6. Interact with the server

6. Interact with the server

With the HelloWorld server running, you can interact with it using a client implementation (often provided by the SDK as an A2AClient).

The basic client workflow is:

1. Fetch the AgentCard from the server’s well-known endpoint.
2. Initialize a client with that AgentCard (and credentials if needed).
3. Send a non-streaming request (message/send) and inspect the response.
4. Send a streaming request (message/stream) and inspect streamed events.

Run the HelloWorld test client

In a2a-samples, there is a ready-made test client:

python samples/python/agents/helloworld/test_client.py

You should see JSON output for:

• a non-streaming response (usually a single message), and
• a streaming response (events over the stream).

Once you’ve confirmed both paths work, you’re ready to explore richer examples.