[Bug]: Use the Agent Delegation mechanism in order to leverage other agents under AgentHub

[DLNovice]

Is there an existing issue for the same bug? (If one exists, thumbs up or comment on the issue instead).

• I have checked the existing issues.

Describe the bug and reproduction steps

Hello, friends!I’m currently trying to use the Agent Delegation mechanism in order to leverage other agents under AgentHub, such as browsing_agent or readonly_agent. However, all my attempts so far have failed.
I’m using OpenHands 0.53.0, and I’ve tried the following:

1. I attempted several conversations, but the default CodeActAgent never used the Delegation mechanism to delegate tasks to other agents. Even after I commented out the browser tool and fetch tool from CodeActAgent, it still wouldn’t delegate tasks to browsing_agent.
2. I also tried modifying the config.toml file to switch the default agent, for example:

[core]
default_agent = "BrowsingAgent"
# default_agent = "ReadOnlyAgent"

But after starting up, it was still using CodeActAgent by default.
3) I also tried using OpenHands 0.51.0 and other versions, but the Delegation mechanism still didn’t work.
4) I also tried using test code to test the Agent and Delegation mechanisms, for example:

poetry run python ./openhands/core/main.py \
        -i 10 \
        -t "Who is Karpathy?" \
        -c BrowsingAgent \
        -l llm

poetry run pytest tests/unit/controller/test_agent_delegation.py

But no errors were reported.

After checking the OpenHands issues, it seems that the recent versions of OpenHands no longer maintain the Agent Delegation mechanism? And it looks like the A2A protocol may still need some time before it goes live?
How can I currently use the Agent Delegation mechanism?Thanks!

OpenHands Installation

Docker command in README

OpenHands Version

0.53.0

Model Name

No response

Operating System

None

Logs, Errors, Screenshots, and Additional Context

No response