A2A agent card URL defaults to 0.0.0.0 and breaks Kubernetes inter-pod communication
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Tried to send an A2A message from Travel Agent to Weather Agent on EKS and got:
A2AClientHTTPError: HTTP Error 503: Network communication error
fetching agent card from http://0.0.0.0:9000/.well-known/agent-card.json:
All connection attempts failedThe A2A server binds to host=0.0.0.0 by default and publishes http://0.0.0.0:9000/ as the url in its agent card. The initial card fetch (using the a2a_agents.json URL) succeeds, but the LLM reads the url field from the card and passes it as target_agent_url to a2a_send_message, so it tries connecting to an unreachable 0.0.0.0 within the cluster.
Fix: set a2a.http_url to the Kubernetes Service FQDN in Helm values.
a2a:
http_url: "http://weather-agent.agents:9000/"This overwrites the card's url field, making it reachable from other pods in the cluster.
