Blueprint

A spec-first development workflow that iterates through spec → implement → verify → simplify phases using subagents.

Philosophy

•Spec first: A detailed spec prevents wasted iterations
•Parallel work: Subagents handle discrete tasks concurrently
•Verification built-in: Every implementation gets tested and reviewed
•Simplify last: Reduce complexity only after correctness is proven

Workflow Overview

code

┌─────────────┐     ┌─────────────────┐     ┌─────────────────┐     ┌─────────────┐
│  1. SPEC    │ ──▶ │  2. IMPLEMENT   │ ──▶ │   3. VERIFY     │ ──▶ │ 4. SIMPLIFY │
│  (with user)│     │  (subagents)    │     │   (subagents)   │     │ (subagents) │
└─────────────┘     └─────────────────┘     └─────────────────┘     └─────────────┘
      │                     │                       │                      │
      ▼                     ▼                       ▼                      ▼
  spec.md            implementation           test results           simplified
  approved              complete              + review notes            code

Phase 1: Spec Writing

Collaborate with user to produce a detailed spec. Write to spec.md in project root.

Spec Template

markdown

# Feature: [Name]

## Problem Statement
[What problem does this solve? Why now?]

## Success Criteria
- [ ] [Measurable criterion 1]
- [ ] [Measurable criterion 2]

## Scope
### In Scope
- [Feature/behavior 1]

### Out of Scope  
- [Explicitly excluded item]

## Technical Approach
### Architecture
[How components fit together]

### Key Decisions
| Decision | Choice | Rationale |
|----------|--------|-----------|
| [Decision] | [Choice] | [Why] |

## Implementation Tasks
- [ ] Task 1: [Description] (~estimate)
- [ ] Task 2: [Description] (~estimate)

## Test Plan
- [ ] Unit: [What to test]
- [ ] Integration: [What to test]

## Risks & Mitigations
| Risk | Mitigation |
|------|------------|
| [Risk] | [Mitigation] |

Ask clarifying questions until spec is complete. Get explicit user approval before Phase 2.

Phase 2: Implementation (Subagents)

Spawn subagents for each implementation task. Use Task.run() or equivalent subagent API.

Subagent Prompt Template

code

You are implementing a specific task from a spec.

TASK: [Task description from spec]
CONTEXT: [Relevant architecture/decisions from spec]
FILES TO CREATE/MODIFY: [Specific files]
SUCCESS CRITERIA: [How to know this task is done]

Instructions:
1. Read the full spec at spec.md first
2. Implement ONLY the assigned task
3. Write tests alongside implementation
4. Commit with message: "feat: [task summary]"
5. Output TASK_COMPLETE when done, or BLOCKED: [reason] if stuck

Parallelization Strategy

•Independent tasks → spawn in parallel
•Tasks with dependencies → spawn sequentially or chain
•Shared state → spawn serially with explicit handoff

Track progress:

markdown

## Implementation Progress
- [x] Task 1 - COMPLETE (agent-1)
- [ ] Task 2 - IN_PROGRESS (agent-2)  
- [ ] Task 3 - BLOCKED: waiting on Task 2

Phase 3: Verification (Subagents)

Spawn verification subagents in parallel:

Test Runner Subagent

code

Run all tests for the implementation.
1. Execute test suite
2. Report: TESTS_PASS or TESTS_FAIL with details
3. If failing, list specific failures

Code Reviewer Subagent

code

Review implementation against spec.md.
Check:
- All success criteria met
- No scope creep beyond spec
- Error handling present
- Edge cases covered

Output: REVIEW_PASS or REVIEW_ISSUES: [list]

Type/Lint Checker Subagent

code

Run type checker and linter.
Report any errors or warnings.
Output: CLEAN or ISSUES: [list]

Verification Gate

All three must pass to proceed. If any fail:

•Spawn fix subagent with specific issues
•Re-run failed verification
•Repeat until all pass (max 5 iterations)

Phase 4: Simplification (Subagents)

Only after verification passes. Spawn simplification subagents:

Complexity Reducer

code

Review implementation for unnecessary complexity.
Look for:
- Dead code
- Over-abstraction
- Redundant logic
- Verbose patterns with simpler alternatives

Propose specific simplifications. Do not change behavior.

Documentation Cleaner

code

Review comments and docs.
Remove:
- Obvious comments
- Stale TODOs
- Redundant docstrings

Add only where genuinely unclear.

After simplification: re-run Phase 3 verification to ensure nothing broke.

Completion

When all phases complete:

•Summarize what was built
•List any deferred items for future
•Output: BLUEPRINT_COMPLETE

Iteration Limits

Phase	Max Iterations	On Limit
Spec	N/A (user-driven)	-
Implement	3 per task	Mark BLOCKED, continue
Verify	5 total	Report remaining issues
Simplify	2	Accept current state

Quick Reference

bash

# Check spec exists and is approved
cat spec.md | head -50

# Spawn implementation subagent
Task.run("Implement [task] per spec.md...")

# Run verification suite
Task.run("Run tests...") & Task.run("Review code...") & Task.run("Check types...")

# Simplification pass  
Task.run("Simplify implementation, preserve behavior...")