Severity: medium / Confidence: high / Category: bug Triage: confirmed-bug Detected against: openclaw v2026.5.18 (latest stable at time of scan, 2026-05-18) Tooling: clawpatch 0.3.0 + acpx/claude-sonnet-4-5 via Brad Mills protocol

Evidence

• scripts/print-cli-backend-live-metadata.ts:17-29 (None)

process.stdout.write(
    JSON.stringify(
      {
        provider,
        unsupported: true,
        ...
      },
      null,
      2,
    ),
  );
  process.exit(0);

Reasoning

On the codex-cli early-exit path, process.stdout.write() is called immediately before process.exit(0). When stdout is a pipe (e.g. CI capturing output, jq, or other tooling), Node.js buffers writes and process.exit() bypasses the drain step, causing partial or empty output. This is a well-known Node.js hazard. The non-early-exit path at the bottom of the file avoids this because the process drains naturally after the top-level await settles, but the codex-cli branch does not.

Reproduction

node scripts/print-cli-backend-live-metadata.ts codex-cli | cat — may produce empty output on a slow pipe; consistently observed when the stdout buffer is larger than the write.

Recommendation

Either use process.stdout.write(data, () => process.exit(0)) to exit only after the drain callback fires, or set process.exitCode = 0 and remove the explicit process.exit(0) so the process drains normally. The latter matches the non-early-exit path at the bottom of the file.

Why existing tests miss this

No tests exist for this script and the truncation only manifests when stdout is a pipe with buffering, which a simple unit test would not exercise.

Suggested regression test

Shell test: node scripts/print-cli-backend-live-metadata.ts codex-cli | python3 -c "import sys, json; json.load(sys.stdin)" — must parse without error.

Minimum fix scope

Replace process.exit(0) with process.exitCode = 0 in the codex-cli branch of scripts/print-cli-backend-live-metadata.ts.

Standardized clawpatch finding. Persistent in v2026.5.18 (not resolved by upgrading from v2026.5.12). Finding ID: fnd_sig-feat-cli-command-23edfe2554-_eba7993d07.