skills/specs/001-screenshot-analysis/COMPARISON.md

Specification vs Implementation: A Reality Check

The Numbers

Metric	Original Spec	Minimal Implementation	Ratio
Total Lines	635 lines	185 lines	3.4x
Specification	635 lines	83 lines (SKILL.md)	7.6x
Implementation	0 lines (not started)	22 lines (bash script)	∞
Task Breakdown	82 tasks	0 tasks (just built it)	∞

Key insight: 635 lines of planning to describe 22 lines of code.

What We Specified

Original spec included:

• 11 functional requirements (FR-001 through FR-010)
• 3 prioritized user stories with acceptance scenarios
• 5 success criteria with measurable outcomes
• Configuration system (JSON files)
• Time-based filtering ("screenshot from 5 minutes ago")
• Nth screenshot lookup ("second-to-last screenshot")
• Symlink handling policy
• Comprehensive error handling
• 82 implementation tasks
• 4 separate bash scripts
• Full test coverage with bats
• Data models and contracts

What we actually needed:

• Find latest file: ls -t ~/Pictures/Screenshots/*.png | head -1
• Handle errors: Check if directory exists and has files
• Done

What We Built

Minimal implementation:

• 1 SKILL.md file (agent instructions)
• 1 bash script (22 lines including comments)
• 1 README (user documentation)
• 1 example output

Features supported:

• ✅ Find latest screenshot
• ✅ Clear error messages
• ✅ Standard formats (PNG, JPG, JPEG)
• ✅ Works immediately
• ✅ Zero configuration

Features NOT supported (and that's OK):

• ❌ Custom directories
• ❌ Nth screenshot lookup
• ❌ Time-based filtering
• ❌ Configuration files
• ❌ Symlink handling policy

Time Analysis

Specification process:

• Session 1: Wrote spec.md (~30 minutes)
• Session 2: Clarified ambiguities (~15 minutes)
• Session 3: Created plan.md (~30 minutes)
• Session 4: Generated tasks.md (~20 minutes)
• Session 5: Analyzed over-engineering (~20 minutes)
• Total: ~115 minutes

Implementation:

• Wrote SKILL.md (~10 minutes)
• Wrote find-latest.sh (~5 minutes)
• Wrote README.md (~5 minutes)
• Tested (~2 minutes)
• Total: ~22 minutes

Ratio: 5.2x more time spent on specification than implementation

Root Cause Analysis

What Went Wrong

1. Template-Driven Development

   • Used /speckit.specify tool without scope calibration
   • Answered every template question instead of questioning the template
   • Treated "specification" as a deliverable rather than a tool

2. Solution-First Thinking

   • Jumped to "how to find files properly" before validating "is file-finding the problem"
   • Designed abstractions before writing concrete code
   • Optimized for extensibility we don't need

3. Over-Engineering Bias

   • Added features user didn't request (time filtering, Nth lookup)
   • Created configuration system for single hard-coded value
   • Planned comprehensive test coverage for 22-line script

4. Lost Sight of Value

   • User wanted: "Don't make me type paths"
   • We delivered: "Comprehensive screenshot management framework"
   • Forgot to ask: "What's the simplest thing that works?"

What Went Right (After Reset)

1. Reality Check

   • Tested actual command: ls -t | head -1 (works instantly)
   • Counted spec lines: 635 (ridiculous for this problem)
   • Asked: "What are we actually solving?"

2. Scope Reduction

   • Removed all SHOULD requirements
   • Removed all "future enhancement" features
   • Focused on single use case: "find latest screenshot"

3. Build First, Plan Second

   • Wrote the script (22 lines)
   • Tested it (works)
   • Documented it (SKILL.md + README)
   • Shipped it

Lessons Learned

For Specifications

Do:

• ✅ Start with one-liner proof of concept
• ✅ Validate the problem is real before solving it
• ✅ Test actual commands before designing abstractions
• ✅ Question every requirement: "What if we didn't do this?"
• ✅ Write code first, plan later for small problems

Don't:

• ❌ Fill in specification templates without scope calibration
• ❌ Add features user didn't request
• ❌ Optimize for hypothetical future needs
• ❌ Create configuration systems for constants
• ❌ Break down tasks before trying the task

For Development

Do:

• ✅ Solve the specific problem user described
• ✅ Use simplest solution that works
• ✅ Ship quickly, iterate on feedback
• ✅ Document limitations clearly
• ✅ Make it easy to enhance later IF needed

Don't:

• ❌ Build extensibility before you need it
• ❌ Abstract before you have concrete examples
• ❌ Add configuration before you have variations
• ❌ Plan comprehensive testing before you have code
• ❌ Assume you know what users will ask for

Decision Framework

When deciding whether to specify or implement first:

Is the solution obvious?
├─ YES → Write code first (this case)
│         └─ Spec is just documentation of what you built
└─ NO  → Write spec first
          ├─ Multiple teams need coordination
          ├─ Complex domain requiring analysis
          ├─ High risk of rework
          └─ Unclear requirements needing clarification

For this problem:

• Solution obvious? YES (ls -t | head -1)
• Multiple teams? NO (just me)
• Complex domain? NO (file system operations)
• Risk of rework? LOW (22 lines of bash)
• Unclear requirements? NO (user described exact problem)

Verdict: Should have written code first.

Success Metrics (Revised)

Original success criteria:

• SC-001: Work in 100% of cases (unmeasurable without usage data)
• SC-002: Complete in <1 second for 1000 files (premature optimization)
• SC-003: Succeed in 95% of requests (can't measure before shipping)
• SC-004: Clear error messages (this is good, kept it)
• SC-005: Save 40+ keystrokes (accurate but overcomplicated)

Actual success metric:

• User says: "look at my screenshot"
• AI responds:
• User says: "thanks" (not "that's not the right file")

That's it. That's the only metric that matters.

Recommendation for Future

When given a user request like "make it so I don't have to type paths":

1. Immediately test: Try one-liner solution
2. If it works: Ship it with documentation
3. If it doesn't: THEN write specification

For this problem:

# Time to validate solution: 5 seconds
ls -t ~/Pictures/Screenshots/*.png | head -1

# Time to specify properly: 115 minutes
# Time to implement: 22 minutes
# Time wasted: 93 minutes

Final Thoughts

The best spec is often the code itself.

For simple problems:

• Code is the specification
• Tests are the acceptance criteria
• README is the user story
• Working software is the proof

Save comprehensive specifications for when you actually need them:

• Coordinating multiple developers
• Uncertain problem domains
• High-risk architectural decisions
• Compliance/audit requirements

Not for 22-line bash scripts.

---

This document intentionally created AFTER implementation, not before.