test: serve test media from our own fixtures instead of third-party hosts

A dozen tests downloaded their image, audio, or document from someone else's
web server: pexels, pinterest, gratisography, squarespace, dummyimage, arxiv,
wikimedia, w3.org, cmu.edu, and a placeholder service that has since shut down.
That makes a run depend on hosts we do not control, and on assets we have no
right to redistribute. It also fails for reasons that have nothing to do with
litellm: the Bedrock vision e2e went red last week on a Wikimedia 429.

tests/fixtures now holds media we generated ourselves, with the drawing code in
its README so anyone can regenerate it: a 100x100 PNG and JPEG, a one-page PDF,
a markdown file, a csv, and a short spoken wav. Tests that only need bytes read
the file. Tests that have to exercise a real URL fetch (convert_url_to_base64,
Bedrock's document and image embedding, Gemini's tool-result media) take the new
asset_base_url fixture, which serves tests/fixtures over loopback and adds its
own host to user_url_allowed_hosts so litellm's SSRF guard lets it through.

Two of these tests got stronger on the way past. test_convert_tool_response_with_url_image
wrapped its whole body in `except Exception: pytest.skip(...)`, which swallowed
assertion failures as well as download failures, so it could not fail; it now
runs for real and checks the inlined bytes and mime type. test_gpt_vision_token_counting
asserted nothing at all and now checks that the image adds tokens over the same
prompt without it. test_vision_with_custom_model compares against the image the
test actually sent rather than a pasted base64 literal.

test_bedrock_document_understanding traded its .xls case for a .csv, since we
can author a csv and cannot author a legacy .xls; both are Bedrock document
formats, so the coverage is the same shape.

What is left, and why: the tests where the provider fetches the URL rather than
litellm (base_llm_unit_tests' image_url and pdf file_id cases, the Vertex pdf
pass-through, the AssemblyAI passthrough) cannot point at loopback. Those
already reference content we own, through jsdelivr or our own S3 buckets.
Moving them off third-party CDNs needs a public host we control, which is a
separate decision.

tests/fixtures/README.md

@@ -0,0 +1,23 @@
+# tests/fixtures
+
+Media the test suite feeds to litellm, generated by us and committed here so no
+test depends on a third-party host staying up or on someone else's copyright.
+
+- `test_image.png` / `test_image.jpg`: a 100x100 square with two diagonal lines,
+  drawn in code (see the snippet below). Any test that just needs valid image
+  bytes should use one of these.
+
+```python
+from PIL import Image, ImageDraw
+
+img = Image.new("RGB", (100, 100), (255, 255, 255))
+d = ImageDraw.Draw(img)
+d.rectangle([10, 10, 89, 89], outline=(17, 17, 17), width=4)
+d.line([10, 10, 89, 89], fill=(200, 30, 30), width=4)
+d.line([89, 10, 10, 89], fill=(30, 80, 200), width=4)
+img.save("test_image.png", "PNG", optimize=True)
+img.save("test_image.jpg", "JPEG", quality=85, optimize=True)
+```
+
+`asset_server.py` serves this directory over HTTP on loopback, for the tests that
+have to exercise a real URL fetch rather than a `data:` URL

tests/fixtures/asset_server.py

@@ -0,0 +1,52 @@
+"""Serves tests/fixtures over loopback HTTP.
+
+Some code paths under test (``convert_url_to_base64``, Bedrock's image
+embedding, Gemini's tool-result media handling) only run when the image arrives
+as a URL, so a ``data:`` URL would skip the very branch being tested. Those
+tests point at this server instead of a third-party image host.
+
+litellm's SSRF guard rejects loopback by default, so the server also adds its
+own host to ``litellm.user_url_allowed_hosts`` for as long as it is up: the
+same setting an operator uses to reach an internal image host.
+"""
+
+from __future__ import annotations
+
+import threading
+from functools import partial
+from http.server import SimpleHTTPRequestHandler, ThreadingHTTPServer
+from pathlib import Path
+from typing import Iterator
+
+import litellm
+
+ASSETS_DIR = Path(__file__).parent
+TEST_IMAGE_PNG = ASSETS_DIR / "test_image.png"
+TEST_IMAGE_JPG = ASSETS_DIR / "test_image.jpg"
+TEST_SPEECH_WAV = ASSETS_DIR / "test_speech.wav"
+TEST_DOCUMENT_PDF = ASSETS_DIR / "test_document.pdf"
+TEST_DOCUMENT_MD = ASSETS_DIR / "test_document.md"
+TEST_TABLE_CSV = ASSETS_DIR / "test_table.csv"
+
+
+class _QuietHandler(SimpleHTTPRequestHandler):
+    def log_message(self, *args: object) -> None:
+        pass
+
+
+def serve_assets() -> Iterator[str]:
+    server = ThreadingHTTPServer(
+        ("127.0.0.1", 0), partial(_QuietHandler, directory=str(ASSETS_DIR))
+    )
+    host = f"127.0.0.1:{server.server_address[1]}"
+    thread = threading.Thread(target=server.serve_forever, daemon=True)
+    thread.start()
+    previously_allowed = litellm.user_url_allowed_hosts
+    litellm.user_url_allowed_hosts = [*previously_allowed, host]
+    try:
+        yield f"http://{host}"
+    finally:
+        litellm.user_url_allowed_hosts = previously_allowed
+        server.shutdown()
+        server.server_close()
+        thread.join(timeout=5)

tests/fixtures/test_document.md

@@ -0,0 +1,6 @@
+# LiteLLM test document
+
+This file exists so the test suite can send a Markdown document without
+downloading one from someone else's web server.
+
+The quick brown fox jumps over the lazy dog.

tests/fixtures/test_document.pdf

@@ -0,0 +1,42 @@
+%PDF-1.4
+1 0 obj
+<< /Type /Catalog /Pages 2 0 R >>
+endobj
+2 0 obj
+<< /Type /Pages /Kids [3 0 R] /Count 1 >>
+endobj
+3 0 obj
+<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] /Resources << /Font << /F1 4 0 R >> >> /Contents 5 0 R >>
+endobj
+4 0 obj
+<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>
+endobj
+5 0 obj
+<< /Length 255 >>
+stream
+BT
+/F1 14 Tf
+72 720 Td
+18 TL
+(LiteLLM test document) Tj T*
+() Tj T*
+(This file exists so the test suite can send a PDF without) Tj T*
+(downloading one from someone else's web server.) Tj T*
+() Tj T*
+(The quick brown fox jumps over the lazy dog.) Tj T*
+ET
+endstream
+endobj
+xref
+0 6
+0000000000 65535 f 
+0000000009 00000 n 
+0000000058 00000 n 
+0000000115 00000 n 
+0000000241 00000 n 
+0000000311 00000 n 
+trailer
+<< /Size 6 /Root 1 0 R >>
+startxref
+616
+%%EOF

tests/fixtures/test_table.csv

@@ -0,0 +1,5 @@
+region,quarter,revenue
+north,Q1,1200
+north,Q2,1450
+south,Q1,980
+south,Q2,1130

tests/litellm_utils_tests/test_utils.py

@@ -1124,14 +1124,10 @@ def test_usage_object_null_tokens():
 def test_is_base64_encoded():
     import base64
 
-    import requests
+    from tests.fixtures.asset_server import TEST_IMAGE_PNG
 
     litellm.set_verbose = True
-    url = "https://dummyimage.com/100/100/fff&text=Test+image"
-    response = requests.get(url)
-    file_data = response.content
-
-    encoded_file = base64.b64encode(file_data).decode("utf-8")
+    encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
     base64_image = f"data:image/png;base64,{encoded_file}"
 
     from litellm.utils import is_base64_encoded

tests/llm_translation/base_embedding_unit_tests.py

@@ -16,17 +16,13 @@ from litellm.utils import (
     get_optional_params,
     get_optional_params_embeddings,
 )
-import requests
 import base64
 
-# test_example.py
 from abc import ABC, abstractmethod
 
-url = "https://dummyimage.com/100/100/fff&text=Test+image"
-response = requests.get(url)
-file_data = response.content
+from tests.fixtures.asset_server import TEST_IMAGE_PNG
 
-encoded_file = base64.b64encode(file_data).decode("utf-8")
+encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
 base64_image = f"data:image/png;base64,{encoded_file}"
 
 

tests/llm_translation/base_llm_unit_tests.py

@@ -30,6 +30,7 @@ from openai import OpenAI
 sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..")))
 
 from tests._live_test_helpers import _skip_live_prompt_caching_test  # noqa: E402
+from tests.fixtures.asset_server import TEST_SPEECH_WAV  # noqa: E402
 
 
 def _usage_format_tests(usage: litellm.Usage):
@@ -758,11 +759,7 @@ class BaseLLMChatTest(ABC):
                 f"Model={base_completion_call_args['model']} does not support audio input"
             )
 
-        url = "https://openaiassets.blob.core.windows.net/$web/API/docs/audio/alloy.wav"
-        response = httpx.get(url)
-        response.raise_for_status()
-        wav_data = response.content
-        encoded_string = base64.b64encode(wav_data).decode("utf-8")
+        encoded_string = base64.b64encode(TEST_SPEECH_WAV.read_bytes()).decode("utf-8")
 
         completion = self.completion_function(
             **base_completion_call_args,
@@ -1274,12 +1271,8 @@ class BaseLLMChatTest(ABC):
             print("Model does not support audio input")
             pytest.skip("Model does not support audio input")
 
-        url = "https://openaiassets.blob.core.windows.net/$web/API/docs/audio/alloy.wav"
-        response = httpx.get(url)
-        response.raise_for_status()
-        wav_data = response.content
         audio_format = "wav"
-        encoded_string = base64.b64encode(wav_data).decode("utf-8")
+        encoded_string = base64.b64encode(TEST_SPEECH_WAV.read_bytes()).decode("utf-8")
 
         audio_content = [{"type": "text", "text": "What is in this recording?"}]
 

tests/llm_translation/conftest.py

@@ -27,6 +27,12 @@ from tests._vcr_conftest_common import (  # noqa: E402,F401
     vcr_config_dict,
 )
 from tests.fake_openai_endpoint import ensure_fake_openai_endpoint  # noqa: E402
+from tests.fixtures.asset_server import serve_assets  # noqa: E402
+
+
+@pytest.fixture
+def asset_base_url():
+    yield from serve_assets()
 
 
 @pytest.fixture(scope="session", autouse=True)

tests/llm_translation/test_bedrock_completion.py

@@ -2441,7 +2441,7 @@ class TestBedrockEmbedding(BaseLLMEmbeddingTest):
 
 
 @pytest.mark.asyncio
-async def test_bedrock_image_url_sync_client():
+async def test_bedrock_image_url_sync_client(asset_base_url):
     from litellm.llms.custom_httpx.http_handler import AsyncHTTPHandler
     import logging
     from litellm import verbose_logger
@@ -2459,7 +2459,7 @@ async def test_bedrock_image_url_sync_client():
                 {
                     "type": "image_url",
                     "image_url": {
-                        "url": "https://awsmp-logos.s3.amazonaws.com/seller-xw5kijmvmzasy/c233c9ade2ccb5491072ae232c814942.png"
+                        "url": f"{asset_base_url}/test_image.png"
                     },
                 },
             ],
@@ -2523,18 +2523,12 @@ def test_bedrock_error_handling_streaming(exception_type, expected_status_code):
 
 
 @pytest.mark.parametrize(
-    "image_url",
-    [
-        "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf",
-        # "https://raw.githubusercontent.com/datasets/gdp/master/data/gdp.csv",
-        "https://www.cmu.edu/blackboard/files/evaluate/tests-example.xls",
-        # "https://raw.githubusercontent.com/datasets/sample-data/master/README.txt", # invalid url
-        "https://raw.githubusercontent.com/mdn/content/main/README.md",
-    ],
+    "asset_name",
+    ["test_document.pdf", "test_table.csv", "test_document.md"],
 )
 @pytest.mark.flaky(retries=6, delay=2)
 @pytest.mark.asyncio
-async def test_bedrock_document_understanding(image_url):
+async def test_bedrock_document_understanding(asset_name, asset_base_url):
     from litellm import acompletion
 
     litellm._turn_on_debug()
@@ -2544,7 +2538,7 @@ async def test_bedrock_document_understanding(image_url):
         {"type": "text", "text": f"What's this file about?"},
         {
             "type": "image_url",
-            "image_url": image_url,
+            "image_url": f"{asset_base_url}/{asset_name}",
         },
     ]
 

tests/llm_translation/test_gpt4o_audio.py

@@ -11,7 +11,8 @@ import litellm
 from litellm import Choices, Message, ModelResponse
 from litellm.types.utils import StreamingChoices, ChatCompletionAudioResponse
 import base64
-import requests
+
+from tests.fixtures.asset_server import TEST_SPEECH_WAV
 
 
 def check_non_streaming_response(completion):
@@ -88,17 +89,12 @@ async def test_audio_output_from_model(stream):
 @pytest.mark.parametrize("stream", [True, False])
 @pytest.mark.parametrize("model", ["gpt-audio-1.5"])
 async def test_audio_input_to_model(stream, model):
-    # Fetch the audio file and convert it to a base64 encoded string
     audio_format = "pcm16"
     if stream is False:
         audio_format = "wav"
     litellm._turn_on_debug()
     litellm.drop_params = True
-    url = "https://openaiassets.blob.core.windows.net/$web/API/docs/audio/alloy.wav"
-    response = requests.get(url)
-    response.raise_for_status()
-    wav_data = response.content
-    encoded_string = base64.b64encode(wav_data).decode("utf-8")
+    encoded_string = base64.b64encode(TEST_SPEECH_WAV.read_bytes()).decode("utf-8")
     try:
         completion = await litellm.acompletion(
             model=model,

tests/llm_translation/test_openai.py

@@ -209,19 +209,16 @@ async def test_vision_with_custom_model():
 
     """
     import base64
-    import requests
     from openai import AsyncOpenAI
 
+    from tests.fixtures.asset_server import TEST_IMAGE_PNG
+
     client = AsyncOpenAI(api_key="fake-api-key")
 
     litellm.set_verbose = True
     api_base = "https://my-custom.api.openai.com"
 
-    # Fetch and encode a test image
-    url = "https://dummyimage.com/100/100/fff&text=Test+image"
-    response = requests.get(url)
-    file_data = response.content
-    encoded_file = base64.b64encode(file_data).decode("utf-8")
+    encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
     base64_image = f"data:image/png;base64,{encoded_file}"
 
     with patch.object(
@@ -261,9 +258,7 @@ async def test_vision_with_custom_model():
                     {"type": "text", "text": "What's in this image?"},
                     {
                         "type": "image_url",
-                        "image_url": {
-                            "url": "data:image/png;base64,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"
-                        },
+                        "image_url": {"url": base64_image},
                     },
                 ],
             },
@@ -473,7 +468,7 @@ class TestOpenAIGPT4OAudioTranscription(BaseLLMAudioTranscriptionTest):
 
 @pytest.mark.asyncio
 @pytest.mark.parametrize("model", ["gpt-4o"])
-async def test_openai_pdf_url(model):
+async def test_openai_pdf_url(model, asset_base_url):
     from litellm.utils import return_raw_request, CallTypes
 
     request = return_raw_request(
@@ -487,7 +482,9 @@ async def test_openai_pdf_url(model):
                         {"type": "text", "text": "What is the first page of the PDF?"},
                         {
                             "type": "file",
-                            "file": {"file_id": "https://arxiv.org/pdf/2303.08774"},
+                            "file": {
+                                "file_id": f"{asset_base_url}/test_document.pdf"
+                            },
                         },
                     ],
                 }

tests/llm_translation/test_prompt_factory.py

@@ -181,10 +181,8 @@ def test_bedrock_tool_calling_pt():
     print(converted_tools)
 
 
-def test_convert_url_to_img():
-    response_url = convert_url_to_base64(
-        url="https://images.pexels.com/photos/1319515/pexels-photo-1319515.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1"
-    )
+def test_convert_url_to_img(asset_base_url):
+    response_url = convert_url_to_base64(url=f"{asset_base_url}/test_image.jpg")
 
     assert "image/jpeg" in response_url
 
@@ -1289,17 +1287,16 @@ def test_just_system_message():
     assert "bedrock requires at least one non-system message" in str(e.value)
 
 
-def test_convert_generic_image_chunk_to_openai_image_obj():
+def test_convert_generic_image_chunk_to_openai_image_obj(asset_base_url):
     from litellm.litellm_core_utils.prompt_templates.factory import (
         convert_generic_image_chunk_to_openai_image_obj,
         convert_to_anthropic_image_obj,
     )
 
-    url = "https://i.pinimg.com/736x/b4/b1/be/b4b1becad04d03a9071db2817fc9fe77.jpg"
+    url = f"{asset_base_url}/test_image.jpg"
     image_obj = convert_to_anthropic_image_obj(url, format=None)
     url_str = convert_generic_image_chunk_to_openai_image_obj(image_obj)
-    image_obj = convert_to_anthropic_image_obj(url_str, format=None)
-    print(image_obj)
+    assert convert_to_anthropic_image_obj(url_str, format=None) == image_obj
 
 
 def test_hf_chat_template():

tests/local_testing/conftest.py

@@ -49,6 +49,12 @@ from tests._vcr_conftest_common import (  # noqa: E402,F401
     vcr_config_dict,
 )
 from tests.fake_openai_endpoint import ensure_fake_openai_endpoint  # noqa: E402
+from tests.fixtures.asset_server import serve_assets  # noqa: E402
+
+
+@pytest.fixture
+def asset_base_url():
+    yield from serve_assets()
 
 
 @pytest.fixture(scope="session", autouse=True)

tests/local_testing/test_amazing_vertex_completion.py

@@ -2000,16 +2000,12 @@ async def test_vertexai_multimodal_embedding_image_in_input():
 async def test_vertexai_multimodal_embedding_base64image_in_input():
     import base64
 
-    import requests
+    from tests.fixtures.asset_server import TEST_IMAGE_PNG
 
     load_vertex_ai_credentials()
     mock_response = AsyncMock()
 
-    url = "https://dummyimage.com/100/100/fff&text=Test+image"
-    response = requests.get(url)
-    file_data = response.content
-
-    encoded_file = base64.b64encode(file_data).decode("utf-8")
+    encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
     base64_image = f"data:image/png;base64,{encoded_file}"
 
     def return_val():
@@ -4061,7 +4057,7 @@ def test_vertex_ai_gemini_audio_ogg():
                     "content": [
                         {
                             "file": {
-                                "file_id": "https://upload.wikimedia.org/wikipedia/commons/5/5f/En-us-public.ogg"
+                                "file_id": "https://example.com/audio.ogg"
                             },
                             "type": "file",
                         }

tests/local_testing/test_completion.py

@@ -616,14 +616,10 @@ def test_completion_base64(model):
     try:
         import base64
 
-        import requests
+        from tests.fixtures.asset_server import TEST_IMAGE_PNG
 
         litellm.set_verbose = True
-        url = "https://dummyimage.com/100/100/fff&text=Test+image"
-        response = requests.get(url)
-        file_data = response.content
-
-        encoded_file = base64.b64encode(file_data).decode("utf-8")
+        encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
         base64_image = f"data:image/png;base64,{encoded_file}"
         resp = litellm.completion(
             model=model,

tests/local_testing/test_embedding.py

@@ -162,14 +162,10 @@ async def test_together_ai_embedding(model, api_base, api_key, sync_mode):
 # test_openai_azure_embedding_simple()
 import base64
 
-import requests
+from tests.fixtures.asset_server import TEST_IMAGE_PNG
 
 litellm.set_verbose = True
-url = "https://dummyimage.com/100/100/fff&text=Test+image"
-response = requests.get(url)
-file_data = response.content
-
-encoded_file = base64.b64encode(file_data).decode("utf-8")
+encoded_file = base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode("utf-8")
 base64_image = f"data:image/png;base64,{encoded_file}"
 
 

tests/local_testing/test_ollama.py

@@ -75,7 +75,7 @@ def test_ollama_json_mode():
 # test_ollama_json_mode()
 
 
-def test_ollama_vision_model():
+def test_ollama_vision_model(asset_base_url):
     from litellm.llms.custom_httpx.http_handler import HTTPHandler
 
     client = HTTPHandler()
@@ -93,7 +93,7 @@ def test_ollama_vision_model():
                             {
                                 "type": "image_url",
                                 "image_url": {
-                                    "url": "https://dummyimage.com/100/100/fff&text=Test+image"
+                                    "url": f"{asset_base_url}/test_image.png"
                                 },
                             },
                         ],

tests/test_litellm/conftest.py

@@ -39,6 +39,13 @@ from litellm.llms.custom_httpx.async_client_cleanup import (
 )
 from litellm.proxy.db import tool_registry_writer as tool_registry_writer_module
 
+from tests.fixtures.asset_server import serve_assets
+
+
+@pytest.fixture
+def asset_base_url():
+    yield from serve_assets()
+
 
 def _reset_module_level_aws_auth_caches():
     """

tests/test_litellm/litellm_core_utils/test_token_counter.py

@@ -380,7 +380,7 @@ def test_encoding_and_decoding():
 # test_encoding_and_decoding()
 
 
-def test_gpt_vision_token_counting():
+def test_gpt_vision_token_counting(asset_base_url):
     messages = [
         {
             "role": "user",
@@ -388,13 +388,17 @@ def test_gpt_vision_token_counting():
                 {"type": "text", "text": "What’s in this image?"},
                 {
                     "type": "image_url",
-                    "image_url": "https://awsmp-logos.s3.amazonaws.com/seller-xw5kijmvmzasy/c233c9ade2ccb5491072ae232c814942.png",
+                    "image_url": f"{asset_base_url}/test_image.png",
                 },
             ],
         }
     ]
+    text_only_tokens = token_counter(
+        model="gpt-4-vision-preview",
+        messages=[{"role": "user", "content": "What’s in this image?"}],
+    )
     tokens = token_counter(model="gpt-4-vision-preview", messages=messages)
-    print(f"tokens: {tokens}")
+    assert tokens > text_only_tokens
 
 
 # test_gpt_vision_token_counting()

tests/test_litellm/llms/vertex_ai/gemini/test_vertex_ai_gemini_transformation.py

@@ -15,6 +15,8 @@ from litellm.llms.vertex_ai.gemini.transformation import (
 from litellm.types.llms.vertex_ai import BlobType
 from litellm.types.utils import Message
 
+from tests.fixtures.asset_server import TEST_IMAGE_PNG
+
 
 def test_check_if_part_exists_in_parts():
     parts = [
@@ -1669,12 +1671,9 @@ def test_gemini_history_nests_multimodal_tool_response_parts():
     ]
 
 
-def test_convert_tool_response_with_url_image():
+def test_convert_tool_response_with_url_image(asset_base_url):
     """Test tool response with HTTP URL image (will download and convert)."""
-    import pytest
-
-    # Use a publicly accessible test image URL
-    test_image_url = "https://via.placeholder.com/1x1.png"
+    test_image_url = f"{asset_base_url}/test_image.png"
 
     tool_message = {
         "role": "tool",
@@ -1697,30 +1696,23 @@ def test_convert_tool_response_with_url_image():
         ]
     }
 
-    try:
-        result = convert_to_gemini_tool_call_result(
-            tool_message, last_message_with_tool_calls
-        )
+    result = convert_to_gemini_tool_call_result(
+        tool_message, last_message_with_tool_calls
+    )
 
-        assert isinstance(
-            result, list
-        ), "Should return a parts list when media is present"
-        assert len(result) == 1, "Should return one function_response part"
-        result_part = result[0]
-        assert "function_response" in result_part
-        assert "inline_data" not in result_part
-        function_response = result_part["function_response"]
-        assert function_response["name"] == "type_text_at"
+    assert isinstance(result, list), "Should return a parts list when media is present"
+    assert len(result) == 1, "Should return one function_response part"
+    result_part = result[0]
+    assert "function_response" in result_part
+    assert "inline_data" not in result_part
+    function_response = result_part["function_response"]
+    assert function_response["name"] == "type_text_at"
 
-        # Check inline_data is nested under functionResponse.parts.
-        assert "parts" in function_response
-        assert len(function_response["parts"]) == 1
-        inline_data: BlobType = function_response["parts"][0]["inline_data"]
-        assert "data" in inline_data
-        assert "mime_type" in inline_data
-    except Exception as e:
-        # Skip test if URL download fails (no internet connection, etc.)
-        pytest.skip(f"Failed to download image from URL: {e}")
+    assert "parts" in function_response
+    assert len(function_response["parts"]) == 1
+    inline_data: BlobType = function_response["parts"][0]["inline_data"]
+    assert inline_data["data"] == base64.b64encode(TEST_IMAGE_PNG.read_bytes()).decode()
+    assert inline_data["mime_type"] == "image/png"
 
 
 def test_convert_tool_response_text_only():