"url": "data:image/png;base64,AAA"}},
+            {"type": "image_url", "image_url": {"url": "s3://bucket/key.png"}},
+        ],
+    }
+]
+
+
+def _assert_remote_images_inlined(content):
+    assert content[0] == {"type": "text", "text": "what is this"}
+    assert content[1]["image_url"]["url"] == f"data:image/png;base64,{HTTPS_IMAGE_URL}"
+    assert content[2] == {
+        "type": "image_url",
+        "image_url": {"url": f"data:image/png;base64,{HTTPS_IMAGE_URL}", "detail": "high"},
+    }
+    assert content[3]["image_url"]["url"] == "data:image/png;base64,AAA"
+    assert content[4]["image_url"]["url"] == "s3://bucket/key.png"
+
+
+def test_transform_request_inlines_remote_image_urls(local_cost_map, monkeypatch):
+    import litellm.llms.bedrock.chat.chat_completions.transformation as native_cc
+
+    monkeypatch.setattr(
+        native_cc, "convert_url_to_base64", lambda url: f"data:image/png;base64,{url}"
+    )
+    body = AmazonBedrockRuntimeChatCompletionsConfig().transform_request(
+        model="us.xai.grok-4.6",
+        messages=IMAGE_MESSAGES,
+        optional_params={},
+        litellm_params={},
+        headers={},
+    )
+
+    _assert_remote_images_inlined(body["messages"][0]["content"])
+
+
+async def test_async_transform_request_inlines_remote_image_urls(local_cost_map, monkeypatch):
+    import litellm.litellm_core_utils.prompt_templates.image_handling as image_handling
+
+    async def fake_convert(url):
+        return f"data:image/png;base64,{url}"
+
+    monkeypatch.setattr(image_handling, "async_convert_url_to_base64", fake_convert)
+    cfg = AmazonBedrockRuntimeChatCompletionsConfig()
+    assert cfg.uses_async_transform_request is True
+    body = await cfg.async_transform_request(
+        model="us.xai.grok-4.6",
+        messages=IMAGE_MESSAGES,
+        optional_params={},
+        litellm_params={},
+        headers={},
+    )
+
+    _assert_remote_images_inlined(body["messages"][0]["content"])
+
+
 def test_map_openai_params_keeps_explicit_max_completion_tokens():
     cfg = AmazonBedrockRuntimeChatCompletionsConfig()
     mapped = cfg.map_openai_params(
@@ -398,8 +463,8 @@ def test_supported_params_include_reasoning_effort_for_gpt56(local_cost_map):
     [
         (
             "bedrock/global.openai.gpt-5.6-sol",
-            ("frequency_penalty", "presence_penalty", "stop", "logprobs", "top_logprobs", "n"),
-            ("temperature", "top_p", "logit_bias", "reasoning_effort", "tools", "functions"),
+            ("frequency_penalty", "presence_penalty", "logprobs", "top_logprobs", "n"),
+            ("temperature", "top_p", "logit_bias", "reasoning_effort", "tools", "functions", "stop"),
         ),
         (
             "us.xai.grok-4.6",