paperclipai/paperclip · error

CreateOS process exit status is missing.

Error message

CreateOS process exit status is missing.

What it means

The process stream delivered an `exit` event that contained neither a valid integer `exit_code` nor a `signal` string matching /^SIG[A-Z0-9]+$/. Without one of these the completion status is unknowable, so the plugin refuses to fabricate a result.

Solutions

1. Capture the raw exit frame and diff it against the documented exit-event schema.
2. Pin the CreateOS service version to one matching the plugin's expected protocol.
3. Check for intermediaries rewriting or filtering event fields.
4. Re-run the command; note cleanup will terminate the unfinished process tree, so a rerun is safe.

Example fix

// before
{ "type": "exit", "status": "done" }
// after
{ "type": "exit", "exit_code": 0 }   // or { "type": "exit", "signal": "SIGKILL" }

function hasExitStatus(e: Record<string, unknown>): boolean {
  const code = e.exit_code, sig = e.signal;
  return (typeof code === "number" && Number.isInteger(code))
    || (typeof sig === "string" && /^SIG[A-Z0-9]+$/.test(sig));
}

try { const r = await execute(client, params, signal); }
catch (e) {
  if (e instanceof Error && e.message === "CreateOS process exit status is missing.") {
    // exit frame malformed: re-run; cleanup has already terminated the tree
  } else throw e;
}

When it happens

Trigger: CreateOS emits {"type":"exit"} with missing/null exit_code and signal, a float exit_code, or a malformed signal name; a protocol change renames these fields.

Common situations: CreateOS version upgrade renaming exit fields; server crash while finalizing process exit; proxy stripping unknown fields from event JSON.

Understand the failure class

Background: "invalid response format", "malformed payload", "missing data field": when an API returns 200 but the response shape is wrong — this error's family across 23 libraries.

Related errors

• CreateOS process output has a sequence gap.
• CreateOS process output is invalid.
• CreateOS process sequence is invalid.
• CreateOS returned an invalid process frame.
• Photon attachment header is missing

AI-assisted analysis of paperclipai/paperclip@3f1d897a7c (2026-09-18). Data as JSON: /api/errors/c8e3c10ab10fb1be. Report an issue: GitHub.

Appendix: source

Thrown at packages/plugins/sandbox-providers/createos/src/execute.ts:169

          if (event.type === "heartbeat") continue;
          if (event.type === "data") {
            const seq = event.seq;
            if (typeof seq !== "number" || !Number.isSafeInteger(seq) || seq < 1) throw new Error("CreateOS process sequence is invalid.");
            if (seq <= cursor) continue;
            if (seq !== cursor + 1) throw new Error("CreateOS process output has a sequence gap.");
            if ((event.stream !== "stdout" && event.stream !== "stderr") ||
                typeof event.data_base64 !== "string" ||
                !/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/.test(event.data_base64)) {
              throw new Error("CreateOS process output is invalid.");
            }
            output.write(event.stream, Buffer.from(event.data_base64, "base64"));
            cursor = seq;
          } else if (event.type === "exit") {
            const exitCode = event.exit_code;
            const exitSignal = event.signal;
            if (!(typeof exitCode === "number" && Number.isInteger(exitCode)) &&
                !(typeof exitSignal === "string" && /^SIG[A-Z0-9]+$/.test(exitSignal))) {
              throw new Error("CreateOS process exit status is missing.");
            }
            completed = true;
            output.finish();
            return {
              exitCode: typeof exitCode === "number" ? exitCode : null,
              signal: typeof exitSignal === "string" ? exitSignal : null,
              timedOut: false, stdout: output.stdout, stderr: output.stderr,
              metadata: { processId, outputTruncated: output.truncated },
            };
          } else if (event.type === "error") {
            throw new Error(event.error === "output_offset_expired"
              ? "CreateOS process output was evicted before it could be read."
              : "CreateOS process stream reported an error.");
          } else {
            throw new Error("CreateOS returned an unknown process event.");
          }
        }
      } catch (error) {

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