hidden-dependencies

Hidden Dependencies Discovery Command

Uncover hidden dependencies, implicit contracts, and non-obvious couplings that aren't immediately apparent from the code structure. These are the things that make changes risky and break unexpectedly.

Objective

Identify all the non-obvious ways different parts of the codebase depend on each other, including:

• Implicit data contracts
• Shared global state
• Ordering dependencies
• Temporal coupling
• Hidden assumptions
• Magic values and configurations

Step 1: Global State Analysis

Find all shared mutable state:

Types of Global State

• Global variables and singletons
• Static class fields
• Module-level state
• Environment variables that affect behavior
• Database connection pools
• Caches and memoization
• Feature flags

Output Format

## Global State Dependencies

### Global: [Name]
**Location**: `file_path:line_number`
**Type**: [Variable/Singleton/Cache/etc.]
**Mutability**: Read-only / Mutable

**What It Stores**: [Description of the data]

**Written By**:
- `file_path:line_number` - [Context]
- `file_path:line_number` - [Context]

**Read By**:
- `file_path:line_number` - [Usage context]
- `file_path:line_number` - [Usage context]
- [X more locations]

**Risk Assessment**:
- **Concurrency Issues**: [Thread-safety concerns]
- **Testing Difficulty**: [Hard to test because...]
- **Change Impact**: [What breaks if this changes]

**Hidden Assumptions**:
- [Assumption 1 about this state]
- [Assumption 2 about this state]

Step 2: Implicit Data Contracts

Identify places where code assumes specific data formats or structures:

Contract Types

• Expected JSON structures
• Database schema assumptions
• API response formats
• File formats
• String encoding assumptions
• Timezone assumptions

Output Format

## Implicit Data Contracts

### Contract: [Description]
**Location**: `file_path:line_number`

**Assumed Structure**:
```json
{
  "field1": "string",
  "nested": {
    "field2": 123
  }
}

Where It's Assumed:

• file_path:line_number - Expects field1 to exist
• file_path:line_number - Assumes nested.field2 is a number
• file_path:line_number - Relies on specific order

Not Validated:

• ✗ No null checks for nested object
• ✗ No type validation for field2
• ✗ No handling for missing fields

Breaking Changes Would Affect:

• [List of dependent code locations]

Recommendation:

• Add schema validation at: file_path:line_number
• Define explicit TypeScript interface / JSON Schema
• Add defensive null checks