Monitoring Skill
Monitor Vercel deployments, check logs, and track errors.
Viewing Logs
Vercel Dashboard
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Go to Vercel Dashboard → Project → Logs
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Filter by:
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Function logs
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Build logs
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Edge function logs
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Time range
Vercel CLI
View recent logs
vercel logs <deployment-url>
Stream logs in real-time
vercel logs <deployment-url> --follow
Filter by status
vercel logs <deployment-url> --status error
Vercel Analytics
Web Vitals
Monitor in Vercel Dashboard → Analytics:
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LCP (Largest Contentful Paint)
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FID (First Input Delay)
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CLS (Cumulative Layout Shift)
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TTFB (Time to First Byte)
Speed Insights
Already integrated in the app:
// apps/web/src/app/layout.tsx import { Analytics } from "@vercel/analytics/next"; import { SpeedInsights } from "@vercel/speed-insights/next";
const RootLayout = ({ children }) => ( <html> <body> {children} <Analytics /> <SpeedInsights /> </body> </html> );
Logging Patterns
The codebase uses standard console.log/error/warn for logging:
// Workflow logging pattern console.log("[WORKFLOW] Posts cache invalidated"); console.log("[COE]", coeResult);
// Error logging pattern console.error("Error getting post view count:", error); console.error("Download failed:", { url, status });
Log Prefixes Used:
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[WORKFLOW]
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Workflow execution events
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[COE]
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COE data processing
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[CARS]
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Car data processing
Health Checks
The app has a health check endpoint at /api/health :
// apps/web/src/app/api/health/route.ts export const GET = () => { return NextResponse.json( { status: "ok", timestamp: new Date().toISOString() }, { status: 200, headers: { "Cache-Control": "public, s-maxage=60, stale-while-revalidate=300", }, }, ); };
Test health endpoint:
curl -f https://sgcarstrends.com/api/health || echo "Web unhealthy"
Workflow Error Handling
Workflows use Vercel WDK's built-in error handling:
// apps/web/src/workflows/cars/index.ts import { FatalError, RetryableError } from "workflow";
// Retryable errors (will be retried automatically) if (message.includes("429")) { throw new RetryableError("AI rate limited", { retryAfter: "1m" }); }
// Fatal errors (will not be retried) if (message.includes("401") || message.includes("403")) { throw new FatalError("AI authentication failed"); }
Error Types:
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RetryableError
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Temporary failures (rate limits, network issues)
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FatalError
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Permanent failures (auth errors, invalid config)
Debugging Production Issues
- Check Vercel Logs
Get deployment URL
vercel ls
Check logs
vercel logs <url> --follow
- Check Build Output
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Vercel Dashboard → Deployments
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Click on deployment
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View "Build Logs"
- Test Endpoint
curl -v https://sgcarstrends.com/api/health
- Check Function Runtime
Vercel Dashboard → Project → Settings → Functions
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View runtime version
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Check memory allocation
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Review timeout settings
Common Issues
Issue Investigation Solution
High latency Check Vercel Analytics, slow queries Optimize queries, add caching
Build failures Check build logs Fix build errors, update dependencies
Function timeout Check function logs Optimize code, increase timeout
Cold starts Check function invocations Consider edge functions
Workflow failures Check Vercel logs for workflow ID Review error type, check retries
Vercel Function Configuration
// API route config export const config = { maxDuration: 60, // seconds (Pro plan allows up to 60s) };
Cron Job Monitoring
Workflows are triggered by Vercel Cron:
// apps/web/vercel.json { "crons": [ { "path": "/api/workflows/cars", "schedule": "0 10 * * *" }, { "path": "/api/workflows/coe", "schedule": "0 10 * * *" }, { "path": "/api/workflows/deregistrations", "schedule": "0 10 * * *" } ] }
Monitor cron executions:
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Vercel Dashboard → Project → Cron Jobs
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View execution history and status
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Check logs for each execution
Best Practices
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Use Log Prefixes: Add [CONTEXT] prefix for easy filtering
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Log Meaningful Data: Include relevant context (month, record counts)
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Don't Log Secrets: Never log passwords, tokens, API keys
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Use Vercel Analytics: Monitor performance metrics
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Check Cron Jobs: Monitor scheduled workflow executions
References
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Vercel Logs: https://vercel.com/docs/observability/runtime-logs
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Vercel Analytics: https://vercel.com/docs/analytics
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Speed Insights: https://vercel.com/docs/speed-insights
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Vercel Cron Jobs: https://vercel.com/docs/cron-jobs