Cursor Background Agents & Bugbot Technical Reference

Configuration That Works

Background Agents Setup

• Requirement: Privacy Mode must be DISABLED - agents need cloud access to function
• Repository Size Limit: Best performance under 50k lines of code
• Context Window: ~200k tokens maximum for complex tasks
• Branch Strategy: Agents create cursor-agent-fix-[timestamp] branches automatically

Essential Files

.cursorignore          # Exclude node_modules, .git, dist, build, coverage, *.log, .env*
.cursorrules           # Project-specific coding standards and patterns

GitHub Integration Requirements

1. Cursor GitHub app needs write permissions to specific repositories
2. PR templates configured in dashboard or auto-generation fails
3. Personal access tokens as fallback for permission issues

Resource Requirements

Performance Costs

• Simple tasks: 1-5 minutes, $0.50-2.00
• Medium refactoring: 10-30 minutes, $5-15
• Complex features: 30+ minutes, $15-50+
• Failed attempts: Still incur costs - confused agents spinning for hours still charge

Time Investment

• Setup: 2-4 hours initial configuration for team workflows
• Learning curve: 1 month for developers to understand effective prompting
• Maintenance: Weekly Cursor restarts needed for memory management

Hardware Requirements

• Memory: 16GB+ recommended for large codebases
• Network: Constant internet required - no meaningful offline mode
• Indexing: 8+ minutes for 200k+ line codebases

Critical Warnings

What Documentation Doesn't Tell You

Agent Over-Engineering Pattern

• Agents interpret "add logging" as implementing Winston + CloudWatch + dashboards
• Solution: Hyper-specific prompts with explicit constraints

Silent Failures

• Agents fail without clear error messages
• Indicators: Stuck "analyzing" for 20+ minutes, permission denied errors
• Fix: Kill and restart with smaller scope

Context Limits Hit Production Systems

• UI breaks at 1000 spans making debugging distributed transactions impossible
• Large codebases cause agents to miss critical file relationships
• Workaround: Manual file selection using @filename.ts syntax

Breaking Points

Codebase Complexity Thresholds

• Works: Simple repos, clear separation of concerns
• Fails: Monorepos with complex build systems, shared dependencies
• Breaking point: Workspaces requiring specific build commands

Privacy vs Functionality Trade-off

• Background Agents fundamentally incompatible with Privacy Mode
• Decision criteria: Choose privacy OR advanced features, not both
• Enterprise impact: Compliance requirements may eliminate key features

Implementation Reality

Success Scenarios (60% reliability)

• Memory leak detection in connection handling
• Race condition identification in async code
• SQL injection vulnerability detection
• N+1 query performance issues

Failure Scenarios (40% false positives)

• Flags intentional code patterns as bugs
• Misunderstands business logic context
• Suggests changes that break existing functionality
• Confused by advanced TypeScript patterns

Prompting Techniques That Work

// Effective prompt structure
Context: [Specific technology stack]
Files involved: @specific/file.ts @related/component.tsx
Constraints: Don't modify database schema, follow existing auth pattern
Task: [Single, focused objective]
Success criteria: [Measurable outcome]

Team Workflow Integration

1. Bugbot: Initial syntax/security review (60% accuracy)
2. Human review: Business logic and architecture decisions
3. CI/CD gates: All tests must pass before merge
4. Extra scrutiny: Agent-generated code requires senior review

Troubleshooting Decision Tree

"Context Too Large" Errors

1. Create comprehensive .cursorignore file
2. Exclude generated files, vendor code, files >1MB
3. Break requests into 15-minute focused tasks
4. Use codebase filters for large repositories

GitHub Permission Issues

1. Check GitHub Settings → Applications → Cursor permissions
2. Verify write access to specific repositories
3. Disconnect/reconnect GitHub integration in dashboard
4. Create personal access token with repo permissions as fallback

Agent Stuck in Analysis

• Timeout: Kill after 20+ minutes of "analyzing"
• Root cause: Codebase too complex or prompt too vague
• Fix: Reduce scope to single file/component level

Cost Overruns

• Monitor: Set usage alerts at $50, $100, $150 intervals
• Heavy user threshold: $200/month indicates need for Pro Plus ($70/month)
• Prevention: Specific prompts prevent confused retries

Comparative Analysis

Feature	Marketing Promise	Production Reality	Workaround Required
Background Processing	"Work while you focus elsewhere"	Works for simple tasks only	15-minute task chunks
GitHub Integration	"Seamless PR creation"	Templates ignored, permissions break	Manual PR review required
Bugbot Analysis	"Catches bugs humans miss"	60% accuracy rate	Custom rules + ignore comments
Context Understanding	"Understands entire codebase"	Token limits cause missed relationships	Manual file references
Cost Predictability	"Request-based pricing"	Failed attempts still charge	Usage monitoring essential

When AI Becomes Counterproductive

Use AI For

• Boilerplate code generation
• Refactoring existing code patterns
• Test generation for existing functions
• Documentation from existing code
• Simple bugs with clear reproduction

Manual Implementation Required

• Complex business logic requiring domain knowledge
• Performance-critical code paths
• Security-sensitive operations
• Novel algorithms or architectural decisions
• Legacy system integration

Decision Criteria

• AI Appropriate: Task can be completed by following existing patterns
• Manual Required: Task requires understanding user intent beyond literal prompt

Enterprise Deployment Constraints

SSO Integration Reality

• Setup time: 24 hours for large organizations
• User provisioning: Manual admin approval required
• Permission levels: Specific enterprise features need elevated access

Compliance Impact

• Privacy Mode: Eliminates Background Agents entirely
• Data residency: All processing happens in Cursor cloud
• SOC 2: Available but limits some functionality

Team Management Essentials

• Shared configuration: .cursorrules files in every repository
• Usage monitoring: Track token consumption by team member
• Cost allocation: Budget planning requires usage pattern analysis
• Onboarding: 1-month supervision period for new developers