Skill: scan-conventions

Reads real code from the target codebase and extracts the actual conventions in use. Writes coding-conventions.md from evidence, not assumptions.

Step 1 — Locate the codebase

Look for:

• Primary language files (Java/JS/Python/TS — whatever the project uses)
• Main entry point or router file
• A utility/helper file with 5+ methods

If unclear, ask the user: "Where are the main source files? Any primary utility class I should read?"

Step 2 — Sample 3-5 real methods

Read actual methods. Look for:

Variable declarations:

• Declared at top of method or inline?
• Declared then assigned, or declaration + assignment combined?

SQL / DB patterns (if applicable):

• SQL assigned to a variable before passing to a query method?
• Parameterized queries? String concatenation? ORM?
• Specific quoting helpers (e.g. fmtCondition, fAddQuotes)?

Error handling:

• What does a failure return? "Error: ..." string? Exception? null?
• Specific error-check helpers (e.g. UFmt.containsError)?

Naming:

• camelCase, snake_case, PascalCase?
• Variable names include type prefix or drop it?

Control flow:

• Braces on every if/else, or omitted for single-statement bodies?
• Ternary operators used or avoided?
• Early returns or single-exit?

String comparison (Java/JS):

• var.equalsIgnoreCase("value") or "value".equalsIgnoreCase(var)?

Step 3 — Sample JS/frontend (if applicable)

• var vs let/const?
• Arrow functions vs function() {}?
• Template literals vs concatenation?
• DOM: getElementById vs querySelector vs $('#id')?
• Named params object before API call vs inline?

Step 4 — Identify INSERT strategy (if DB-heavy)

Grep for INSERT statements. Do any tables use auto-increment/IDENTITY? List them — they may need special handling (e.g. no explicit ID in INSERT).

Step 5 — Write coding-conventions.md

Write to coding-conventions.md in the project memory or root:

# Coding Conventions — [Project Name]
> Generated by /scan-conventions on [date].
> Based on [N] methods sampled from [files]. Review and correct anything that looks wrong.

## [Language] Conventions

### Variable Declarations
[finding]

### Error Handling
[finding]

### SQL / DB Pattern
[finding — or "N/A"]

### INSERT Strategy
[finding — list IDENTITY tables if found]

### Naming
[finding]

### Control Flow
[finding]

### String Comparison
[finding]

## JavaScript / Frontend (if applicable)

### Syntax
[finding]

### DOM Access
[finding]

### API Calls
[finding]

## ⚠️ Ambiguous — needs manual confirmation
[anything found with mixed usage — e.g. "Found both var and let — which is standard?"]

Step 6 — Report

Tell the user:

• Files sampled
• Key patterns confirmed
• Anything ambiguous that needs manual review

Ask: "Does this match what you know? Anything to correct before I treat this as authoritative?"

Notes

• This is a starting point, not a finished document
• Ambiguous patterns must be flagged — never assumed
• After the first real coding session, run /learn to add project-specific nuances
• Run again after a major refactor to catch convention drift