debug-using-debugbar

name	debug-using-debugbar
description	Use this skill to optimize requests or debug Laravel application issues — slow pages, N+1 queries, exceptions, failed requests, or unexpected behavior — by inspecting data captured by Laravel Debugbar via Artisan CLI commands. Use when the user asks to investigate a bug, diagnose a slow request, find duplicate queries, check what happened on a previous request, or optimize database performance, even if they don't explicitly mention "debugbar" or "profiling."
compatibility	Requires Laravel with fruitcake/laravel-debugbar installed and debug mode enabled.

Debugging and optimizing workflow

1. Find the relevant request:

   php artisan debugbar:find --issues --max=50
   

2. Inspect the request summary to identify which collectors have data:

   php artisan debugbar:get {id}
   

3. Drill into the relevant collector based on the issue type:

   php artisan debugbar:get {id} --collector=exceptions
   

4. For query issues, use dedicated query analysis:

   php artisan debugbar:queries {id}
   

5. Trace the problem to source code using backtraces, then fix and re-test.

Finding requests

# List recent requests (shows summary with status, duration, memory, query count)
php artisan debugbar:find

# Filter by URI pattern (fnmatch) and/or HTTP method
php artisan debugbar:find --uri="/api/*" --method=POST

# Only show requests with issues (exceptions, slow queries, duplicates, errors)
php artisan debugbar:find --issues --max=50

# Customize issue thresholds (defaults: --min-queries=50, --min-duration=1000, --min-duplicates=2)
php artisan debugbar:find --issues --min-queries=10 --min-duration=500

# Threshold options also work standalone, filtering on just that criteria
php artisan debugbar:find --min-queries=20

--issues flags: exceptions, non-2xx status, high query count, slow queries, duplicate query groups, slow request duration, and failed queries. Issue filtering applies on top of the fetched result set — increase --max to scan further back.

Inspecting a request

# Summary of all collectors (available collectors depend on config)
php artisan debugbar:get latest
php artisan debugbar:get {id}

# Full data for a specific collector
php artisan debugbar:get {id} --collector=exceptions

Pick the collector by issue type:

• Error/500 → exceptions · Slow page → queries, time · Auth → auth, gate · Cache → cache

Analyzing queries

# Overview with duplicate detection and slow query flags
php artisan debugbar:queries {id}

# Backtrace and params for a specific statement
php artisan debugbar:queries {id} --statement=N

# EXPLAIN plan or re-execute a SELECT
php artisan debugbar:queries {id} --statement=N --explain
php artisan debugbar:queries {id} --statement=N --result

Duplicate queries are a strong N+1 signal. Use --statement=N to get the backtrace and find the origin.

Gotchas

• Always start with debugbar:find --issues rather than debugbar:find — the issue flags surface the most actionable requests immediately.
• The {id} is the request ID from the debugbar:find output, or use latest to inspect the most recent request.
• Collector availability depends on the app's debugbar config — the summary from debugbar:get shows which collectors have data.
• --explain and --result only work on SELECT queries. They re-execute against the current database, so results may differ from the original request.
• debugbar:clear removes all stored data — use it to reset between debugging sessions, not mid-investigation.