alibaba/spring-ai-alibaba · error · IllegalStateException

Failed to parse any valid result from streaming response

Error message

Failed to parse any valid result from streaming response

What it means

parseStreamingResponse iterates SSE/stream chunks from an A2A server trying to extract a valid result; if no chunk could be parsed into a usable result by the end of the stream, it throws this IllegalStateException. It means the remote agent streamed nothing parseable (or only heartbeat/unknown events).

Source

Thrown at spring-ai-alibaba-agent-framework/src/main/java/com/alibaba/cloud/ai/graph/agent/a2a/A2aNodeActionWithConfig.java:537

				try {
					Map<String, Object> parsed = JSON.parseObject(jsonContent,
							new TypeReference<Map<String, Object>>() {
							});
					Map<String, Object> result = (Map<String, Object>) parsed.get("result");
					if (result != null) {
						if (result.containsKey("artifact") || lastResult == null) {
							lastResult = result;
						}
					}
				}
				catch (Exception e) {
					continue;
				}
			}
		}

		if (lastResult == null) {
			throw new IllegalStateException("Failed to parse any valid result from streaming response");
		}
		Map<String, Object> resultMap = new HashMap<>();
		resultMap.put("result", lastResult);
		return resultMap;
	}

	private String extractResponseText(Map<String, Object> result) {
		if (result == null) {
			throw new IllegalStateException("Result is null, cannot extract response text");
		}

		if ("status-update".equals(result.get("kind"))) {
			Map<String, Object> status = (Map<String, Object>) result.get("status");
			if (status != null) {
				String state = (String) status.get("state");
				if ("completed".equals(state)) {
					return "";
				}

View on GitHub (pinned to f82da0b50f)

Solutions

1. Verify the remote A2A server is up and the AgentCard.url points to the JSON-RPC/stream endpoint, not a UI or docs page
2. Check server-side logs for the request; ensure the agent actually emits message/stream events (status-update/artifact-update)
3. Upgrade or align the A2A protocol version on both client and server so event shapes match what parseStreamingResponse expects
4. Wrap the call and retry or fall back to the non-streaming message/send endpoint

Example fix

// before
String url = "https://host/"; // UI root, not the A2A endpoint
// after
String url = agentCard.url(); // e.g. https://host/a2a/v1

// pre-check: ensure the endpoint answers before streaming
// e.g. fetch agent card: if (agentCard.url() == null || agentCard.url().isBlank()) fail fast;

try {
    Map<String,Object> result = action.autoDetectAndParseResponse(...);
} catch (IllegalStateException e) {
    // log stream contents/endpoint, retry once, then fall back to non-streaming message/send
}

When it happens

Trigger: Calling autoDetectAndParseResponse -> parseStreamingResponse against an A2A endpoint whose message/stream response yields no chunk matching the expected shapes (status-update, artifact-update, JSON-RPC result), or the stream closes immediately.

Common situations: Remote A2A server returns an error event or empty stream; server version speaks a different A2A protocol shape than the parser expects; network proxy truncates the SSE stream before any data event; wrong endpoint URL returning HTML error page.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• Failed to build JSON-RPC streaming payload
• AppTypeNotSupport
• Invalid memory parameter
• Invalid iterations parameter
• Invalid parallel parameter

AI-assisted analysis of alibaba/spring-ai-alibaba@f82da0b50f (2026-09-09). Data as JSON: /api/errors/ea528e687f9a0871. Report an issue: GitHub.