{"record":{"id":"d653f76ff10305a6","repo":"deepseek-ai/deepseek-harness","slug":"browser-time-zone-is-unsupported-json-stringify","errorCode":null,"errorMessage":"browser time zone is unsupported: ${JSON.stringify(value)}","messagePattern":"browser time zone is unsupported: (.+?)","errorType":"validation","errorClass":"TypeError","httpStatus":null,"severity":"error","filePath":"packages/context/time-context/src/request-zone.ts","lineNumber":34,"sourceCode":"  const source = message.source\n  const value = source.kind === 'user'\n    && 'rpcId' in source\n    && typeof source.rpcId === 'string'\n    && 'clientTimeZone' in source\n    && typeof source.clientTimeZone === 'string'\n    ? source.clientTimeZone\n    : undefined\n  if (value === undefined) return undefined\n  if (value !== 'UTC' && !IANA_TIME_ZONE.test(value)) {\n    throw new TypeError(\n      `browser time zone must be canonical UTC or IANA Area/Location: ${JSON.stringify(value)}`,\n    )\n  }\n  let canonical: string\n  try {\n    canonical = new Intl.DateTimeFormat('en-US', { timeZone: value }).resolvedOptions().timeZone\n  } catch (error: unknown) {\n    throw new TypeError(`browser time zone is unsupported: ${JSON.stringify(value)}`, { cause: error })\n  }\n  if (canonical !== value) {\n    throw new TypeError(`browser time zone must be canonical: ${JSON.stringify(value)}`)\n  }\n  return value\n}\n\n/**\n * Derive the unique, mixed, or missing browser zone for one open turn.\n * @param messages - Entered and proposed user messages belonging to the turn.\n * @returns Sorted, duplicate-free browser-zone facts.\n * @throws TypeError when a user-rpc source carries an invalid or noncanonical zone.\n */\nexport function deriveBrowserTimeZoneContext(\n  messages: readonly UserMessage[],\n): BrowserTimeZoneContext {\n  const timeZones = [...new Set(messages.flatMap((message) => {\n    const timeZone = browserTimeZone(message)","sourceCodeStart":16,"sourceCodeEnd":52,"githubUrl":"https://github.com/deepseek-ai/deepseek-harness/blob/b150a551b8d465e31e418e1b2eaf5e79bbb7d28e/packages/context/time-context/src/request-zone.ts#L16-L52","documentation":"Error \"browser time zone is unsupported: ${JSON.stringify(value)}\" thrown in deepseek-ai/deepseek-harness.","triggerScenarios":"Thrown at packages/context/time-context/src/request-zone.ts:34 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Use a supported browser time zone value."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"b150a551b8d465e31e418e1b2eaf5e79bbb7d28e","analyzedAt":"2026-08-24T18:12:29.105Z","schemaVersion":2},"datasetVersion":"2026-08-24T22:17:12.610Z"}