Google Sheets Blueprint Skill

Available Templates:

• Column Formula Documentation - Formula Type, Cell Location, Range, Purpose, Dependencies, Behavior
• Common Formula Patterns - ARRAYFORMULA, VLOOKUP, QUERY with error handling
• Formula Dependencies - Cross-column and cross-sheet relationships

For complete templates with all fields, see TEMPLATES.md.

How to Use

Step 1: Identify Formula Type

Determine what needs documentation:

• ARRAYFORMULA? → Use auto-fill template
• VLOOKUP? → Use lookup template
• Calculated field? → Use calculation template
• QUERY/IMPORTRANGE? → Use data import template

Step 2: Read Template

Access the appropriate template from:

• TEMPLATES.md - All complete templates

Step 3: Generate Complete Documentation

Include ALL required fields:

• Formula Type: ARRAYFORMULA / VLOOKUP / IF / QUERY / IMPORTRANGE
• Cell Location: Starting cell (e.g., A2)
• Range Applied: Entire column or specific range
• Formula: Complete formula with proper indentation
• Purpose: What this formula does
• Dependencies: Other columns/sheets it references
• Behavior: How it updates, edge cases, performance notes
• Example Output: Input → Output examples

Step 4: Verify Completeness

Check against requirements:

• All formulas documented with complete configuration
• Dependencies clearly listed
• Behavior and notes included
• Example outputs provided

Quick Template Preview

ARRAYFORMULA Documentation (Minimal Example)

Column E: Second Installment Date

Purpose: Auto-calculate second installment due date (1 month after start date)

Formula Location: Batch Data!E:E Type: ARRAYFORMULA Trigger: Populates when Batch Starting Date (Column C) is filled

Formula:

=ARRAYFORMULA(
    IF(
        ROW(C:C)=1,
        "Second Installment Date",
        IF(
            ISBLANK(C:C),
            "",
            EDATE(C:C, 1)
        )
    )
)

**How It Works:**
1. Header Row: If row number is 1, displays "Second Installment Date"
2. Blank Check: If Batch Starting Date (Column C) is blank, returns empty string
3. Date Calculation: Uses EDATE to add 1 month to Batch Starting Date

**Example Output:**
- Batch Starting Date: 2024-06-15
- Second Installment Date: 2024-07-15

**Dependencies:**
- Requires: Column C (Batch Starting Date)
- Updates: Automatically when Batch Starting Date changes

VLOOKUP Documentation (Minimal Example)

Column F: Batch Starting Date

Purpose: Inherit Batch Starting Date from Batch Data table

Formula Location: Student Data!F:F Type: ARRAYFORMULA with VLOOKUP Trigger: Populates when Batch (Column B) is selected

Formula:

=ARRAYFORMULA(
    IF(
        ROW(B:B)=1,
        "Batch Starting Date",
        IF(
            ISBLANK(B:B),
            "",
            VLOOKUP(B:B, 'Batch Data'!B:C, 2, FALSE)
        )
    )
)

**Dependencies:**
- Requires: Column B (Batch) to be filled
- Requires: Batch Data table with matching batch names
- Updates: Automatically when Batch Data is updated

See TEMPLATES.md for complete templates with all fields.

Common Formula Patterns

Pattern 1: ARRAYFORMULA for Auto-Fill

=ARRAYFORMULA(IF(B2:B="","",FORMULA_HERE))

Use Case: Apply formula to entire column, skip blank rows

Pattern 2: VLOOKUP with Error Handling

=IFERROR(VLOOKUP(A2, 'OtherSheet'!A:B, 2, FALSE), "Not Found")

Use Case: Safe lookup with fallback value

Pattern 3: Conditional Calculation

=ARRAYFORMULA(IF(ROW(A:A)=1,"Header",IF(ISBLANK(A:A),"",CALCULATION)))

Use Case: Auto-fill with header row and blank handling

Completeness Requirements

Formula documentation MUST include:

• ✅ Formula Type (ARRAYFORMULA, VLOOKUP, etc.)
• ✅ Cell Location and Range Applied
• ✅ Complete Formula with proper indentation
• ✅ Purpose (what it does)
• ✅ Dependencies (other columns/sheets)
• ✅ Behavior (how it updates, edge cases)
• ✅ Example Output (input → output)
• ✅ Notes (special considerations)

Version Management

For the complete Experimental→Stable promotion workflow, use /version-management-skill.

Quick Reference: The 2-Version System

Formula documentation files follow a 2-version discipline:

googlesheet_formulas.md
├── EXPERIMENTAL V[X]  (new formulas being tested)
└── STABLE SYSTEM V[X-1]  (current production)

Key Concepts:

• V3 = V2 + new formulas (cumulative, not replacement)
• Old versions are archived to backups/[date]-v[X]-stable/
• STABLE documentation must be self-contained

Version Management Triggers

Starting new features:

• "Let's build a new feature" → Creates EXPERIMENTAL V[X] section
• "Let's add a new formula" → Same as above

Promoting to stable:

• "Mark the system as stable" → Promotes EXPERIMENTAL → STABLE
• "Promote to stable" → Same as above

For Complete Workflow

Use /version-management-skill which handles:

• Creating EXPERIMENTAL sections for new formulas
• Archiving current STABLE before promotion
• Integrating Experimental into STABLE
• Updating CHANGELOG.md
• Verifying completeness

Coordination With Other Skills

When promoting to stable:

1. version-management-skill - Orchestrates the workflow
2. googlesheet-blueprint-skill (this skill) - Ensures formula template compliance

Scope and Limitations

In Scope

✅ Google Sheets formula documentation templates ✅ ARRAYFORMULA patterns and best practices ✅ VLOOKUP/QUERY documentation format ✅ Formula dependency tracking ✅ Cross-sheet formula documentation

Out of Scope

❌ Google Sheets formula syntax help (use built-in docs or web search) ❌ Formula debugging/troubleshooting (use Google Sheets help) ❌ Spreadsheet design/architecture (use appsheet-blueprint-skill for table structure)

Important Notes

AUTOMATIC INVOCATION: When documenting any Google Sheets formula, you MUST automatically use blueprint templates to ensure completeness. This ensures ALL required fields are included.

Always use complete templates: Don't omit fields. Every formula needs: Formula Type, Cell Location, Range, Formula, Purpose, Dependencies, Behavior, Example Output, Notes.

Templates are in TEMPLATES.md: Use TEMPLATES.md as the source of truth for all documentation format templates.

Detailed Templates and Examples

For comprehensive templates and real-world examples, see:

• TEMPLATES.md - Complete templates for all formula types
• EXAMPLES.md - Real examples from production documentation

Version: 1.0 Last Updated: 2026-01-21 Source: googlesheet-blueprint-skill/SKILL.md