ReddRadar
Agent skill
legacy-code-interpreter
Understand and document legacy code behavior through deep analysis and behavior characterization
Install this agent skill to your Project
npx add-skill https://github.com/a5c-ai/babysitter/tree/main/library/specializations/code-migration-modernization/skills/legacy-code-interpreter
SKILL.md
Legacy Code Interpreter Skill
Deep analysis and interpretation of legacy code to understand undocumented behavior, extract business logic, and characterize system functionality.
Purpose
Enable legacy code understanding for:
- Business logic extraction
- Undocumented feature discovery
- Behavior characterization
- Migration planning
- Knowledge preservation
Capabilities
1. Business Logic Extraction
- Parse conditional logic
- Extract calculation formulas
- Identify validation rules
- Document decision trees
2. Undocumented Feature Discovery
- Find hidden functionality
- Identify feature flags
- Discover Easter eggs
- Map admin features
3. Control Flow Analysis
- Trace execution paths
- Map state machines
- Identify loops and recursion
- Document entry points
4. Data Flow Tracking
- Trace data transformations
- Map input to output
- Identify side effects
- Document state changes
5. Side Effect Identification
- Find external calls
- Identify I/O operations
- Map database operations
- Document messaging
6. Behavior Characterization
- Create behavior summaries
- Generate pseudo-code
- Document edge cases
- Map error handling
Tool Integrations
| Tool | Purpose | Integration Method |
|---|---|---|
| Understand (SciTools) | Deep analysis | CLI / API |
| Lattix | Architecture analysis | CLI |
| CodeScene | Behavioral analysis | API |
| Sourcetrail | Code exploration | CLI |
| ast-grep | Pattern matching | MCP / CLI |
Output Schema
{
"analysisId": "string",
"timestamp": "ISO8601",
"interpretation": {
"businessLogic": [
{
"name": "string",
"location": "string",
"description": "string",
"pseudoCode": "string",
"inputs": [],
"outputs": [],
"sideEffects": []
}
],
"controlFlow": {
"entryPoints": [],
"stateMachines": [],
"criticalPaths": []
},
"dataFlow": {
"transformations": [],
"stateChanges": []
},
"undocumented": []
}
}
Integration with Migration Processes
- legacy-codebase-assessment: Primary interpretation tool
- migration-planning-roadmap: Knowledge source
Related Skills
static-code-analyzer: Structural analysisknowledge-extractor: Documentation mining
Related Agents
legacy-system-archaeologist: Uses for excavation
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