Egonex-AI/Understand-Anything · error · Error

output file missing after write: ${outputPath}

Error message

output file missing after write: ${outputPath}

What it means

Thrown by extract-structure.mjs right after writeFileSync(outputPath, ...) followed by existsSync(outputPath). Same defensive pattern as error 34: the write returned successfully but the file is not visible to a follow-up stat, guarding against filesystems with deferred visibility.

Source

Thrown at understand-anything-plugin/skills/understand/extract-structure.mjs:138

    // Build result object
    const result = buildExtractResult(file, totalLines, nonEmptyLines, analysis, callGraph, batchImportData);
    results.push(result);
  }

  // Write output
  const output = {
    scriptCompleted: true,
    filesAnalyzed: results.length,
    filesSkipped,
    analysisOutcomes,
    results,
  };

  writeFileSync(outputPath, JSON.stringify(output, null, 2), 'utf-8');

  if (!existsSync(outputPath)) {
    throw new Error(`output file missing after write: ${outputPath}`);
  }
}

// ---------------------------------------------------------------------------
// Run only when executed directly as a CLI; importing the module (e.g. from
// tests) must not trigger main().
//
// Canonicalize both sides through realpathSync. Node ESM resolves
// import.meta.url through symlinks but pathToFileURL(process.argv[1]) preserves
// them, so a raw equality check silently no-ops when the script is invoked via
// a symlinked plugin install path (the default in Claude Code / Copilot CLI
// caches). See GitHub issue #162.
// ---------------------------------------------------------------------------
function isCliEntry() {
  if (!process.argv[1]) return false;
  try {
    const modulePath = realpathSync(fileURLToPath(import.meta.url));
    const argvPath = realpathSync(process.argv[1]);

View on GitHub (pinned to 32944829e7)

Solutions

1. Point outputPath at a local writable directory (not a network mount).
2. Check free space and inodes on the target volume.
3. Retry; if it reproduces, log fs.statSync error and realpathSync(dirname) to localize.
4. Use a tmpfs/local scratch dir for outputPath.

import { writeFileSync, existsSync } from 'node:fs';
function safeWriteJson(path, value) {
  writeFileSync(path, JSON.stringify(value, null, 2), 'utf-8');
  if (!existsSync(path)) {
    throw new Error(`write invisible at ${path}; check mount/space/quota`);
  }
}

async function writeWithRetry(path, value, attempts = 3) {
  for (let i = 0; i < attempts; i++) {
    try {
      writeFileSync(path, JSON.stringify(value, null, 2), 'utf-8');
      if (existsSync(path)) return;
    } catch {}
    await new Promise((r) => setTimeout(r, 100 * (i + 1)));
  }
  throw new Error(`output file missing after write: ${path}`);
}

When it happens

Trigger: writeFileSync completes without error but existsSync(outputPath) returns false. Reproducible on network/overlay/fuse mounts with metadata caching, in sandboxed runtimes that intercept fs, or under quota/exhausted-inode conditions on certain drivers.

Common situations: Agent sandbox runtime intercepting writes. outputPath on an NFS/share with caching. Disk-full or inode-quota between write and stat. Mount-boundary path. Concurrent cleanup racing the stat.

Related errors

• output file missing after write: ${outputPath}
• output file missing after write: ${outputPath}
• Invalid input: must contain projectRoot and batchFiles array
• Unable to remove temporary benchmark artifacts
• Repository path does not exist: ${repoValue}

AI-assisted analysis of Egonex-AI/Understand-Anything@32944829e7 (2026-08-12). Data as JSON: /api/errors/1e6659a3cd362c89. Report an issue: GitHub.