smolagents

Use HuggingFace smolagents tools inside a Mellea session.

MelleaTool.from_smolagents() wraps any smolagents Tool instance so it can be passed to any MelleaSession call. The HuggingFace ecosystem provides many pre-built tools — PythonInterpreterTool, DuckDuckGoSearchTool, WikipediaSearchTool, and others.

Prerequisites: pip install 'mellea[smolagents]'

Using smolagents tools

# Requires: mellea[smolagents], mellea[ollama]
# Returns: ModelOutputThunk
from mellea import start_session
from mellea.backends import ModelOption
from mellea.backends.tools import MelleaTool

from smolagents import PythonInterpreterTool

# Wrap the smolagents tool
python_tool = MelleaTool.from_smolagents(PythonInterpreterTool())

m = start_session()
result = m.instruct(
    "Calculate the sum of numbers from 1 to 10 using Python",
    model_options={ModelOption.TOOLS: [python_tool]},
    tool_calls=True,
)

print(result)

if result.tool_calls:
    try:
        calc_result = result.tool_calls[python_tool.name].call_func()
        print(f"Calculation result: {calc_result}")
    except Exception as e:
        print(f"Tool execution failed: {e}")

from_smolagents() uses smolagents’ own JSON schema conversion, so the tool’s description and parameter types are preserved exactly.

Backend note: Tool calling requires a backend and model that support function calling (e.g., Ollama with granite4.1:3b, OpenAI with gpt-4o). The default Ollama setup supports this.

Full example: docs/examples/tools/smolagents_example.py

Which approach to use

Scenario	Use
Your tool exists as a LangChain BaseTool	MelleaTool.from_langchain(tool)
Your tool exists as a smolagents Tool	MelleaTool.from_smolagents(tool)
You have a plain Python function to expose	@tool decorator
You have LangChain message history to continue	convert_to_openai_messages → ChatContext
You want Mellea as an OpenAI endpoint for another framework	m serve

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See also: Tools and Agents | Context and Sessions