llama-stack-mirror/llama_stack/apis/tools/tools.py
Ashwin Bharambe 2e544ecd8a feat(tools)!: substantial clean up of "Tool" related datatypes (#3627)
This is a sweeping change to clean up some gunk around our "Tool"
definitions.

First, we had two types `Tool` and `ToolDef`. The first of these was a
"Resource" type for the registry but we had stopped registering tools
inside the Registry long back (and only registered ToolGroups.) The
latter was for specifying tools for the Agents API. This PR removes the
former and adds an optional `toolgroup_id` field to the latter.

Secondly, as pointed out by @bbrowning in
https://github.com/llamastack/llama-stack/pull/3003#issuecomment-3245270132,
we were doing a lossy conversion from a full JSON schema from the MCP
tool specification into our ToolDefinition to send it to the model.
There is no necessity to do this -- we ourselves aren't doing any
execution at all but merely passing it to the chat completions API which
supports this. By doing this (and by doing it poorly), we encountered
limitations like not supporting array items, or not resolving $refs,
etc.

To fix this, we replaced the `parameters` field by `{ input_schema,
output_schema }` which can be full blown JSON schemas.

Finally, there were some types in our llama-related chat format
conversion which needed some cleanup. We are taking this opportunity to
clean those up.

This PR is a substantial breaking change to the API. However, given our
window for introducing breaking changes, this suits us just fine. I will
be landing a concurrent `llama-stack-client` change as well since API
shapes are changing.
2025-10-02 21:50:13 -07:00

221 lines
7 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.
from enum import Enum
from typing import Any, Literal, Protocol
from pydantic import BaseModel
from typing_extensions import runtime_checkable
from llama_stack.apis.common.content_types import URL, InterleavedContent
from llama_stack.apis.resource import Resource, ResourceType
from llama_stack.apis.version import LLAMA_STACK_API_V1
from llama_stack.providers.utils.telemetry.trace_protocol import trace_protocol
from llama_stack.schema_utils import json_schema_type, webmethod
from .rag_tool import RAGToolRuntime
@json_schema_type
class ToolDef(BaseModel):
"""Tool definition used in runtime contexts.
:param name: Name of the tool
:param description: (Optional) Human-readable description of what the tool does
:param input_schema: (Optional) JSON Schema for tool inputs (MCP inputSchema)
:param output_schema: (Optional) JSON Schema for tool outputs (MCP outputSchema)
:param metadata: (Optional) Additional metadata about the tool
:param toolgroup_id: (Optional) ID of the tool group this tool belongs to
"""
toolgroup_id: str | None = None
name: str
description: str | None = None
input_schema: dict[str, Any] | None = None
output_schema: dict[str, Any] | None = None
metadata: dict[str, Any] | None = None
@json_schema_type
class ToolGroupInput(BaseModel):
"""Input data for registering a tool group.
:param toolgroup_id: Unique identifier for the tool group
:param provider_id: ID of the provider that will handle this tool group
:param args: (Optional) Additional arguments to pass to the provider
:param mcp_endpoint: (Optional) Model Context Protocol endpoint for remote tools
"""
toolgroup_id: str
provider_id: str
args: dict[str, Any] | None = None
mcp_endpoint: URL | None = None
@json_schema_type
class ToolGroup(Resource):
"""A group of related tools managed together.
:param type: Type of resource, always 'tool_group'
:param mcp_endpoint: (Optional) Model Context Protocol endpoint for remote tools
:param args: (Optional) Additional arguments for the tool group
"""
type: Literal[ResourceType.tool_group] = ResourceType.tool_group
mcp_endpoint: URL | None = None
args: dict[str, Any] | None = None
@json_schema_type
class ToolInvocationResult(BaseModel):
"""Result of a tool invocation.
:param content: (Optional) The output content from the tool execution
:param error_message: (Optional) Error message if the tool execution failed
:param error_code: (Optional) Numeric error code if the tool execution failed
:param metadata: (Optional) Additional metadata about the tool execution
"""
content: InterleavedContent | None = None
error_message: str | None = None
error_code: int | None = None
metadata: dict[str, Any] | None = None
class ToolStore(Protocol):
async def get_tool(self, tool_name: str) -> ToolDef: ...
async def get_tool_group(self, toolgroup_id: str) -> ToolGroup: ...
class ListToolGroupsResponse(BaseModel):
"""Response containing a list of tool groups.
:param data: List of tool groups
"""
data: list[ToolGroup]
class ListToolDefsResponse(BaseModel):
"""Response containing a list of tool definitions.
:param data: List of tool definitions
"""
data: list[ToolDef]
@runtime_checkable
@trace_protocol
class ToolGroups(Protocol):
@webmethod(route="/toolgroups", method="POST", level=LLAMA_STACK_API_V1)
async def register_tool_group(
self,
toolgroup_id: str,
provider_id: str,
mcp_endpoint: URL | None = None,
args: dict[str, Any] | None = None,
) -> None:
"""Register a tool group.
:param toolgroup_id: The ID of the tool group to register.
:param provider_id: The ID of the provider to use for the tool group.
:param mcp_endpoint: The MCP endpoint to use for the tool group.
:param args: A dictionary of arguments to pass to the tool group.
"""
...
@webmethod(route="/toolgroups/{toolgroup_id:path}", method="GET", level=LLAMA_STACK_API_V1)
async def get_tool_group(
self,
toolgroup_id: str,
) -> ToolGroup:
"""Get a tool group by its ID.
:param toolgroup_id: The ID of the tool group to get.
:returns: A ToolGroup.
"""
...
@webmethod(route="/toolgroups", method="GET", level=LLAMA_STACK_API_V1)
async def list_tool_groups(self) -> ListToolGroupsResponse:
"""List tool groups with optional provider.
:returns: A ListToolGroupsResponse.
"""
...
@webmethod(route="/tools", method="GET", level=LLAMA_STACK_API_V1)
async def list_tools(self, toolgroup_id: str | None = None) -> ListToolDefsResponse:
"""List tools with optional tool group.
:param toolgroup_id: The ID of the tool group to list tools for.
:returns: A ListToolDefsResponse.
"""
...
@webmethod(route="/tools/{tool_name:path}", method="GET", level=LLAMA_STACK_API_V1)
async def get_tool(
self,
tool_name: str,
) -> ToolDef:
"""Get a tool by its name.
:param tool_name: The name of the tool to get.
:returns: A ToolDef.
"""
...
@webmethod(route="/toolgroups/{toolgroup_id:path}", method="DELETE", level=LLAMA_STACK_API_V1)
async def unregister_toolgroup(
self,
toolgroup_id: str,
) -> None:
"""Unregister a tool group.
:param toolgroup_id: The ID of the tool group to unregister.
"""
...
class SpecialToolGroup(Enum):
"""Special tool groups with predefined functionality.
:cvar rag_tool: Retrieval-Augmented Generation tool group for document search and retrieval
"""
rag_tool = "rag_tool"
@runtime_checkable
@trace_protocol
class ToolRuntime(Protocol):
tool_store: ToolStore | None = None
rag_tool: RAGToolRuntime | None = None
# TODO: This needs to be renamed once OPEN API generator name conflict issue is fixed.
@webmethod(route="/tool-runtime/list-tools", method="GET", level=LLAMA_STACK_API_V1)
async def list_runtime_tools(
self, tool_group_id: str | None = None, mcp_endpoint: URL | None = None
) -> ListToolDefsResponse:
"""List all tools in the runtime.
:param tool_group_id: The ID of the tool group to list tools for.
:param mcp_endpoint: The MCP endpoint to use for the tool group.
:returns: A ListToolDefsResponse.
"""
...
@webmethod(route="/tool-runtime/invoke", method="POST", level=LLAMA_STACK_API_V1)
async def invoke_tool(self, tool_name: str, kwargs: dict[str, Any]) -> ToolInvocationResult:
"""Run a tool with the given arguments.
:param tool_name: The name of the tool to invoke.
:param kwargs: A dictionary of arguments to pass to the tool.
:returns: A ToolInvocationResult.
"""
...