d-o-hub Task Decomposition
When to Use
- Complex multi-step tasks (3+ distinct actions)
- Tasks requiring multiple files or modules
- Work that could be parallelized across agents
- Unclear implementation path
- Before spawning an agent team
Process
1. Define Outcome
- What does "done" look like?
- Acceptance criteria
- Verification method
2. Identify Subtasks
- List all discrete work items
- Mark blockers/dependencies
- Estimate relative effort (S/M/L)
3. Order by Dependency
- Draw dependency graph
- Identify parallelizable work
- Sequence blocking tasks first
4. Validate Completeness
- Does completing all subtasks achieve the outcome?
- Are there hidden dependencies?
- Is effort estimate realistic?
Work Breakdown Structure
| Size | Lines Changed | Files | Time Est. |
|---|---|---|---|
| S | < 50 | 1-2 | < 30 min |
| M | 50-200 | 2-4 | 30-90 min |
| L | > 200 | 4+ | > 90 min |
Dependency Patterns
Sequential (Blocking Chain)
Task A (no deps) → Task B (depends on A) → Task C (depends on B)
Use addBlockedBy to enforce order.
Parallel (Independent)
Task A ─┐
Task B ─┼─→ Integration Task (depends on A, B, C)
Task C ─┘
Tasks A, B, C can run concurrently.
Mixed
Task A → Task B ─┐
├─→ Task E
Task C → Task D ─┘
Example Decomposition
Task: "Add export/import feature for concepts"
| ID | Subtask | Depends On | Size | Owner |
|---|---|---|---|---|
| 1 | Design JSON schema for export | - | S | - |
| 2 | Implement exporter in persistence.rs | 1 | M | - |
| 3 | Implement importer in persistence.rs | 1 | M | - |
| 4 | Add CLI commands (export/import) | 2, 3 | M | - |
| 5 | Write integration tests | 4 | M | - |
| 6 | Update documentation | 4 | S | - |
Task Blocking with TaskUpdate
TaskUpdate(taskId: "5", addBlockedBy: ["4"]) // Tests wait for CLI
TaskUpdate(taskId: "4", addBlockedBy: ["2", "3"]) // CLI waits for impl
Anti-Patterns
| Avoid | Instead |
|---|---|
| Vague tasks ("fix stuff") | Specific outcome ("reduce bench time by 20%") |
| Missing dependencies | Explicit addBlockedBy calls |
| Giant tasks | Split into S/M subtasks |
| Circular dependencies | Re-plan the breakdown |
Verification Checklist
- Each task has clear acceptance criteria
- Dependencies are explicit (not assumed)
- No task depends on itself (directly or transitively)
- Parallel tasks identified for team efficiency
- Integration/verification task included