Overview
Subagent-Driven Development executes implementation plans by dispatching a fresh subagent for each task, followed by two-stage review: spec compliance first, then code quality.Core principle: Fresh subagent per task + two-stage review (spec then quality) = high quality, fast iteration
When to Use
Use when:- You have an implementation plan from Writing Plans
- Tasks are mostly independent
- You want to stay in the current session (not switch to parallel session)
- Same session (no context switch)
- Fresh subagent per task (no context pollution)
- Two-stage review after each task
- Faster iteration (no human-in-loop between tasks)
The Process
Read Plan and Create Todos
- Read plan file once:
docs/plans/YYYY-MM-DD-feature.md - Extract all tasks with full text and context
- Create TodoWrite with all tasks
Read the plan file once upfront. Extract all task details so you can provide them to subagents without making them read the file.
Dispatch Implementer Subagent
Use
./implementer-prompt.md template to dispatch subagent with:- Full task text (already extracted)
- Context about where task fits
- Scene-setting (what’s already built, what this adds)
- May ask questions before starting
- Implements following TDD
- Tests the implementation
- Commits the changes
- Self-reviews the code
- Answer clearly and completely
- Provide additional context if needed
- Let them proceed once answered
Dispatch Spec Compliance Reviewer
Use
./spec-reviewer-prompt.md template to dispatch reviewer:- Provide task spec
- Provide what was implemented
- ✅ All spec requirements met
- ✅ Nothing extra added (no YAGNI violations)
- ❌ Lists any missing requirements
- ❌ Lists any extra features
- Implementer (same subagent) fixes them
- Spec reviewer reviews again
- Repeat until ✅
Dispatch Code Quality Reviewer
Use
./code-quality-reviewer-prompt.md template:- Provide git SHAs for the changes
- Ask for code quality assessment
- Strengths of implementation
- Issues (Important / Minor / Nitpick)
- Approval or required changes
- Implementer fixes them
- Code reviewer reviews again
- Repeat until approved
Visual Workflow
Prompt Templates
The skill includes three prompt templates:Implementer
./implementer-prompt.mdDispatch to implement task with TDDSpec Reviewer
./spec-reviewer-prompt.mdVerify implementation matches specCode Quality Reviewer
./code-quality-reviewer-prompt.mdAssess code quality and suggest improvementsExample Workflow
Complete Multi-Task Example
Complete Multi-Task Example
Advantages
vs. Manual Execution
- Subagents follow TDD naturally
- Fresh context per task (no confusion)
- Parallel-safe (subagents don’t interfere)
- Subagent can ask questions (before AND during work)
vs. Executing Plans
- Same session (no handoff)
- Continuous progress (no waiting)
- Review checkpoints automatic
Efficiency Gains
- No file reading overhead (controller provides full text)
- Controller curates exactly what context is needed
- Subagent gets complete information upfront
- Questions surfaced before work begins (not after)
Quality Gates
- Self-review catches issues before handoff
- Two-stage review: spec compliance, then code quality
- Review loops ensure fixes actually work
- Spec compliance prevents over/under-building
- Code quality ensures implementation is well-built
Cost
Higher invocation cost:- More subagent invocations (implementer + 2 reviewers per task)
- Controller does more prep work (extracting all tasks upfront)
- Review loops add iterations
Red Flags
Never:- Start implementation on main/master branch without explicit user consent
- Skip reviews (spec compliance OR code quality)
- Proceed with unfixed issues
- Dispatch multiple implementation subagents in parallel (conflicts)
- Make subagent read plan file (provide full text instead)
- Skip scene-setting context (subagent needs to understand where task fits)
- Ignore subagent questions (answer before letting them proceed)
- Accept “close enough” on spec compliance (spec reviewer found issues = not done)
- Skip review loops (reviewer found issues = implementer fixes = review again)
- Let implementer self-review replace actual review (both are needed)
- Start code quality review before spec compliance is ✅ (wrong order)
- Move to next task while either review has open issues
Handling Issues
If Subagent Asks Questions
- Answer clearly and completely
- Provide additional context if needed
- Don’t rush them into implementation
- Questions are good - they prevent wrong work
If Reviewer Finds Issues
- Implementer (same subagent) fixes them
- Reviewer reviews again
- Repeat until approved
- Don’t skip the re-review
If Subagent Fails Task
- Dispatch fix subagent with specific instructions
- Don’t try to fix manually (context pollution)
- Provide clear context about what failed and why
Checklist
Per task:- Extracted task text and context upfront
- Dispatched implementer with complete information
- Answered any questions before proceeding
- Implementer completed (implemented, tested, committed, self-reviewed)
- Dispatched spec compliance reviewer
- Spec reviewer approved (or issues fixed and re-reviewed)
- Dispatched code quality reviewer (only after spec ✅)
- Code reviewer approved (or issues fixed and re-reviewed)
- Marked task complete in TodoWrite
- Dispatched final code reviewer
- Used finishing-a-development-branch skill
Related Skills
- Writing Plans: Creates the plan this skill executes
- Executing Plans: Alternative for parallel session execution
- Test-Driven Development: Subagents use TDD for implementation