v1.0.0 - Initial Release

Date Validation Skill v1.0.0

Prevents day-of-week errors, countdown math mistakes, and timeline inconsistencies in Claude Code.

Features

✓ Two-source ground truth verification - Cross-validates env tag + system date
✓ Day-of-week matching - Catches "Wed Nov 12" when Nov 12 is Tuesday
✓ Relative date calculations - Validates "today", "tomorrow", "in X days"
✓ Countdown math - Verifies "18 days until Dec 1" accuracy
✓ Comprehensive scanning - Checks ALL dates, not just obvious errors
✓ Individual validation - Validates each date independently
✓ Interactive correction - Presents options with context
✓ Auto-trigger - Activates on Planning Hubs, timelines, calendars

Installation

Option 1: Download ZIP

1. Download date-validation-skill-v1.0.0.zip below
2. Extract to ~/.claude/skills/
3. Restart Claude Code

Option 2: Git Clone

cd ~/.claude/skills/
git clone https://github.com/JackReis/date-validation-skill.git date-validation

What Makes This Different

This skill was designed using Test-Driven Development for documentation:

• RED Phase: Ran 4 pressure scenarios WITHOUT the skill, documented exactly how agents fail
• GREEN Phase: Wrote skill addressing those specific failures
• Result: 10 documented rationalizations that agents use to skip validation, all prevented

Tested Scenarios

1. Day-of-week mismatch (trust anchor without verification)
2. Self-correction after first error (spot-fix, miss comprehensive validation)
3. Countdown math (manual calculation vs. systematic validation)
4. Sequential date trust (consistent ≠ correct)

See baseline-analysis.md and GREEN-TEST-RESULTS.md for full testing methodology.

License

MIT License

🤖 Generated with Claude Code