{"record":{"id":"66eec2d632c821ce","repo":"davila7/claude-code-templates","slug":"invalid-response-from-x0-at-uploadurl-stderr","errorCode":null,"errorMessage":"Invalid response from x0.at: ${uploadUrl || stderr}","messagePattern":"Invalid response from x0\\.at: (.+?)","errorType":"exception","errorClass":"Error","httpStatus":null,"severity":"error","filePath":"cli-tool/src/session-sharing.js","lineNumber":241,"sourceCode":"      await fs.writeFile(tmpFile, JSON.stringify(sessionData, null, 2), 'utf8');\n\n      console.log(chalk.gray(`📁 Created temp file: ${tmpFile}`));\n      console.log(chalk.gray(`📤 Uploading to x0.at...`));\n\n      // Upload to x0.at using curl with form data\n      // x0.at API: curl -F'file=@yourfile.png' https://x0.at\n      // Response: Direct URL in plain text\n      const { stdout, stderr } = await execAsync(\n        `curl -s -F \"file=@${tmpFile}\" ${this.uploadUrl}`,\n        { maxBuffer: 10 * 1024 * 1024 } // 10MB buffer\n      );\n\n      // x0.at returns URL directly in plain text\n      const uploadUrl = stdout.trim();\n\n      // Validate response\n      if (!uploadUrl || !uploadUrl.startsWith('http')) {\n        throw new Error(`Invalid response from x0.at: ${uploadUrl || stderr}`);\n      }\n\n      console.log(chalk.green(`✅ Uploaded to x0.at successfully`));\n      console.log(chalk.yellow(`⚠️  Files kept for 3-100 days (based on size)`));\n      console.log(chalk.gray(`🔓 Note: Files are not encrypted by default`));\n\n      // Clean up temp file\n      await fs.remove(tmpFile);\n\n      return uploadUrl;\n    } catch (error) {\n      // Clean up temp file on error\n      await fs.remove(tmpFile).catch(() => {});\n      throw error;\n    }\n  }\n\n  /**","sourceCodeStart":223,"sourceCodeEnd":259,"githubUrl":"https://github.com/davila7/claude-code-templates/blob/a0851ed10c7c60463dac8cfaaca124cf32d5804d/cli-tool/src/session-sharing.js#L223-L259","documentation":"Thrown by uploadToX0() in cli-tool/src/session-sharing.js when the x0.at file-hosting service returns a response that is empty or does not start with 'http'. The tool uploads a session archive with curl and expects the plain-text share URL on stdout; anything else (an HTML error page, a rate-limit message, an empty body) fails this check. The error message includes whatever was received (or stderr) to help diagnose the service response.","triggerScenarios":"Calling shareSession()/uploadToX0() when x0.at is down, rate-limiting, returns an HTML error page (e.g. '413 Request Entity Too Large'), or when curl fails silently and stdout is empty. Also triggered if the session archive exceeds x0.at's size limit.","commonSituations":"Sharing a very large session file that exceeds x0.at's upload cap; x0.at temporarily offline or behind a maintenance page; corporate proxies stripping the response body; curl not installed so stdout is empty.","solutions":["Check the message payload: if it contains HTML or an error status, x0.at rejected the upload — shrink the session file or retry later","Verify curl is installed and reachable: curl -I https://x0.at","Retry after a short delay — x0.at rate-limits or has transient outages","If the session is large, prune old messages from the session before sharing"],"exampleFix":"// before\nif (!uploadUrl || !uploadUrl.startsWith('http')) {\n  throw new Error(`Invalid response from x0.at: ${uploadUrl || stderr}`);\n}\n\n// after\nif (!uploadUrl || !uploadUrl.startsWith('http')) {\n  throw new Error(`Invalid response from x0.at: ${uploadUrl || stderr || 'empty response (service may be down or file too large)'}`);\n}","handlingStrategy":"retry","validationCode":"const https = require('https');\nhttps.get('https://x0.at', res => console.log('x0.at reachable:', res.statusCode));","typeGuard":null,"tryCatchPattern":"try {\n  const url = await sharer.uploadToX0(file);\n} catch (e) {\n  if (/Invalid response from x0\\.at/.test(e.message)) {\n    await sleep(5000);\n    return retry(attempts - 1); // transient service errors are common\n  }\n  throw e;\n}","preventionTips":["Keep shared session archives small enough for x0.at's limits","Check service availability before batch-sharing sessions","Treat x0.at as best-effort: surface the raw response in the error to the user"],"tags":["network","file-upload","third-party-service","session-sharing"],"backgroundTag":"file-upload-failed","analyzedSha":"a0851ed10c7c60463dac8cfaaca124cf32d5804d","analyzedAt":"2026-08-28T14:11:56.058Z","schemaVersion":2},"datasetVersion":"2026-08-28T16:17:29.566Z"}