By name: googlesheet-blueprint-skill description: Generate complete Google Sheets formula documentation following APPSHEET_SYSTEM_BLUEPRINT.md templates for ARRAYFORMULA, VLOOKUP, QUERY, and calculated formulas. Use when documenting Google Sheets formulas, writing to docs/formulas/googlesheet_formulas.md, or when user mentions document formulas, ARRAYFORMULA, VLOOKUP, QUERY, or spreadsheet formulas. allowed-tools: - Read
Google Sheets Blueprint Skill
Generate complete documentation templates for Google Sheets formulas used in AppSheet projects.
When to Use This Skill
Automatic triggers (no user request needed):
- User is documenting Google Sheets formulas
- User is writing to
docs/formulas/googlesheet_formulas.md - User mentions: "document formulas", "ARRAYFORMULA", "VLOOKUP", "QUERY", "spreadsheet formula"
- User describes spreadsheet calculations or data transformations
- User is promoting experimental formulas to stable
Manual invocation:
/googlesheet-blueprint-skill
Example triggers:
- "Add documentation for this ARRAYFORMULA" → Auto-use formula template
- "Document the VLOOKUP in column F" → Auto-use formula template
- User writes to
googlesheet_formulas.md→ Auto-apply blueprint format
Template Overview
This skill provides complete documentation templates (see TEMPLATES.md):
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:
- version-management-skill - Orchestrates the workflow
- 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