{"record":{"id":"1e6659a3cd362c89","repo":"Egonex-AI/Understand-Anything","slug":"output-file-missing-after-write-outputpath-1e6659","errorCode":null,"errorMessage":"output file missing after write: ${outputPath}","messagePattern":"output file missing after write: (.+?)","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"understand-anything-plugin/skills/understand/extract-structure.mjs","lineNumber":138,"sourceCode":"\n    // Build result object\n    const result = buildExtractResult(file, totalLines, nonEmptyLines, analysis, callGraph, batchImportData);\n    results.push(result);\n  }\n\n  // Write output\n  const output = {\n    scriptCompleted: true,\n    filesAnalyzed: results.length,\n    filesSkipped,\n    analysisOutcomes,\n    results,\n  };\n\n  writeFileSync(outputPath, JSON.stringify(output, null, 2), 'utf-8');\n\n  if (!existsSync(outputPath)) {\n    throw new Error(`output file missing after write: ${outputPath}`);\n  }\n}\n\n// ---------------------------------------------------------------------------\n// Run only when executed directly as a CLI; importing the module (e.g. from\n// tests) must not trigger main().\n//\n// Canonicalize both sides through realpathSync. Node ESM resolves\n// import.meta.url through symlinks but pathToFileURL(process.argv[1]) preserves\n// them, so a raw equality check silently no-ops when the script is invoked via\n// a symlinked plugin install path (the default in Claude Code / Copilot CLI\n// caches). See GitHub issue #162.\n// ---------------------------------------------------------------------------\nfunction isCliEntry() {\n  if (!process.argv[1]) return false;\n  try {\n    const modulePath = realpathSync(fileURLToPath(import.meta.url));\n    const argvPath = realpathSync(process.argv[1]);","sourceCodeStart":120,"sourceCodeEnd":156,"githubUrl":"https://github.com/Egonex-AI/Understand-Anything/blob/32944829e7a63a9fa9c55d811d7f98a9530c6a6a/understand-anything-plugin/skills/understand/extract-structure.mjs#L120-L156","documentation":"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.","triggerScenarios":"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.","commonSituations":"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.","solutions":["Point outputPath at a local writable directory (not a network mount).","Check free space and inodes on the target volume.","Retry; if it reproduces, log fs.statSync error and realpathSync(dirname) to localize.","Use a tmpfs/local scratch dir for outputPath."],"exampleFix":null,"handlingStrategy":"retry","validationCode":"import { writeFileSync, existsSync } from 'node:fs';\nfunction safeWriteJson(path, value) {\n  writeFileSync(path, JSON.stringify(value, null, 2), 'utf-8');\n  if (!existsSync(path)) {\n    throw new Error(`write invisible at ${path}; check mount/space/quota`);\n  }\n}","typeGuard":null,"tryCatchPattern":"async function writeWithRetry(path, value, attempts = 3) {\n  for (let i = 0; i < attempts; i++) {\n    try {\n      writeFileSync(path, JSON.stringify(value, null, 2), 'utf-8');\n      if (existsSync(path)) return;\n    } catch {}\n    await new Promise((r) => setTimeout(r, 100 * (i + 1)));\n  }\n  throw new Error(`output file missing after write: ${path}`);\n}","preventionTips":["Write outputPath to a local filesystem, not a cached network mount.","Check free space and inodes before running.","In sandboxed runtimes, use a tmpfs/scratch path."],"tags":["skill","extract-structure","filesystem","write-verification","sandbox"],"backgroundTag":null,"analyzedSha":"32944829e7a63a9fa9c55d811d7f98a9530c6a6a","analyzedAt":"2026-08-12T10:25:44.261Z","schemaVersion":2},"datasetVersion":"2026-08-12T18:17:37.767Z"}