Python `helloworld` sample README expected output does not match `test_client.py`

[Om22210564]

The expected output documented in samples/python/agents/helloworld/README.md does not match the behavior of the current Python helloworld sample.

The README's Expected Output Snippet shows output for:

• displaying the public AgentCard
• a non-streaming call
• a streaming call
• an extended AgentCard
• task history and artifacts

However, running the documented command:

python test_client.py

currently starts an interactive session and only performs the non-streaming send_message() flow for each user input.

Starting an interactive session with A2A Server [http://127.0.0.1:9999]
Use `exit` to quit.
user > hi
Initializes the A2ACardResolver instance with an HTTP client

Successfully fetched the public agent card:

--- Public Agent Card - Non-Streaming Call ---

Initializing a non-streaming client.
Response:
task {
  id: "..."
  ...
  artifacts {
    parts {
      text: "Hello, World! I have received your request (hi)"
      media_type: "text/plain"
    }
  }
  ...
}

--
user >

In particular, the public AgentCard details are not displayed

Relevant Code

Also, in test_client.py already contains functions for the broader workflow:

async def show_agent_card():
    ...

async def send_message(...):
    ...

async def send_steaming_message(...):
    ...

async def show_extended_card():
    ...

def test_client_workflow(...):
    asyncio.run(show_agent_card())
    asyncio.run(send_message(text_query))
    asyncio.run(send_steaming_message(text_query))
    asyncio.run(show_extended_card())

However, the executable entry point currently calls main(), whose interactive loop only invokes send_message():

def main():
    ...
    while prompt and prompt != 'exit':
        asyncio.run(send_message(prompt))
        prompt = input('--\nuser > ')

The Expected snippet output appears to correspond more closely to samples/go/agents/helloworld/test_client.go demonstration

Expected Behaviour

Could we clarify which behavior is intended for python test_client.py?

1. update the README to document the current interactive send_message() behavior, or
2. update test_client.py so that the public AgentCard, streaming call, and extended AgentCard workflow described in the README is executed?

I'd be happy to contribute a fix in either direction once the intended behavior is clarified.

[CAOShurong]

Reproduced on a2aproject/a2a-samples origin/main at 6603ba3f2c31a7ef33e70b9d8b5b5f8be42ac9a3 (Python 3.13.1; a2a-sdk==1.1.0 from this sample's requirements.txt).

Following the README flow, I started __main__.py on port 9999 and ran:

python test_client.py
input: Say hello.
input: exit

The command exited 0 and produced the interactive prompt plus only:

--- Public Agent Card - Non-Streaming Call ---

The response contained the completed task/artifact, but there was no display_agent_card() output, no --- Public Agent Card - Streaming Call --- section, and no extended Agent Card output. The broader sequence exists in test_client_workflow() (lines 121–129), but the executable entry point calls main() (lines 132–142), which only invokes send_message().

So the mismatch is reproducible as described. The maintainer decision is still needed on which interface is authoritative: either make the documented workflow an explicit non-interactive command/test, or revise the README snippet to describe the current interactive behavior.