llama-stack-mirror/llama_stack/providers/remote/inference/vllm/vllm.py
Eric Huang 7027b537e0 feat: RFC: tools API rework
# What does this PR do?
This PR proposes updates to the tools API in Inference and Agent.

Goals:
1. Agent's tool specification should be consistent with Inference's tool spec, but with add-ons.
2. Formal types should be defined for built in tools. Currently Agent tools args are untyped, e.g. how does one know that `builtin::rag_tool` takes a `vector_db_ids` param or even how to know 'builtin::rag_tool' is even available (in code, outside of docs)?

Inference:
1. BuiltinTool is to be removed and replaced by a formal `type` parameter.
2. 'brave_search' is replaced by 'web_search' to be more generic. It will still be translated back to brave_search when the prompt is constructed to be consistent with model training.
3. I'm not sure what `photogen` is. Maybe it can be removed?

Agent:
1. Uses the same format as in Inference for builtin tools.
2. New tools types are added, i.e. knowledge_sesarch (currently rag_tool), and MCP tool.
3. Toolgroup as a concept will be removed since it's really only used for MCP.
4. Instead MCPTool is its own type and available tools provided by the server will be expanded by default. Users can specify a subset of tool names if desired.

Example snippet:
```

agent = Agent(
    client,
    model=model_id,
    instructions="You are a helpful assistant. Use the tools you have access to for providing relevant answers.",
    tools=[
        KnowledgeSearchTool(vector_store_id="1234"),
        KnowledgeSearchTool(vector_store_id="5678", name="paper_search", description="Search research papers"),
        KnowledgeSearchTool(vector_store_id="1357", name="wiki_search", description="Search wiki pages"),
        # no need to register toolgroup, just pass in the server uri
        # all available tools will be used
        MCPTool(server_uri="http://localhost:8000/sse"),
        # can specify a subset of available tools
        MCPTool(server_uri="http://localhost:8000/sse", tool_names=["list_directory"]),
        MCPTool(server_uri="http://localhost:8000/sse", tool_names=["list_directory"]),
        # custom tool
        my_custom_tool,
    ]
)
```

## Test Plan
# What does this PR do?


## Test Plan
# What does this PR do?


## Test Plan
2025-03-26 11:14:41 -07:00

406 lines
15 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import json
import logging
from typing import AsyncGenerator, List, Optional, Union
import httpx
from openai import AsyncOpenAI
from openai.types.chat.chat_completion_chunk import (
ChatCompletionChunk as OpenAIChatCompletionChunk,
)
from llama_stack.apis.common.content_types import (
InterleavedContent,
InterleavedContentItem,
TextDelta,
ToolCallDelta,
ToolCallParseStatus,
)
from llama_stack.apis.inference import (
ChatCompletionRequest,
ChatCompletionResponse,
ChatCompletionResponseEvent,
ChatCompletionResponseEventType,
ChatCompletionResponseStreamChunk,
CompletionMessage,
CompletionRequest,
CompletionResponse,
CompletionResponseStreamChunk,
EmbeddingsResponse,
EmbeddingTaskType,
Inference,
LogProbConfig,
Message,
ResponseFormat,
ResponseFormatType,
SamplingParams,
TextTruncation,
ToolChoice,
ToolConfig,
ToolDefinition,
ToolPromptFormat,
)
from llama_stack.apis.models import Model, ModelType
from llama_stack.models.llama.datatypes import StopReason, ToolCall
from llama_stack.models.llama.sku_list import all_registered_models
from llama_stack.providers.datatypes import ModelsProtocolPrivate
from llama_stack.providers.utils.inference.model_registry import (
ModelRegistryHelper,
build_hf_repo_model_entry,
)
from llama_stack.providers.utils.inference.openai_compat import (
UnparseableToolCall,
convert_message_to_openai_dict,
convert_tool_call,
get_sampling_options,
process_chat_completion_stream_response,
process_completion_response,
process_completion_stream_response,
)
from llama_stack.providers.utils.inference.prompt_adapter import (
completion_request_to_prompt,
content_has_media,
interleaved_content_as_str,
request_has_media,
)
from .config import VLLMInferenceAdapterConfig
log = logging.getLogger(__name__)
def build_hf_repo_model_entries():
return [
build_hf_repo_model_entry(
model.huggingface_repo,
model.descriptor(),
)
for model in all_registered_models()
if model.huggingface_repo
]
def _convert_to_vllm_tool_calls_in_response(
tool_calls,
) -> List[ToolCall]:
if not tool_calls:
return []
return [
ToolCall(
call_id=call.id,
tool_name=call.function.name,
arguments=json.loads(call.function.arguments),
arguments_json=call.function.arguments,
)
for call in tool_calls
]
def _convert_to_vllm_tools_in_request(tools: List[ToolDefinition]) -> List[dict]:
if tools is None:
return tools
compat_tools = []
for tool in tools:
properties = {}
compat_required = []
tool_name = tool.name
if tool.parameters:
for tool_key, tool_param in tool.parameters.items():
properties[tool_key] = {"type": tool_param.param_type}
if tool_param.description:
properties[tool_key]["description"] = tool_param.description
if tool_param.default:
properties[tool_key]["default"] = tool_param.default
if tool_param.required:
compat_required.append(tool_key)
compat_tool = {
"type": "function",
"function": {
"name": tool_name,
"description": tool.description,
"parameters": {
"type": "object",
"properties": properties,
"required": compat_required,
},
},
}
compat_tools.append(compat_tool)
if len(compat_tools) > 0:
return compat_tools
return None
def _convert_to_vllm_finish_reason(finish_reason: str) -> StopReason:
return {
"stop": StopReason.end_of_turn,
"length": StopReason.out_of_tokens,
"tool_calls": StopReason.end_of_message,
}.get(finish_reason, StopReason.end_of_turn)
async def _process_vllm_chat_completion_stream_response(
stream: AsyncGenerator[OpenAIChatCompletionChunk, None],
) -> AsyncGenerator:
event_type = ChatCompletionResponseEventType.start
tool_call_buf = UnparseableToolCall()
async for chunk in stream:
if not chunk.choices:
log.warning("vLLM failed to generation any completions - check the vLLM server logs for an error.")
continue
choice = chunk.choices[0]
if choice.finish_reason:
args_str = tool_call_buf.arguments
args = None
try:
args = {} if not args_str else json.loads(args_str)
except Exception as e:
log.warning(f"Failed to parse tool call buffer arguments: {args_str} \nError: {e}")
if args:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=ToolCallDelta(
tool_call=ToolCall(
call_id=tool_call_buf.call_id,
tool_name=tool_call_buf.tool_name,
arguments=args,
arguments_json=args_str,
),
parse_status=ToolCallParseStatus.succeeded,
),
)
)
elif args_str:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.progress,
delta=ToolCallDelta(
tool_call=str(tool_call_buf),
parse_status=ToolCallParseStatus.failed,
),
)
)
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=ChatCompletionResponseEventType.complete,
delta=TextDelta(text=choice.delta.content or ""),
logprobs=None,
stop_reason=_convert_to_vllm_finish_reason(choice.finish_reason),
)
)
elif choice.delta.tool_calls:
tool_call = convert_tool_call(choice.delta.tool_calls[0])
tool_call_buf.tool_name += tool_call.tool_name
tool_call_buf.call_id += tool_call.call_id
tool_call_buf.arguments += tool_call.arguments
else:
yield ChatCompletionResponseStreamChunk(
event=ChatCompletionResponseEvent(
event_type=event_type,
delta=TextDelta(text=choice.delta.content or ""),
logprobs=None,
)
)
event_type = ChatCompletionResponseEventType.progress
class VLLMInferenceAdapter(Inference, ModelsProtocolPrivate):
def __init__(self, config: VLLMInferenceAdapterConfig) -> None:
self.register_helper = ModelRegistryHelper(build_hf_repo_model_entries())
self.config = config
self.client = None
async def initialize(self) -> None:
log.info(f"Initializing VLLM client with base_url={self.config.url}")
self.client = AsyncOpenAI(
base_url=self.config.url,
api_key=self.config.api_token,
http_client=None if self.config.tls_verify else httpx.AsyncClient(verify=False),
)
async def shutdown(self) -> None:
pass
async def unregister_model(self, model_id: str) -> None:
pass
async def completion(
self,
model_id: str,
content: InterleavedContent,
sampling_params: Optional[SamplingParams] = None,
response_format: Optional[ResponseFormat] = None,
stream: Optional[bool] = False,
logprobs: Optional[LogProbConfig] = None,
) -> Union[CompletionResponse, CompletionResponseStreamChunk]:
if sampling_params is None:
sampling_params = SamplingParams()
model = await self.model_store.get_model(model_id)
request = CompletionRequest(
model=model.provider_resource_id,
content=content,
sampling_params=sampling_params,
response_format=response_format,
stream=stream,
logprobs=logprobs,
)
if stream:
return self._stream_completion(request)
else:
return await self._nonstream_completion(request)
async def chat_completion(
self,
model_id: str,
messages: List[Message],
sampling_params: Optional[SamplingParams] = None,
response_format: Optional[ResponseFormat] = None,
tools: Optional[List[ToolDefinition]] = None,
tool_choice: Optional[ToolChoice] = ToolChoice.auto,
tool_prompt_format: Optional[ToolPromptFormat] = None,
stream: Optional[bool] = False,
logprobs: Optional[LogProbConfig] = None,
tool_config: Optional[ToolConfig] = None,
) -> AsyncGenerator:
if sampling_params is None:
sampling_params = SamplingParams()
model = await self.model_store.get_model(model_id)
# This is to be consistent with OpenAI API and support vLLM <= v0.6.3
# References:
# * https://platform.openai.com/docs/api-reference/chat/create#chat-create-tool_choice
# * https://github.com/vllm-project/vllm/pull/10000
if not tools and tool_config is not None:
tool_config.tool_choice = ToolChoice.none
request = ChatCompletionRequest(
model=model.provider_resource_id,
messages=messages,
sampling_params=sampling_params,
tools=tools or [],
stream=stream,
logprobs=logprobs,
response_format=response_format,
tool_config=tool_config,
)
if stream:
return self._stream_chat_completion(request, self.client)
else:
return await self._nonstream_chat_completion(request, self.client)
async def _nonstream_chat_completion(
self, request: ChatCompletionRequest, client: AsyncOpenAI
) -> ChatCompletionResponse:
params = await self._get_params(request)
r = await client.chat.completions.create(**params)
choice = r.choices[0]
result = ChatCompletionResponse(
completion_message=CompletionMessage(
content=choice.message.content or "",
stop_reason=_convert_to_vllm_finish_reason(choice.finish_reason),
tool_calls=_convert_to_vllm_tool_calls_in_response(choice.message.tool_calls),
),
logprobs=None,
)
return result
async def _stream_chat_completion(self, request: ChatCompletionRequest, client: AsyncOpenAI) -> AsyncGenerator:
params = await self._get_params(request)
stream = await client.chat.completions.create(**params)
if len(request.tools) > 0:
res = _process_vllm_chat_completion_stream_response(stream)
else:
res = process_chat_completion_stream_response(stream, request)
async for chunk in res:
yield chunk
async def _nonstream_completion(self, request: CompletionRequest) -> CompletionResponse:
params = await self._get_params(request)
r = await self.client.completions.create(**params)
return process_completion_response(r)
async def _stream_completion(self, request: CompletionRequest) -> AsyncGenerator:
params = await self._get_params(request)
stream = await self.client.completions.create(**params)
async for chunk in process_completion_stream_response(stream):
yield chunk
async def register_model(self, model: Model) -> Model:
model = await self.register_helper.register_model(model)
res = await self.client.models.list()
available_models = [m.id async for m in res]
if model.provider_resource_id not in available_models:
raise ValueError(
f"Model {model.provider_resource_id} is not being served by vLLM. "
f"Available models: {', '.join(available_models)}"
)
return model
async def _get_params(self, request: Union[ChatCompletionRequest, CompletionRequest]) -> dict:
options = get_sampling_options(request.sampling_params)
if "max_tokens" not in options:
options["max_tokens"] = self.config.max_tokens
input_dict = {}
if isinstance(request, ChatCompletionRequest) and request.tools is not None:
input_dict = {"tools": _convert_to_vllm_tools_in_request(request.tools)}
if isinstance(request, ChatCompletionRequest):
input_dict["messages"] = [await convert_message_to_openai_dict(m, download=True) for m in request.messages]
else:
assert not request_has_media(request), "vLLM does not support media for Completion requests"
input_dict["prompt"] = await completion_request_to_prompt(request)
if fmt := request.response_format:
if fmt.type == ResponseFormatType.json_schema.value:
input_dict["extra_body"] = {"guided_json": request.response_format.json_schema}
elif fmt.type == ResponseFormatType.grammar.value:
raise NotImplementedError("Grammar response format not supported yet")
else:
raise ValueError(f"Unknown response format {fmt.type}")
if request.logprobs and request.logprobs.top_k:
input_dict["logprobs"] = request.logprobs.top_k
return {
"model": request.model,
**input_dict,
"stream": request.stream,
**options,
}
async def embeddings(
self,
model_id: str,
contents: List[str] | List[InterleavedContentItem],
text_truncation: Optional[TextTruncation] = TextTruncation.none,
output_dimension: Optional[int] = None,
task_type: Optional[EmbeddingTaskType] = None,
) -> EmbeddingsResponse:
model = await self.model_store.get_model(model_id)
kwargs = {}
assert model.model_type == ModelType.embedding
assert model.metadata.get("embedding_dimension")
kwargs["dimensions"] = model.metadata.get("embedding_dimension")
assert all(not content_has_media(content) for content in contents), "VLLM does not support media for embeddings"
response = await self.client.embeddings.create(
model=model.provider_resource_id,
input=[interleaved_content_as_str(content) for content in contents],
**kwargs,
)
embeddings = [data.embedding for data in response.data]
return EmbeddingsResponse(embeddings=embeddings)