[CI] (7c90ff9) next-js/15-app-router-todo

[wizard-ci-bot]

Automated wizard CI run

Trigger ID: 7c90ff9
App: next-js/15-app-router-todo
App directory: apps/next-js/15-app-router-todo
Workbench branch: wizard-ci-7c90ff9-next-js-15-app-router-todo
Wizard branch: feat-skill-based-integration
Examples branch: rearchitect-generator
PostHog (MCP) branch: feat-mcp-skill-deployment
Timestamp: 2026-01-14T21:14:56.127Z
Duration: 307.0s

[wizard-ci-bot]

The app builds successfully. Now I have all the information needed to complete my evaluation.

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PR Evaluation Report

Summary

This PR integrates PostHog analytics into a Next.js 15 App Router Todo application. It adds both client-side and server-side event tracking, configures a reverse proxy to bypass ad blockers, and includes proper error tracking. The implementation follows the recommended Next.js 15.3+ pattern using instrumentation-client.ts.

Files changed	Lines added	Lines removed
9	+571	-2

Confidence score: 4/5 👍

• Missing posthog.identify() implementation: No user identification is implemented, meaning all events will be tracked as anonymous users unless the X-POSTHOG-DISTINCT-ID header is manually passed. This limits the ability to track user journeys across sessions. [MEDIUM]
• Server-side events lack await for posthog.capture(): The server-side PostHog capture calls are not awaited, which could lead to events being dropped on serverless/edge environments where the function may terminate before the event is sent. Consider using await posthog.capture() or await posthog.flush(). [MEDIUM]
• .env file committed to PR: The .env file with the PostHog key is included in the changed files list but was not shown in the diff. Ensure this file is in .gitignore to prevent committing API keys. [MEDIUM]

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File changes

Filename	Score	Description
app/api/todos/[id]/route.ts	4/5	Adds server-side PostHog tracking for PATCH and DELETE operations. Captures success and error events with relevant properties. Uses anonymous fallback for distinctId.
app/api/todos/route.ts	4/5	Adds server-side tracking for POST (todo creation) with error tracking. Same pattern as the [id] route.
components/todos/todo-list.tsx	4/5	Adds client-side event tracking for all todo operations (create, complete, uncomplete, delete, fetch error). Clean integration that doesn't disrupt existing logic.
instrumentation-client.ts	4/5	New file implementing PostHog client initialization using the correct Next.js 15.3+ pattern. Includes capture_exceptions: true for error tracking. Uses defaults: '2025-05-24' which is a valid configuration option.
lib/posthog-server.ts	3/5	Singleton pattern for server-side PostHog client. Uses flushAt: 1 and flushInterval: 0 which forces immediate flush - good for serverless but may have performance implications. Debug mode is always on.
next.config.ts	5/5	Properly configured reverse proxy rewrites for PostHog ingestion. Includes skipTrailingSlashRedirect as required.
package.json	5/5	Correctly adds posthog-js and posthog-node dependencies with appropriate versions.
pnpm-lock.yaml	5/5	Lock file updated with PostHog dependencies and their transitive dependencies.
posthog-setup-report.md	4/5	Comprehensive documentation of the integration with suggested insights. Minor issue: references a .claude/skills/ folder that wasn't included in the PR.

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App sanity check: 4/5 ✅

Criteria	Result	Description
App builds and runs	Yes	Build completes successfully with next build
Preserves existing env vars & configs	Yes	Only adds PostHog-related config, doesn't modify existing app logic
No syntax or type errors	Yes	TypeScript compilation passes without errors
Correct imports/exports	Yes	All imports are valid and properly structured
Minimal, focused changes	Yes	Changes are focused on PostHog integration without unnecessary modifications

Issues

• .env file potentially committed: The report mentions .env was created, but it should be in .gitignore. Sensitive API keys should not be committed. [MEDIUM]
• Debug mode always enabled on server: posthog-server.ts has posthogClient.debug(true) unconditionally, which may cause verbose logging in production. [LOW]

Other completed criteria

• Clear, readable code with appropriate comments
• Consistent with existing patterns in the codebase
• Appropriate error handling in API routes
• Environment variables documented in setup report
• Build configuration is valid and functional

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PostHog implementation: 4/5 ✅

Criteria	Result	Description
PostHog SDKs installed	Yes	posthog-js@^1.321.2 and posthog-node@^5.21.0 added
PostHog client initialized	Yes	Client-side via instrumentation-client.ts, server-side via singleton in lib/posthog-server.ts
capture()	Yes	Multiple capture calls for todo CRUD operations on both client and server
identify()	No	No user identification implemented; uses anonymous distinctId fallback
Error tracking	Yes	capture_exceptions: true enabled, plus manual api_error events
Reverse proxy	Yes	Properly configured in next.config.ts with /ingest rewrites

Issues

• No posthog.identify() implementation: Events are captured without user identification. Server-side relies on X-POSTHOG-DISTINCT-ID header which isn't sent by the client. This means client and server events won't be linked to the same user. [MEDIUM]
• Server events not awaited: The posthog.capture() calls in API routes are not awaited, risking event loss in serverless environments. [MEDIUM]

Other completed criteria

• Correct API host configuration using reverse proxy
• PostHog initialization with API key from environment variables
• Captures baseline custom events for user actions
• No PII in event properties (only todo_id and metadata)
• Proper cleanup function exported (shutdownPostHog)
• Session replay automatically enabled via defaults

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PostHog insights and events: 4/5 ✅

Filename	PostHog events	Description
todo-list.tsx	todo_created, todo_completed, todo_uncompleted, todo_deleted, todos_fetch_error	Client-side events tracking full CRUD lifecycle with todo_id properties
app/api/todos/route.ts	server_todo_created, api_error	Server-side creation tracking with has_description property
app/api/todos/[id]/route.ts	server_todo_updated, server_todo_deleted, api_error	Server-side update/delete tracking with fields_updated property
instrumentation-client.ts	capturedException (automatic)	Automatic exception capture for unhandled errors

Issues

• Duplicate client/server events: Both client and server track the same operations (e.g., todo_created and server_todo_created). While this provides redundancy, it could cause confusion in analytics. Consider documenting which events to use for which insights. [LOW]
• Missing pageview tracking: No explicit pageview tracking implemented (though PostHog may auto-capture these with defaults). [LOW]

Other completed criteria

• Events capture real user actions and product flows
• Events include relevant properties (todo_id, has_description, fields_updated, error_message)
• Events support funnel analysis (todo_created → todo_completed)
• Error tracking enables monitoring API health
• Events are enriched with source property for distinguishing client vs server

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Reviewed by wizard workbench PR evaluator