alibaba/spring-ai-alibaba · warning

Command timed out, restarting session

Error message

Command timed out, restarting session

What it means

collectOutput waited until the command deadline expired without the shell producing a final output line; it logs this warning, calls restart() to recreate the session, and returns with a timeout indication. The command is not allowed to run past the configured timeout.

Solutions

1. Increase the command timeout in the shell tool configuration if the workload legitimately needs longer.
2. Fix the command: add its own timeout (e.g. 'timeout 60 <cmd>'), redirect stdin from /dev/null for non-interactive use.
3. Split long work into smaller commands the agent can run sequentially.
4. Note the session was restarted; re-run any stateful setup (cd, exports) that the restart discarded.

Example fix

// before
shell.execute("npm install");
// after
shell.execute("timeout 600 npm install"); // plus raise configured timeout

if (result.timedOut()) { log.warn("Command {} timed out; session restarted", cmd); /* re-init session state and retry with longer timeout */ }

When it happens

Trigger: Running a long-running or blocking command (infinite loop, waiting on stdin, network hang) through execute so that no output line arrives before the deadline in outputQueue.poll.

Common situations: Agent asks the shell to run 'sleep 1000', an interactive command that blocks on input, or a command stuck on a network call exceeding the session's timeout setting.

Understand the failure class

Background: Request timed out: what client-side request timeouts mean across libraries (Request timed out, TIMED_OUT, APITimeoutError) — this error's family across 39 libraries.

• Timeouts: ETIMEDOUT, deadlines, and hung requests — what actually expires when a request times out.

Related errors

• Startup command failed:
• Failed to execute command
• Failed to initialize shell session
• Failed to restart shell session
• Shell session is not running

AI-assisted analysis of alibaba/spring-ai-alibaba@f82da0b50f (2026-09-09). Data as JSON: /api/errors/d2e8bb624272c654. Report an issue: GitHub.

Appendix: source

Thrown at spring-ai-alibaba-agent-framework/src/main/java/com/alibaba/cloud/ai/graph/agent/tools/ShellSessionManager.java:529

			} catch (IOException e) {
				throw new RuntimeException("Failed to execute command", e);
			}
		}

		private CommandResult collectOutput(String marker, long deadline, int maxOutputLines, Long maxOutputBytes) {
			List<String> lines = new ArrayList<>();
			int totalLines = 0;
			long totalBytes = 0;
			boolean truncatedByLines = false;
			boolean truncatedByBytes = false;
			Integer exitCode = null;
			boolean timedOut = false;

			while (true) {
				long remaining = deadline - System.currentTimeMillis();
				if (remaining <= 0) {
					timedOut = true;
					log.warn("Command timed out, restarting session");
					restart();
					break;
				}

				try {
					OutputLine outputLine = outputQueue.poll(remaining, TimeUnit.MILLISECONDS);
					if (outputLine == null) {
						timedOut = true;
						restart();
						break;
					}

					// Skip EOF markers
					if (outputLine.content == null) {
						continue;
					}

					String line = outputLine.content;

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