Repository: stanfordnlp/dspy

Issue:
[Bug] Track Usage not working w/ FastAPI+Bedrock+dspy.Streamify
### What happened?

When using `dspy.settings.configure(track_usage=True)` using a AWS Bedrock model in a FastAPI application and using streaming of the answer, I get the following error:

```python
Exception in thread Thread-1 (producer):
  + Exception Group Traceback (most recent call last):
  |   File "/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/threading.py", line 1075, in _bootstrap_inner
  |     self.run()
  |   File "/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/threading.py", line 1012, in run
  |     self._target(*self._args, **self._kwargs)
  |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/streaming/streamify.py", line 243, in producer
  |     context.run(asyncio.run, runner())
  |   File "/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 194, in run
  |     return runner.run(main)
  |            ^^^^^^^^^^^^^^^^
  |   File "/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/asyncio/runners.py", line 118, in run
  |     return self._loop.run_until_complete(task)
  |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |   File "uvloop/loop.pyx", line 1518, in uvloop.loop.Loop.run_until_complete
  |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/streaming/streamify.py", line 237, in runner
  |     async for item in async_generator:
  |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/streaming/streamify.py", line 177, in async_streamer
  |     async with create_task_group() as tg, send_stream, receive_stream:
  |                ^^^^^^^^^^^^^^^^^^^
  |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/anyio/_backends/_asyncio.py", line 772, in __aexit__
  |     raise BaseExceptionGroup(
  | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)
  +-+---------------- 1 ----------------
    | Traceback (most recent call last):
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/streaming/streamify.py", line 171, in generator
    |     prediction = await program(*args, **kwargs)
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/asyncify.py", line 63, in async_program
    |     return await call_async(*args, **kwargs)
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/asyncer/_main.py", line 382, in wrapper
    |     return await run_sync(
    |            ^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/asyncer/_compat.py", line 24, in run_sync
    |     return await anyio.to_thread.run_sync(
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/anyio/to_thread.py", line 56, in run_sync
    |     return await get_async_backend().run_sync_in_worker_thread(
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/anyio/_backends/_asyncio.py", line 2470, in run_sync_in_worker_thread
    |     return await future
    |            ^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/anyio/_backends/_asyncio.py", line 967, in run
    |     result = context.run(func, *args)
    |              ^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/asyncify.py", line 57, in wrapped_program
    |     return program(*a, **kw)
    |            ^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/callback.py", line 343, in sync_wrapper
    |     raise exception
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/callback.py", line 339, in sync_wrapper
    |     results = fn(instance, *args, **kwargs)
    |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/primitives/program.py", line 29, in __call__
    |     output.set_lm_usage(usage_tracker.get_total_tokens())
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/usage_tracker.py", line 59, in get_total_tokens
    |     total_usage = self._merge_usage_entries(total_usage, usage_entry)
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |   File "/Users/cmeyer/code/dspy_poc/.venv/lib/python3.12/site-packages/dspy/utils/usage_tracker.py", line 45, in _merge_usage_entries
    |     result[k] += v if v else 0
    | TypeError: unsupported operand type(s) for +=: 'dict' and 'int'
    +------------------------------------
```


### Steps to reproduce



Here is my reproductible error:
```python
from dataclasses import asdict

import dspy
import ujson
from dspy.streaming import StatusMessageProvider, StreamListener, StreamResponse, StatusMessage
from fastapi.responses import StreamingResponse
from fastapi import FastAPI, HTTPException
import dspy


class MyStatusMessageProvider(StatusMessageProvider):
    def tool_start_status_message(self, instance, inputs):
        return f"`Pythia is using tool {instance.name}...`"

    def tool_end_status_message(self, outputs):
        return ""

    def lm_start_status_message(self, instance, inputs):
        return "`Pythia is thinking...`"

def evaluate_math(expression: str):
    return dspy.PythonInterpreter({}).execute(expression)

def search_wikipedia(query: str):
    results = dspy.ColBERTv2(url='http://20.102.90.50:2017/wiki17_abstracts')(query, k=3)
    return [x['text'] for x in results]

def streaming_response(streamer):
    """
    Custom streaming response function that handles StatusMessage objects.
    This implements the same functionality as dspy_streaming_response but adds handling for StatusMessage objects.
    """
    from dspy.primitives.prediction import Prediction
    import litellm

    for value in streamer:
        if isinstance(value, StatusMessage):
            data = {"status": value.message}
            yield f"data: {ujson.dumps(data)}\n\n"
        elif isinstance(value, Prediction):
            data = {"prediction": {k: v for k, v in value.items(include_dspy=False)}}
            yield f"data: {ujson.dumps(data)}\n\n"
        elif isinstance(value, litellm.ModelResponseStream):
            data = {"chunk": value.json()}
            yield f"data: {ujson.dumps(data)}\n\n"
        elif isinstance(value, StreamResponse):
            data = {"chunk": {k: v for k, v in asdict(value).items()}}
            yield f"data: {ujson.dumps(data)}\n\n"
        elif isinstance(value, str) and value.startswith("data:"):
            yield value
        else:
            data = {"unknown": str(value)}
            yield f"data: {ujson.dumps(data)}\n\n"
    yield "data: [DONE]\n\n"

app = FastAPI(
    title="DSPy Program API",
    description="A simple API serving a DSPy Chain of Thought program",
    version="1.0.0"
)
# Configure DSPy with LiteLLM
dspy.configure(
    lm=dspy.LM(
        provider="litellm",
        model="bedrock/us.anthropic.claude-3-5-haiku-20241022-v1:0",
        aws_region_name="us-east-1",
        cache=False,
    )
)
dspy.settings.configure(track_usage=True)
react = dspy.ReAct("question -> answer: str", tools=[evaluate_math, search_wikipedia])

dspy_streamer = dspy.streamify(
    react,
    status_message_provider=MyStatusMessageProvider(),
    stream_listeners=[
        StreamListener(signature_field_name="reasoning"),
        StreamListener(signature_field_name="answer"),
    ],
    async_streaming=False,
)

@app.post("/predict")
def predict():
    stream = dspy_streamer(question="What is 9362158 divided by the year of birth of David Gregory of Kinnairdy castle?")
    return StreamingResponse(streaming_response(stream), media_type="text/event-stream")
```

I might do some more testing with other provider or without streaming

Result of more testing cases:
❌ FastAPI + Bedrock + dspy.streamify
✅ FastAPI + OpenAI + dspy.streamify
✅ FastAPI + Bedrock (without streaming)
✅ Bedrock + dspy.streamify (simple script without API)


### DSPy version

2.6.24

Discussion:
@lambda-science: **MORE INFO:**

This issue is **NOT** happening when we don't use `dspy.streamify`.

This is working:
```python
@app.post("/predict")
def predict():
    # stream = dspy_streamer(question="What is 9362158 divided by the year of birth of David Gregory of Kinnairdy castle?")
    # return StreamingResponse(streaming_response(stream), media_type="text/event-stream")
    result = react(question="What is 9362158 divided by the year of birth of David Gregory of Kinnairdy castle?")
    return {
        "status": "success",
        "data": result.toDict(),
        "usage": result.get_lm_usage()
    }
```@lambda-science: **MORE INFO:**

The issue is still happening when converting FastAPI endpoint to an async endpoint with streaming. So it's not related to FastAPI sync/async
```python
dspy_streamer = dspy.asyncify(dspy_streamer)

@app.post("/predict")
async def predict():
    stream = await dspy_streamer(question="What is 9362158 divided by the year of birth of David Gregory of Kinnairdy castle?")
    return StreamingResponse(streaming_response(stream), media_type="text/event-stream")

```
Results in the same error.@lambda-science: **MORE INFO:**

Thie issue is **NOT** happening when using OpenAI provider by replace the LM by:
```python
dspy.configure(
    lm=dspy.LM('openai/gpt-4o-mini', api_key="xxxxx",
    cache=False,
    )
)
```@lambda-science: **To sum-up:**
❌ FastAPI + Bedrock + dspy.streamify
✅ FastAPI + OpenAI + dspy.streamify
✅ FastAPI + Bedrock (without streaming)
✅ Bedrock + dspy.streamify (simple script without API)@lambda-science: AI Generated Monkey-Patch that solved my issue:
```python
from typing import Any


def fixed_merge_usage_entries(self, usage_entry1, usage_entry2) -> dict[str, dict[str, Any]]:
    if usage_entry1 is None or len(usage_entry1) == 0:
        return dict(usage_entry2)
    if usage_entry2 is None or len(usage_entry2) == 0:
        return dict(usage_entry1)

    result = dict(usage_entry2)
    for k, v in usage_entry1.items():
        if k in result:
            if isinstance(v, dict):
                if isinstance(result[k], dict):
                    result[k] = self._merge_usage_entries(result[k], v)
                else:
                    # If v is a dict but result[k] is not, replace result[k] with v
                    result[k] = dict(v)
            else:
                if isinstance(result[k], dict):
                    # If v is not a dict but result[k] is, keep result[k] as is
                    continue
                else:
                    # Both are scalar values, add them
                    result[k] = result[k] or 0
                    v_value = v if v is not None else 0
                    result[k] += v_value
        else:
            # Key doesn't exist in result, just copy it over
            result[k] = v
    return result

from dspy.utils.usage_tracker import UsageTracker
UsageTracker._merge_usage_entries = types.MethodType(fixed_merge_usage_entries, UsageTracker)
```@chenmoneygithub: @lambda-science Thanks for the detailed issue report! Looks like Bedrock can have None as the value, while most other providers sets a default value.@BTripp1986: @lambda-science Is this fully working for you now? I have a DSPy application  served by FastAPI and I get full usage when using sync non-streaming modules, but if I use dspy.streamify() on my app within an async context I only get completion_tokens but no prompt_tokens, and therefor total_tokens is equal to completion_tokens.

I've walked through the LiteLLM code in the debugger and I can see that all usage fields are being set, but at some point in the chunk iterator it seems that they are getting stripped. The LiteLLM code is way too dense and indirect for me to follow exactly where that is happening though.
The interesting thing is that while walking through LiteLLM code all of the usage fields looked right, total_tokens was the sum of prompt and completion tokens, which tells me that it's getting re-computed at some point.

This is happening with both Nova and Claude models in Bedrock.@lambda-science: > [@lambda-science](https://github.com/lambda-science) Is this fully working for you now? I have a DSPy application served by FastAPI and I get full usage when using sync non-streaming modules, but if I use dspy.streamify() on my app within an async context I only get completion_tokens but no prompt_tokens, and therefor total_tokens is equal to completion_tokens.
> 
> I've walked through the LiteLLM code in the debugger and I can see that all usage fields are being set, but at some point in the chunk iterator it seems that they are getting stripped. The LiteLLM code is way too dense and indirect for me to follow exactly where that is happening though. The interesting thing is that while walking through LiteLLM code all of the usage fields looked right, total_tokens was the sum of prompt and completion tokens, which tells me that it's getting re-computed at some point.
> 
> This is happening with both Nova and Claude models in Bedrock.

I didn't remove my monkey_patch yet with the new version, I'll try later on@BTripp1986: I tried adding your monkey patch and I still don't see the missing tokens. I'm interested to see if this works for you. If it does then there may have been a regression when promoting to v3b.

I've notices that the mentioned fields are missing by the time we call any of the UsageTracker methods like `_merge_usage_entries`@lambda-science: > [@lambda-science](https://github.com/lambda-science) Is this fully working for you now? I have a DSPy application served by FastAPI and I get full usage when using sync non-streaming modules, but if I use dspy.streamify() on my app within an async context I only get completion_tokens but no prompt_tokens, and therefor total_tokens is equal to completion_tokens.
> 
> I've walked through the LiteLLM code in the debugger and I can see that all usage fields are being set, but at some point in the chunk iterator it seems that they are getting stripped. The LiteLLM code is way too dense and indirect for me to follow exactly where that is happening though. The interesting thing is that while walking through LiteLLM code all of the usage fields looked right, total_tokens was the sum of prompt and completion tokens, which tells me that it's getting re-computed at some point.
> 
> This is happening with both Nova and Claude models in Bedrock.

Lol you're right i just checked and I get 0 prompt token now but it was working with my monkey patch and v2.7

![Image](https://github.com/user-attachments/assets/44290e5d-d499-4cb4-baf9-b44fc9e6077b)


Solution patch:
diff --git a/dspy/adapters/chat_adapter.py b/dspy/adapters/chat_adapter.py
index 5d5f2400..97bb173c 100644
--- a/dspy/adapters/chat_adapter.py
+++ b/dspy/adapters/chat_adapter.py
@@ -141,12 +141,14 @@ class ChatAdapter(Adapter):
         outputs: dict[str, Any],
         missing_field_message=None,
     ) -> str:
-        return self.format_field_with_value(
+        assistant_message_content = self.format_field_with_value(
             {
                 FieldInfoWithName(name=k, info=v): outputs.get(k, missing_field_message)
                 for k, v in signature.output_fields.items()
             },
         )
+        assistant_message_content += "\n\n[[ ## completed ## ]]\n"
+        return assistant_message_content
 
     def parse(self, signature: Type[Signature], completion: str) -> dict[str, Any]:
         sections = [(None, [])]
diff --git a/dspy/adapters/types/audio.py b/dspy/adapters/types/audio.py
index 800017e7..b4637a06 100644
--- a/dspy/adapters/types/audio.py
+++ b/dspy/adapters/types/audio.py
@@ -44,10 +44,10 @@ class Audio(BaseType):
     @classmethod
     def validate_input(cls, values: Any) -> Any:
         """
-        Validate input for Audio, expecting 'data' and 'format' keys in dictionary.
+        Validate input for Audio, expecting 'data' and 'audio_format' keys in dictionary.
         """
         if isinstance(values, cls):
-            return {"data": values.data, "format": values.format}
+            return {"data": values.data, "audio_format": values.audio_format}
         return encode_audio(values)
 
     @classmethod
@@ -62,7 +62,7 @@ class Audio(BaseType):
             raise ValueError(f"Unsupported MIME type for audio: {mime_type}")
         audio_format = mime_type.split("/")[1]
         encoded_data = base64.b64encode(response.content).decode("utf-8")
-        return cls(data=encoded_data, format=audio_format)
+        return cls(data=encoded_data, audio_format=audio_format)
 
     @classmethod
     def from_file(cls, file_path: str) -> "Audio":
@@ -81,7 +81,7 @@ class Audio(BaseType):
 
         audio_format = mime_type.split("/")[1]
         encoded_data = base64.b64encode(file_data).decode("utf-8")
-        return cls(data=encoded_data, format=audio_format)
+        return cls(data=encoded_data, audio_format=audio_format)
 
     @classmethod
     def from_array(
@@ -102,44 +102,44 @@ class Audio(BaseType):
             subtype="PCM_16",
         )
         encoded_data = base64.b64encode(byte_buffer.getvalue()).decode("utf-8")
-        return cls(data=encoded_data, format=format)
+        return cls(data=encoded_data, audio_format=format)
 
     def __str__(self) -> str:
         return self.serialize_model()
 
     def __repr__(self) -> str:
         length = len(self.data)
-        return f"Audio(data=<AUDIO_BASE_64_ENCODED({length})>, format='{self.audio_format}')"
+        return f"Audio(data=<AUDIO_BASE_64_ENCODED({length})>, audio_format='{self.audio_format}')"
 
 def encode_audio(audio: Union[str, bytes, dict, "Audio", Any], sampling_rate: int = 16000, format: str = "wav") -> dict:
     """
-    Encode audio to a dict with 'data' and 'format'.
+    Encode audio to a dict with 'data' and 'audio_format'.
     
     Accepts: local file path, URL, data URI, dict, Audio instance, numpy array, or bytes (with known format).
     """
-    if isinstance(audio, dict) and "data" in audio and "format" in audio:
+    if isinstance(audio, dict) and "data" in audio and "audio_format" in audio:
         return audio
     elif isinstance(audio, Audio):
-        return {"data": audio.data, "format": audio.format}
+        return {"data": audio.data, "audio_format": audio.audio_format}
     elif isinstance(audio, str) and audio.startswith("data:audio/"):
         try:
             header, b64data = audio.split(",", 1)
             mime = header.split(";")[0].split(":")[1]
             audio_format = mime.split("/")[1]
-            return {"data": b64data, "format": audio_format}
+            return {"data": b64data, "audio_format": audio_format}
         except Exception as e:
             raise ValueError(f"Malformed audio data URI: {e}")
     elif isinstance(audio, str) and os.path.isfile(audio):
         a = Audio.from_file(audio)
-        return {"data": a.data, "format": a.format}
+        return {"data": a.data, "audio_format": a.audio_format}
     elif isinstance(audio, str) and audio.startswith("http"):
         a = Audio.from_url(audio)
-        return {"data": a.data, "format": a.format}
+        return {"data": a.data, "audio_format": a.audio_format}
     elif SF_AVAILABLE and hasattr(audio, "shape"):
         a = Audio.from_array(audio, sampling_rate=sampling_rate, format=format)
-        return {"data": a.data, "format": a.format}
+        return {"data": a.data, "audio_format": a.audio_format}
     elif isinstance(audio, bytes):
         encoded = base64.b64encode(audio).decode("utf-8")
-        return {"data": encoded, "format": format}
+        return {"data": encoded, "audio_format": format}
     else:
         raise ValueError(f"Unsupported type for encode_audio: {type(audio)}")
diff --git a/dspy/adapters/types/tool.py b/dspy/adapters/types/tool.py
index b17cabd6..71008d34 100644
--- a/dspy/adapters/types/tool.py
+++ b/dspy/adapters/types/tool.py
@@ -6,6 +6,7 @@ from jsonschema import ValidationError, validate
 from pydantic import BaseModel, TypeAdapter, create_model
 
 from dspy.adapters.types.base_type import BaseType
+from dspy.dsp.utils.settings import settings
 from dspy.utils.callback import with_callbacks
 
 if TYPE_CHECKING:
@@ -160,12 +161,26 @@ class Tool(BaseType):
             },
         }
 
+    def _run_async_in_sync(self, coroutine):
+        try:
+            loop = asyncio.get_running_loop()
+        except RuntimeError:
+            return asyncio.run(coroutine)
+
+        return loop.run_until_complete(coroutine)
+
     @with_callbacks
     def __call__(self, **kwargs):
         parsed_kwargs = self._validate_and_parse_args(**kwargs)
         result = self.func(**parsed_kwargs)
         if asyncio.iscoroutine(result):
-            raise ValueError("You are calling `__call__` on an async tool, please use `acall` instead.")
+            if settings.allow_tool_async_sync_conversion:
+                return self._run_async_in_sync(result)
+            else:
+                raise ValueError(
+                    "You are calling `__call__` on an async tool, please use `acall` instead or set "
+                    "`allow_async=True` to run the async tool in sync mode."
+                )
         return result
 
     @with_callbacks
diff --git a/dspy/dsp/utils/settings.py b/dspy/dsp/utils/settings.py
index fd7ce52f..fc0f7300 100644
--- a/dspy/dsp/utils/settings.py
+++ b/dspy/dsp/utils/settings.py
@@ -27,6 +27,8 @@ DEFAULT_CONFIG = dotdict(
     provide_traceback=False,  # Whether to include traceback information in error logs.
     num_threads=8,  # Number of threads to use for parallel processing.
     max_errors=10,  # Maximum errors before halting operations.
+    # If true, async tools can be called in sync mode by getting converted to sync.
+    allow_tool_async_sync_conversion=False,
 )
 
 # Global base configuration and owner tracking
diff --git a/dspy/predict/react.py b/dspy/predict/react.py
index cc2a8a02..9b19482b 100644
--- a/dspy/predict/react.py
+++ b/dspy/predict/react.py
@@ -1,5 +1,5 @@
 import logging
-from typing import Any, Callable, Literal
+from typing import TYPE_CHECKING, Any, Callable, Literal, Type
 
 from litellm import ContextWindowExceededError
 
@@ -10,11 +10,33 @@ from dspy.signatures.signature import ensure_signature
 
 logger = logging.getLogger(__name__)
 
+if TYPE_CHECKING:
+    from dspy.signatures.signature import Signature
+
 
 class ReAct(Module):
-    def __init__(self, signature, tools: list[Callable], max_iters=5):
+    def __init__(self, signature: Type["Signature"], tools: list[Callable], max_iters: int = 10):
         """
-        `tools` is either a list of functions, callable classes, or `dspy.Tool` instances.
+        ReAct stands for "Reasoning and Acting," a popular paradigm for building tool-using agents.
+        In this approach, the language model is iteratively provided with a list of tools and has
+        to reason about the current situation. The model decides whether to call a tool to gather more
+        information or to finish the task based on its reasoning process. The DSPy version of ReAct is
+        generalized to work over any signature, thanks to signature polymorphism.
+
+        Args:
+            signature: The signature of the module, which defines the input and output of the react module.
+            tools (list[Callable]): A list of functions, callable objects, or `dspy.Tool` instances.
+            max_iters (Optional[int]): The maximum number of iterations to run. Defaults to 10.
+
+        Example:
+
+        ```python
+        def get_weather(city: str) -> str:
+            return f"The weather in {city} is sunny."
+
+        react = dspy.ReAct(signature="question->answer", tools=[get_weather])
+        pred = react(question="What is the weather in Tokyo?")
+        ```
         """
         super().__init__()
         self.signature = signature = ensure_signature(signature)
diff --git a/dspy/utils/usage_tracker.py b/dspy/utils/usage_tracker.py
index 2643645a..5199f3ad 100644
--- a/dspy/utils/usage_tracker.py
+++ b/dspy/utils/usage_tracker.py
@@ -38,7 +38,7 @@ class UsageTracker:
         result = dict(usage_entry2)
         for k, v in usage_entry1.items():
             current_v = result.get(k)
-            if isinstance(v, dict):
+            if isinstance(v, dict) or isinstance(current_v, dict):
                 result[k] = self._merge_usage_entries(current_v, v)
             else:
                 result[k] = (current_v or 0) + (v or 0)


Test patch:
diff --git a/tests/adapters/test_chat_adapter.py b/tests/adapters/test_chat_adapter.py
index 3d8a67b7..969a8f17 100644
--- a/tests/adapters/test_chat_adapter.py
+++ b/tests/adapters/test_chat_adapter.py
@@ -244,6 +244,9 @@ def test_chat_adapter_formats_image_with_few_shot_examples():
     # 1 system message, 2 few shot examples (1 user and assistant message for each example), 1 user message
     assert len(messages) == 6
 
+    assert "[[ ## completed ## ]]\n" in messages[2]["content"]
+    assert "[[ ## completed ## ]]\n" in messages[4]["content"]
+
     assert {"type": "image_url", "image_url": {"url": "https://example.com/image1.jpg"}} in messages[1]["content"]
     assert {"type": "image_url", "image_url": {"url": "https://example.com/image2.jpg"}} in messages[3]["content"]
     assert {"type": "image_url", "image_url": {"url": "https://example.com/image3.jpg"}} in messages[5]["content"]
@@ -350,3 +353,26 @@ def test_chat_adapter_with_tool():
     # Tool arguments format should be included in the user message
     assert "{'city': {'type': 'string'}}" in messages[1]["content"]
     assert "{'country': {'type': 'string'}, 'year': {'type': 'integer'}}" in messages[1]["content"]
+
+
+def test_chat_adapter_formats_conversation_history():
+    class MySignature(dspy.Signature):
+        question: str = dspy.InputField()
+        history: dspy.History = dspy.InputField()
+        answer: str = dspy.OutputField()
+
+    history = dspy.History(
+        messages=[
+            {"question": "What is the capital of France?", "answer": "Paris"},
+            {"question": "What is the capital of Germany?", "answer": "Berlin"},
+        ]
+    )
+
+    adapter = dspy.ChatAdapter()
+    messages = adapter.format(MySignature, [], {"question": "What is the capital of France?", "history": history})
+
+    assert len(messages) == 6
+    assert messages[1]["content"] == "[[ ## question ## ]]\nWhat is the capital of France?"
+    assert messages[2]["content"] == "[[ ## answer ## ]]\nParis\n\n[[ ## completed ## ]]\n"
+    assert messages[3]["content"] == "[[ ## question ## ]]\nWhat is the capital of Germany?"
+    assert messages[4]["content"] == "[[ ## answer ## ]]\nBerlin\n\n[[ ## completed ## ]]\n"
diff --git a/tests/adapters/test_json_adapter.py b/tests/adapters/test_json_adapter.py
index cd561fe0..7db4a320 100644
--- a/tests/adapters/test_json_adapter.py
+++ b/tests/adapters/test_json_adapter.py
@@ -419,3 +419,26 @@ def test_json_adapter_with_tool():
             },
         },
     }
+
+
+def test_json_adapter_formats_conversation_history():
+    class MySignature(dspy.Signature):
+        question: str = dspy.InputField()
+        history: dspy.History = dspy.InputField()
+        answer: str = dspy.OutputField()
+
+    history = dspy.History(
+        messages=[
+            {"question": "What is the capital of France?", "answer": "Paris"},
+            {"question": "What is the capital of Germany?", "answer": "Berlin"},
+        ]
+    )
+
+    adapter = dspy.JSONAdapter()
+    messages = adapter.format(MySignature, [], {"question": "What is the capital of France?", "history": history})
+
+    assert len(messages) == 6
+    assert messages[1]["content"] == "[[ ## question ## ]]\nWhat is the capital of France?"
+    assert messages[2]["content"] == '{\n  "answer": "Paris"\n}'
+    assert messages[3]["content"] == "[[ ## question ## ]]\nWhat is the capital of Germany?"
+    assert messages[4]["content"] == '{\n  "answer": "Berlin"\n}'
diff --git a/tests/adapters/test_tool.py b/tests/adapters/test_tool.py
index de2f64d8..58938b87 100644
--- a/tests/adapters/test_tool.py
+++ b/tests/adapters/test_tool.py
@@ -5,6 +5,7 @@ import pytest
 from pydantic import BaseModel
 
 from dspy.adapters.types.tool import Tool
+import dspy
 
 
 # Test fixtures
@@ -363,3 +364,14 @@ async def test_async_concurrent_calls():
     # Check that it ran concurrently (should take ~0.1s, not ~0.5s)
     # We use 0.3s as threshold to account for some overhead
     assert end_time - start_time < 0.3
+
+
+def test_async_tool_call_in_sync_mode():
+    tool = Tool(async_dummy_function)
+    with dspy.context(allow_tool_async_sync_conversion=False):
+        with pytest.raises(ValueError):
+            result = tool(x=1, y="hello")
+
+    with dspy.context(allow_tool_async_sync_conversion=True):
+        result = tool(x=1, y="hello")
+        assert result == "hello 1"
diff --git a/tests/utils/test_usage_tracker.py b/tests/utils/test_usage_tracker.py
index 86b2d9ba..70244b32 100644
--- a/tests/utils/test_usage_tracker.py
+++ b/tests/utils/test_usage_tracker.py
@@ -170,3 +170,62 @@ def test_merge_usage_entries_with_new_keys():
 
     assert total_usage["model-x"]["prompt_tokens"] == 5
     assert total_usage["model-x"]["completion_tokens"] == 2
+
+
+def test_merge_usage_entries_with_none_values():
+    """Test tracking usage across multiple models."""
+    tracker = UsageTracker()
+
+    # Add usage entries for different models
+    usage_entries = [
+        {
+            "model": "gpt-4o-mini",
+            "usage": {
+                "prompt_tokens": 1117,
+                "completion_tokens": 46,
+                "total_tokens": 1163,
+                "prompt_tokens_details": None,
+                "completion_tokens_details": {},
+            },
+        },
+        {
+            "model": "gpt-4o-mini",
+            "usage": {
+                "prompt_tokens": 800,
+                "completion_tokens": 100,
+                "total_tokens": 900,
+                "prompt_tokens_details": {"cached_tokens": 50, "audio_tokens": 50},
+                "completion_tokens_details": None,
+            },
+        },
+        {
+            "model": "gpt-4o-mini",
+            "usage": {
+                "prompt_tokens": 800,
+                "completion_tokens": 100,
+                "total_tokens": 900,
+                "prompt_tokens_details": None,
+                "completion_tokens_details": {
+                    "reasoning_tokens": 1,
+                    "audio_tokens": 1,
+                    "accepted_prediction_tokens": 1,
+                    "rejected_prediction_tokens": 1,
+                },
+            },
+        },
+    ]
+
+    for entry in usage_entries:
+        tracker.add_usage(entry["model"], entry["usage"])
+
+    total_usage = tracker.get_total_tokens()
+
+    assert total_usage["gpt-4o-mini"]["prompt_tokens"] == 2717
+    assert total_usage["gpt-4o-mini"]["completion_tokens"] == 246
+    assert total_usage["gpt-4o-mini"]["total_tokens"] == 2963
+    assert total_usage["gpt-4o-mini"]["prompt_tokens_details"]["cached_tokens"] == 50
+    assert total_usage["gpt-4o-mini"]["prompt_tokens_details"]["audio_tokens"] == 50
+    assert total_usage["gpt-4o-mini"]["completion_tokens_details"]["reasoning_tokens"] == 1
+    assert total_usage["gpt-4o-mini"]["completion_tokens_details"]["audio_tokens"] == 1
+    assert total_usage["gpt-4o-mini"]["completion_tokens_details"]["accepted_prediction_tokens"] == 1
+    assert total_usage["gpt-4o-mini"]["completion_tokens_details"]["rejected_prediction_tokens"] == 1