Agent Skills: Laravel Best Practices

Laravel Best Practices

Best practices for Laravel, prioritized by impact. Each rule teaches what to do and why. For exact API syntax, verify with search-docs.

Consistency First

Before applying any rule, check what the application already does. Laravel offers multiple valid approaches — the best choice is the one the codebase already uses, even if another pattern would be theoretically better. Inconsistency is worse than a suboptimal pattern.

Check sibling files, related controllers, models, or tests for established patterns. If one exists, follow it — don't introduce a second way. These rules are defaults for when no pattern exists yet, not overrides.

Quick Reference

1. Database Performance → rules/db-performance.md

• Eager load with with() to prevent N+1 queries
• Enable Model::preventLazyLoading() in development
• Select only needed columns, avoid SELECT *
• chunk() / chunkById() for large datasets
• Index columns used in WHERE, ORDER BY, JOIN
• withCount() instead of loading relations to count
• cursor() for memory-efficient read-only iteration
• Never query in Blade templates

2. Advanced Query Patterns → rules/advanced-queries.md

• addSelect() subqueries over eager-loading entire has-many for a single value
• Dynamic relationships via subquery FK + belongsTo
• Conditional aggregates (CASE WHEN in selectRaw) over multiple count queries
• setRelation() to prevent circular N+1 queries
• whereIn + pluck() over whereHas for better index usage
• Two simple queries can beat one complex query
• Compound indexes matching orderBy column order
• Correlated subqueries in orderBy for has-many sorting (avoid joins)

3. Security → rules/security.md

• Define $fillable or $guarded on every model, authorize every action via policies or gates
• No raw SQL with user input — use Eloquent or query builder
• {{ }} for output escaping, @csrf on all POST/PUT/DELETE forms, throttle on auth and API routes
• Validate MIME type, extension, and size for file uploads
• Never commit .env, use config() for secrets, encrypted cast for sensitive DB fields

4. Caching → rules/caching.md

• Cache::remember() over manual get/put
• Cache::flexible() for stale-while-revalidate on high-traffic data
• Cache::memo() to avoid redundant cache hits within a request
• Cache tags to invalidate related groups
• Cache::add() for atomic conditional writes
• once() to memoize per-request or per-object lifetime
• Cache::lock() / lockForUpdate() for race conditions
• Failover cache stores in production

5. Eloquent Patterns → rules/eloquent.md

• Correct relationship types with return type hints
• Local scopes for reusable query constraints
• Global scopes sparingly — document their existence
• Attribute casts in the casts() method
• Cast date columns, use Carbon instances in templates
• whereBelongsTo($model) for cleaner queries
• Never hardcode table names — use (new Model)->getTable() or Eloquent queries

6. Validation & Forms → rules/validation.md

• Form Request classes, not inline validation
• Array notation ['required', 'email'] for new code; follow existing convention
• $request->validated() only — never $request->all()
• Rule::when() for conditional validation
• after() instead of withValidator()

7. Configuration → rules/config.md

• env() only inside config files
• App::environment() or app()->isProduction()
• Config, lang files, and constants over hardcoded text

8. Testing Patterns → rules/testing.md

• LazilyRefreshDatabase over RefreshDatabase for speed
• assertModelExists() over raw assertDatabaseHas()
• Factory states and sequences over manual overrides
• Use fakes (Event::fake(), Exceptions::fake(), etc.) — but always after factory setup, not before
• recycle() to share relationship instances across factories

9. Queue & Job Patterns → rules/queue-jobs.md

• retry_after must exceed job timeout; use exponential backoff [1, 5, 10]
• ShouldBeUnique to prevent duplicates; WithoutOverlapping::untilProcessing() for concurrency
• Always implement failed(); with retryUntil(), set $tries = 0
• RateLimited middleware for external API calls; Bus::batch() for related jobs
• Horizon for complex multi-queue scenarios

10. Routing & Controllers → rules/routing.md

• Implicit route model binding
• Scoped bindings for nested resources
• Route::resource() or apiResource()
• Methods under 10 lines — extract to actions/services
• Type-hint Form Requests for auto-validation

11. HTTP Client → rules/http-client.md

• Explicit timeout and connectTimeout on every request
• retry() with exponential backoff for external APIs
• Check response status or use throw()
• Http::pool() for concurrent independent requests
• Http::fake() and preventStrayRequests() in tests

12. Events, Notifications & Mail → rules/events-notifications.md, rules/mail.md

• Event discovery over manual registration; event:cache in production
• ShouldDispatchAfterCommit / afterCommit() inside transactions
• Queue notifications and mailables with ShouldQueue
• On-demand notifications for non-user recipients
• HasLocalePreference on notifiable models
• assertQueued() not assertSent() for queued mailables
• Markdown mailables for transactional emails

13. Error Handling → rules/error-handling.md

• report()/render() on exception classes or in bootstrap/app.php — follow existing pattern
• ShouldntReport for exceptions that should never log
• Throttle high-volume exceptions to protect log sinks
• dontReportDuplicates() for multi-catch scenarios
• Force JSON rendering for API routes
• Structured context via context() on exception classes

14. Task Scheduling → rules/scheduling.md

• withoutOverlapping() on variable-duration tasks
• onOneServer() on multi-server deployments
• runInBackground() for concurrent long tasks
• environments() to restrict to appropriate environments
• takeUntilTimeout() for time-bounded processing
• Schedule groups for shared configuration

15. Architecture → rules/architecture.md

• Single-purpose Action classes; dependency injection over app() helper
• Prefer official Laravel packages and follow conventions, don't override defaults
• Default to ORDER BY id DESC or created_at DESC; mb_* for UTF-8 safety
• defer() for post-response work; Context for request-scoped data; Concurrency::run() for parallel execution

16. Migrations → rules/migrations.md

• Generate migrations with php artisan make:migration
• constrained() for foreign keys
• Never modify migrations that have run in production
• Add indexes in the migration, not as an afterthought
• Mirror column defaults in model $attributes
• Reversible down() by default; forward-fix migrations for intentionally irreversible changes
• One concern per migration — never mix DDL and DML

17. Collections → rules/collections.md

• Higher-order messages for simple collection operations
• cursor() vs. lazy() — choose based on relationship needs
• lazyById() when updating records while iterating
• toQuery() for bulk operations on collections

18. Blade & Views → rules/blade-views.md

• $attributes->merge() in component templates
• Blade components over @include; @pushOnce for per-component scripts
• View Composers for shared view data
• @aware for deeply nested component props

19. Conventions & Style → rules/style.md

• Follow Laravel naming conventions for all entities
• Prefer Laravel helpers (Str, Arr, Number, Uri, Str::of(), $request->string()) over raw PHP functions
• No JS/CSS in Blade, no HTML in PHP classes
• Code should be readable; comments only for config files

How to Apply

Always use a sub-agent to read rule files and explore this skill's content.

1. Identify the file type and select relevant sections (e.g., migration → §16, controller → §1, §3, §5, §6, §10)
2. Check sibling files for existing patterns — follow those first per Consistency First
3. Verify API syntax with search-docs for the installed Laravel version