BerriAI/litellm · error · RuntimeError

A2A send_message failed: no response received after retry at

Error message

A2A send_message failed: no response received after retry attempts.

What it means

Error "A2A send_message failed: no response received after retry attempts." thrown in BerriAI/litellm.

Source

Thrown at litellm/a2a_protocol/main.py:311

                is_streaming=False,
            )
            card_url = get_agent_card_url(agent_card) if agent_card else None
        except Exception as e:
            try:
                map_a2a_exception(e, card_url, api_base, model=agent_name)
            except A2ALocalhostURLError as localhost_err:
                a2a_client = await handle_a2a_localhost_retry(
                    error=localhost_err,
                    agent_card=agent_card,
                    a2a_client=a2a_client,
                    is_streaming=False,
                )
                card_url = get_agent_card_url(agent_card) if agent_card else None
                continue
            except Exception:
                raise
    if a2a_response is None:
        raise RuntimeError("A2A send_message failed: no response received after retry attempts.")
    return a2a_response


async def _stream_messages(
    a2a_client: "A2AClientType", request: "SendStreamingMessageRequest"
) -> AsyncIterator["SendStreamingMessageResponse"]:
    """Stream message events via a2a-sdk 1.x and yield JSON-RPC chunks."""
    if _a2a_conversions is None:
        raise ImportError(
            "The 'a2a' package is required for A2A agent invocation. Install it with: pip install a2a-sdk"
        )

    pb_request: Final[CoreSendMessageRequest] = _a2a_conversions.to_core_send_message_request(request)
    async for event in a2a_client.send_message(pb_request, context=_get_a2a_call_context(a2a_client)):
        compat_chunk = _to_compat_stream_response(event, request_id=request.id)
        yield SendStreamingMessageResponse(root=compat_chunk)

View on GitHub (pinned to 6c2dcb801b)

Solutions

1. The agent did not respond after retries; check agent availability, URL, and increase timeout/retries if needed.

When it happens

Trigger: Thrown at litellm/a2a_protocol/main.py:311 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/3393829dfb8150e7. Report an issue: GitHub.