Artifact rendering?

I have code like this

```
from google.adk.agents import LlmAgent
from google.adk.tools import FunctionTool, ToolContext
from google.genai import types
from google.adk.artifacts import InMemoryArtifactService
from google.adk.sessions import InMemorySessionService

solver = LlmAgent(
name="solver_agent",
model="gemini-2.5-pro-preview-06-05",
description="Solve questions ",
instruction="Solve the problem, save it to an artifact",
output_key="question_solution.md"
)
```
here my problem is : my artifact is a result from the agent, not a function tool.
the result does show up in 'state' but not 'artifact' in the web UI.
i think if i use the adk-web, i should not be manually managing the session and artifact? or should I?
https://google.github.io/adk-docs/artifacts/ shows how to do it in the runner.
thanks.